ICEA S-I 08-720-2004
STANDARD FOR EXTRUDED INSULATION P O M R CABLES RATED ABOVE 46 THROUGH 345 KV
Publication K E A S-108-720-2004 July 15,2004
0 2004 by
INSULATED CABLE ENGINEERS ASSOCIATION, Inc.
ICEA S-I 08-720-2004
STANDARD FOR
EXTRUDED INSULATION POWER CABLES RATED ABOVE 46 THROUGH 345 KV
Standard ICEA S-108-720-2004 Published By INSULATED CABLE ENGINEERS ASSOCIATION, Inc. Post Office Box 1568 Carrollton, Georgia 30112, U.S.A.
Approved by Insulated Cable Engineers Association, Inc.: June 7,2004 Accepted by AEIC: Cable Engineering Committee: February 9,2004 Approved by ANSI:
0 Copyright 2004 by the Insulated Cable Engineers Association, Inc. All rights including translation into other languages, reserved under the Universal Copyright Convention, the Berne Convention for the Protection of Literary and Artistic Works, and the international and Pan American Copyright Conventions.
DATE: 7/15/04
KEA S-I 08-720-2004
FOREWORD
This Standards Publication for Extruded Insulation Power Cables Rated above 46 to 345 kV (ICEA S108-720) was developed by the Insulated Cable Engineers Association Inc. (ICEA). ICEA standards are adopted in the public interest and are designed to eliminate misunderstandings between the manufacturer and the purchaser and to assist the purchaser in selecting and obtaining the proper product for his particular need. Existence of an ICEA standard does not in any respect preclude the manufacture or use of products not conforming to the standard. The user of this Standards Publication is cautioned to observe any health or safety regulations and rules relative to the manufacture and use of cable made in conformity with this Standard. Requests for interpretation of this Standard must be submitted in writing to the Insulated Cable Engineers Association, Inc., P. O. Box 1568, Carrollton, Georgia 30112. An official written interpretation will be provided. Suggestions for improvements gained in the use of this Standard will be welcomed by the Association. The ICEA expresses thanks to the Association of Edison Illuminating Companies, Cable Engineering Committee for providing the basis for some of the matenal included herein through their participation in the Utility Power Cable Standards Technical Advisory Committee (UPCSTAC), and to the Institute of Electrical and Electronics Engineers, Insulated Conductors Committee, Subcommittee A, Discussion Group A-I 4 for providing user input to this Standard. The members of the ICEA working group contributing to the writing of this Standard consisted of the following:
f. Kuchta, Chairman E. Bartolucci J. Cancelosi L. Hiivala R. Thrash
R. Bnstoi P. Cinquemani A. Pack E.Walcott
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S.Campbell B. Fleming
B.Temple N.Ware
DATE: 7115/04
ICEA S-108-720-2004
TABLE OF CONTENTS Part 1 GENERAL .............................................................................................................................................. 1.1 SCOPE.................................................................................................................................................... 1.2 GENERAL INFORMATION................................................................................................................... 1.3 INFORMATIONTO BE SUPPLIED BY PURCHASER........................................................................ 1.3.1 Characteristics of Systems on which Cable is to be Used ...................................................... 1.3.2 Description of Installation.......................................................................................................... 1.3.3 Quantities and Description of Cable......................................................................................... 1.4 INFORMATION TO BE SUPPLIED BY MANUFACTURER............................................................... 1.5 DEFINITIONSAND SYMBOLS.............................................................................................................
i 1 1 1 1 2 2 2 2
Part 2 CONDUCTOR ........................................................................................................................................ 6 2.0 GENERAL .............................................................................................................................................. 6 2.1 PHYSICAL AND ELECTRICAL PROPERTIES...................................................................................6 2.1.1 Copper Conductors................................................................................................................... 6 2.1.2 Aluminum Conductors .............................................................................................................. 6 2.1.3 Special Conductors................................................................................................................... 6 2.1.3.1 Segmental Conductors................................................................................................ 7 2.2 OPTIONAL SEALANT FOR STRANDED CONDUCTORS ................................................................ 7 2.3 CONDUCTOR SIZE UNITS................................................................................................................... 7 2.4 CONDUCTOR DC RESISTANCE......................................................................................................... 7 Direct Measurement of dc Resistance Per Unit Length........................................................... 7 2.4.1 Calculation of dc Resistance Per Unit Length.......................................................................... 8 2.4.2 2.5 CONDUCTOR DIAMETER.................................................................................................................... 8 CONDUCTOR SHIELD........................................................................................................................ MATERIAL ........................................................................................................................................... EXTRUDEDSHIELD THICKNESS..................................................................................................... PROTRUSIONSAND IRREGULARITIES.......................................................................................... VOIDS ................................................................................................................................................... PHYSICAL REQUIREMENTS............................................................................................................. ELECTRICALREQUIREMENTS ........................................................................................................ Extruded Semiconducting Material......................................................................................... 3.6.1 3.6.2 Extruded Nonconducting Material (For EPR Insulation Only) ............................................... 3.6.3 Semiconducting Tape ............................................................................................................. 3.7 WAFER BOIL TEST.............................................................................................................................
Part 3 3.1 3.2 3.3 3.4 3.5 3.6
14
14 14 14 14 15 15 15 15 15 15
Part 4 INSULATION........................................................................................................................................ 16 4.1 MATERIAL ........................................................................................................................................... 16 4.2 INSULATION THICKNESS ................................................................................................................. 16 Selection of Proper Thicknesc ................................................................................................ 17 4.2.1 4.2.2 Insulation Eccentricity ............................................................................................................. 18 4.3 INSULATION REQUIREMENTS......................................................................................................... 18 4.3.1 Physical and Aging Requirements ......................................................................................... 18 Electrical Test Requirements.................................................................................................. 19 4.3.2 Partial-Dischargefor Discharge-Free Designs only ................................................. 19 4.3.2.1 4.3.2.2 Voltage Tests............................................................................................................. 20 Insulation Resistance Test ........................................................................................ 20 4.3.2.3 Dielectric Constant and Dissipation Factor............................................................... 21 4.3.2.4 Discharge (Corona) Resistance fro Discharge-Resistant EPR Designs only ......... 21 4.3.2.5
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4.3.3 Voids. Ambers. Gels. Agglomerates and Contaminants as Applicable ................................ 21 4.3.3.1 Crosslinked Polyethylene Insulation (XLPE) ............................................................ 21 4.3.3.2 Ethylene Propylene Rubber (EPR)........................................................................... 21 4.3.4 Shnnkback - Crosslinked PolyethyieneInsulation(XLPE) Only ........................................... 22 Part 5 5.1 5.2 5.3 5.4 5.5
EXTRUDEDINSULATION SHIELD.................................................................................................... 23 MATERIAL ........................................................................................................................................... 23 THICKNESS REQUIREMENTS.......................................................................................................... 23 PROTRUSIONSAND IRREGULARITIES.......................................................................................... 23 SEMICONDUCTINGTAPE ................................................................................................................. 23 INSULATIONSHIELD REQUIREMENTS .......................................................................................... 23 .. 5.5.1 Removability............................................................................................................................ 23 5.5.2 Voids........................................................................................................................................ 24 5.5.3 Physical Requirements........................................................................................................... 24 5.5.4 Electrical Requirements.......................................................................................................... 24 5.5.5 Wafer Boil Test........................................................................................................................ 24
Part 6 METALLIC SHIELDING....................................................................................................................... 25 6.1 GENERAL ............................................................................................................................................ 25 6.2 SHIELDS .............................................................................................................................................. 25 6.2.1 Helically Applied Tape Shield ................................................................................................. 25 6.2.2 LongitudinallyApplied And Overlapped Corrugated Tape Shield ......................................... 25 6.2.3 Wire Shield .............................................................................................................................. 25 6.2.4 Flat Strap Shield...................................................................................................................... 26 6.3 SHEATHS............................................................................................................................................. 26 6.3.1 Lead Sheath............................................................................................................................ 26 6.3.2 Smooth Aluminum Sheath...................................................................................................... 26 6.3.3 Continuously Corrugated Sheath ........................................................................................... 26 6.4 RADIAL MOISTURE BARRIER.......................................................................................................... 27 6.5 OPTIONAL LONGITUDINAL WATER BLOCKiNG COMPONENTS............................................... 27 Part 7 JACKET ................................................................................................................................................ 7.1 MATERIAL ........................................................................................................................................... 7.1 .1 Polyethylene, Black................................................................................................................. 7.1.2 Polyvinyl Chloride.................................................................................................................... 7.2 JACKET APPLICATION AND THICKNESS...................................................................................... 7.2.1 Thickness of Jacket for Tape and Wire Shields..................................................................... 7.2.2 Thickness of Jacket for Sheaths............................................................................................. 7.3 OPTIONAL SEMICONDUCTINGCOATING...................................................................................... 7.4 JACKET IRREGULARITY INSPECTION........................................................................................... 7.4.1 Jackets without Optional Semiconducting Coating................................................................ 7.4.2 Jackets with Optional SemiconductingCoating.....................................................................
28 28 28 29
Part 8 CABLE IDENTIFICATION................................................................................................................... 8.1 CABLE IDENTIFICATION................................................................................................................... 8.1.I Optional Center Strand Identification ..................................................................................... 8.1.2 Optional Sequential Length Marking......................................................................................
33 33 33 33
Part 9 9.1 9.2 9.3
30 30 30 30 30 30 30
PRODUCTIONTESTS......................................................................................................................... 34 TESTING .............................................................................................................................................. 34 SAMPLING FREQUENCY................................................................................................................... 34 CONDUCTOR TEST METHODS ........................................................................................................ 34 9.3.1 Method for DC ResistanceDetermination ............................................................................. 34
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ICEA S-108-720-2004
9.4
9.5
9.6 9.7
9.8
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9.3.2 Cross-sectional Area Determination...................................................................................... 34 9.3.3 Diameter Detemiination.......................................................................................................... 34 TEST SAMPLES AND SPECIMENS FOR PHYSICAL AND AGING TESTS .................................. 34 9.4.1 General.................................................................................................................................... 34 9.4.2 Measurement of Thickness .................................................................................................... 34 9.4.2.1 Micrometer Measurements....................................................................................... 35 Optical Measuring Device Measurements................................................................ 35 9.4.2.2 Number of Test Specimens.................................................................................................... 35 9.4.3 Size of Specimens.................................................................................................................. 9.4.4 35 Preparationof Specimens of Insulation and Jacket............................................................... 36 9.4.5 9.4.6 Specimenfor Aging Test ........................................................................................................ 36 9.4.7 Calculation of Area of Test Specimens .................................................................................. 36 36 9.4.8 Unaged Test Procedures........................................................................................................ 36 9.4.8.1 Test Temperature...................................................................................................... Type of Testing Machine........................................................................................... 36 9.4.8.2 Tensile Strength Test ................................................................................................ 36 9.4.8.3 9.4.8.4 Elongation Test.......................................................................................................... 37 9.4.9 Aging Tests ............................................................................................................................. 37 9.4.9.1 Aging Test Specimens .............................................................................................. 37 9.4.9.2 Air Oven Test............................................................................................................. 37 Oil ImmersionTest for Polyvinyl Chloride Jacket ..................................................... 37 9.4.9.3 9.4.10 Hot Creep Test........................................................................................................................ 38 9.4.1 1 Solvent Extraction................................................................................................................... 38 9.4.12 Wafer Boil Test for Conductor and Insulation Shields ........................................................... 38 9.4.12.1 InsulationShield Hot Creep Properties .................................................................... 38 9.4.13 Amber, Agglomerate, Gel, Contaminant, Protrusion, Irregulantyand Void Test .................. 38 9.4.1 3.1 Sample Preparation................................................................................................... 38 9.4.13.2 Examination............................................................................................................... 38 9.4.1 3.3 Resamplingfor Amber, Agglomerate, Gel, Contaminant, Protrusion, Irregularity and Void Test ....................................................................... 39 9.4.1 3.4 Protrusionand Irregularity Measurement Procedure............................................... 39 9.4.14 Physical Tests for Semiconducting Material Intendedfor Extrusion..................................... 40 9.4.1 4.1 Test Sample............................................................................................................... 40 9.4.14.2 Test Specimens......................................................................................................... 40 9.4.14.3 Elongation.................................................................................................................. 40 9.4.15 Retests for Physical and Aging Propertiesand Thickness.................................................... 40 DIMENSIONAL MEASUREMENTS OF THE METALLIC SHIELD................................................... 40 9.5.1 Tape Shield ............................................................................................................................. 40 9.5.2 Wire Shield .............................................................................................................................. 40 9.5.3 Sheath ..................................................................................................................................... 41 9.5.4 Flat Straps ............................................................................................................................... 41 DIAMETER MEASUREMENT OF INSULATION AND INSULATION SHIELD ............................... 41 TESTS FOR JACKETS ....................................................................................................................... 41 9.7.1 Heat Shock.............................................................................................................................. 41 Preparationof Test Specimen .................................................................................. 41 9.7.1 .I Winding of the Test Specimen on Mandrels............................................................. 41 9.7.1.2 Heating and Examination.......................................................................................... 42 9.7.1.3 9.7.2 Heat Distortion......................................................................................................................... 42 9.7.3 Cold Elongation....................................................................................................................... 42 9.7.3.1 Test Temperature...................................................................................................... 42 9.7.3.2 Type of Testing Machine........................................................................................... 42 9.7.3.3 ElongationTest.......................................................................................................... 42 VOLUME RESISTIVITY....................................................................................................................... 43
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ICEA 8-108-720-2004
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9.8.1 Conductor Shield..................................................................................................................... 43 9.8.2 Insulation Shield and Semiconducting Extruded Jacket Coating .......................................... 43 9.8.3 Test Equipment ....................................................................................................................... 43 9.8.4 Test Procedure........................................................................................................................ 44 SHRINKBACK TEST PROCEDURE............................................................................................. 44 9.9 9.9.1 Sample Preparation ................................................................................................................ 44 9.9.2 Test Procedure........................................................................................................................ 44 9.9.3 Pass/Fail Criteria and Procedure............................................................................................ 44 9-10 RETESTS ON SAMPLES............................................................................................................... 44 9.11 AC VOLTAGE TEST ...................................................................................................................... 45 9.1 1.1 General.................................................................................................................................... 45 9.1 1.2 AC Voltage Test ...................................................................................................................... 45 9.12 PARTIAL-DISCHARGE TEST PROCEDURE .............................................................................. 45 9.13 METHOD FOR DETERMINING DIELECTRIC CONSTANT AND DIELECTRIC STRENGTH OF EXTRUDED NONCONDUCTING POLYMERIC STRESS CONTROL LAYERS................................................................................ 45 9.14 WATER CONTENT......................................................................................................................... 45 9.14.1 Water Under the Jacket .......................................................................................................... 46 9.14.2 Water in the Conductor ........................................................................................................... 46 9.14.3 Water Expulsion Procedure.................................................................................................... 46 9.14.4 Presence of Water Test .......................................................................................................... 46 47 9.15 PRODUCTION TEST SAMPLING PLANS.................................................................................... QUALIFICATION TESTS ............................................................................................................... 50 GENERAL ....................................................................................................................................... 50 10.1 CABLE QUALIFICATION TESTS ................................................................................................. 50 50 10.1.1 Cable Design Qualification ..................................................................................................... 10.1.2 CaMe Bending Procedure....................................................................................................... 53 10.1.2.1 Bending Diameter...................................................................................................... 53 1O.1.3 Thermal Cycling Procedure.................................................................................................... 53 10.1.3.1 Thermal Cycles..........................................................................................................53 54 Voltage During Themal Cycles ................................................................................ 10.1.3.2 10.1.4 Hot Impulse Test Procedure................................................................................................... 54 10.1.5 AC Voltage Withstand Test Procedure ................................................................................... 10.1.6 Partial Discharge Test Procedure (For Discharge-Free Designs Only) ................................ 54 10.1.7 Measurement of Dissipation Factor........................................................................................54 10.1.8 Dissection and Analysis of Test Specimens .......................................................................... 54 55 10.2 JACKET MATERIAL QUALIFICATION TESTS ........................................................................... 10.2.1 Polyethylene Jackets .............................................................................................................. 55 10.2.1.1 Environmental Stress Cracking Test ........................................................................ 55 10.2.1.1.1 Testspecimen....................................................................................................55 10.2.1.1.2 Test Procedure ................................................................................................... 55 10.2.1.2 Absorption Coefficient Test ....................................................................................... 55 10.2.2 Semiconducting Extnided Jacket Coatings ........................................................................... 55 10.2.2.1 Brittleness Temperature............................................................................................ 55 10.2.3 Polyvinyl Chloride.................................................................................................................... 55 10.2.3.1 Sunlight Resistance................................................................................................... 55 10.2.3.1.1 Test Samples...................................................................................................... 55 10.2.3.1.2 Test Procedure ................................................................................................... 55 10.3 OTHER QUALIFICATION TESTS ................................................................................................. 56 10.3.1 Insulation Resistance.............................................................................................................. 56 10.3.2 Accelerated Water Absorption Tests...................................................................................... 56 .. 10.3.3 Resistance Stability Test......................................................................................................... 56
Part IO 10.0
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ICEA S-108-720-2004
DATE: 7/15/04
10.3.4 BrittlenessTemperature for SemiconductingShields............................................................ 57 10.3.5 Discharge Resistance Test for Discharge-ResistantEPR Designs only .............................. 57 10.3.5.1 Test Specimens......................................................................................................... 57 10.3.5.2 Test Environment ...................................................................................................... 57 10.3.5.3 Test Electrodes..........................................................................................................57 Part 11 APPENDICES ................................................................................................................................. 58 NEMA, ICEA, IEEE, ASTM AND ANSI STANDARDS (Normative) ..................... 58 APPENDIX A Al NEMA PUBLICATIONS.......................................................................................................... 58 A2 ICEA PUBLICATIONS ............................................................................................................ 58 IEEE AND ANSI STANDARDS.............................................................................................. 58 A3 A4 ASTM STANDARDS............................................................................................................... 58 EMERGENCY OVERLOADS (Normative) ............................................................. 61 APPENDIX B PROCEDUREFOR DETERMININGTHICKNESS REQUIREMENTS APPENDIX C OF THE INSULATIONSHIELD, LEAD SHEATH AND JACKET (Normative)....63 CABLE COMPONENT FUNCTION(Informative).................................................. 65 APPENDIX D D1 CONDUCTOR......................................................................................................................... 65 D1.l Function..................................................................................................................... 65 D1.2 Material...................................................................................................................... 65 02 CONDUCTOR SHIELD .......................................................................................................... 65 D2.1 Function..................................................................................................................... 65 D2.1.1 Nonconducting.... ............................................................................................... 65 D2.1.2 Semiconducting.................................................................................................. 65 D2.2 Voltage Stress ........................................................................................................... 65 O3 INSULATION........................................................................................................................... 66 04 INSULATIONSHIELD ............................................................................................................ 66 D4.1 SemiconductingShield.............................................................................................. 67 D4.2 Metallic Shield............................................................................................................ 67 D5 JACKET................................................................................................................................... 67 APPENDIX E HANDLING AND INSTALLATION PARAMETERS (Informative) ........................ 69 El INSTALLATIONTEMPERATURES.................................................................... ..................69 E2 RECOMMENDED MINIMUM BENDING RADIUS ................................................................ 69 E3 DRUM DIAMETERS OF REELS............................................................................................ 69 E4 MAXIMUM TENSION AND SIDEWALL BEARING PRESSURES....................................... 69 E5 ELECTRICALTESTS AFTER INSTALLATION .................................................................... 70 E5.1 Insulation.................................................................................................................... 70 E5.2 Jacket......................................................................................................................... 70 APPENDIX F TRADITIONAL INSULATIONWALL THICKNESS (Informative)......................... 71 APPENDIX G ADDiTiONAL SHIELD WIRE AND CONDUCTOR INFORMATION (Informative)72 ETHYLENEALKENE COPOLYMER (EAM) (Informative)................................... APPENDIX H 75 APPENDIX I SPECIFICATION FOR ALLOY LEAD SHEATHS (Informative)........................... 76 Il PURPOSE............................................................................................................................... 76 12 MATERIAL ..............................................................................................................................76 13 REQUIREMENTS................................................................................................................... 76
LIST OF TABLES Table 2-1 Table 2-2 Table 2-2 (Metric)
Weight Increment Factors ........................................................................................... Nominal Direct Current Resistance in Ohms Per 1000 Feet at 25 OC of Concentric Lay Stranded and Segmental Conductor ......................................... Nominal Direct Current Resistance in Milliohms Per Meter at 25 OC of Concentric Lay Stranded and Segmental Conductor .......................................
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ICEA S-108-720-2004 Table 2-3 Table 2-3 (Metric) Table 2 4 Table 2 3 Table 3-1 Table 4-1 Table 4-2 Table 4-3 Table 4-4 Table 4 5 Table 4-6 Table 4-7 Table 4-8 Table 5-1 Table 6-1 Table 7-1 Table 7-2 Table 7-3 Table 7-4 Table 7 6 Table 9-1 Table 9-2 Table 9-3 Table 9 4 Table 9 5 Table 10-1 Table 10-2 Table D-I Table E-I Table F-I Table G-1 Table 6-2 Table 6-3 Table 1-1
DATE: 7/15/04 Nominal Diameters for Round Copper and Aluminum Conductors.................... i1 Nominal Diametersfor Round Copper and Aluminum Conductors.................... 12 Nominal Diameters for Segmental Copper and Aluminum Conductors............. 13 Factors for Determining Nominal Resistance of Stranded Conductors Per 1000 Feet at 25 OC................................................................................................ 13 Extruded Conductor Shield Thickness.................................................................... 14 Conductor MaximumTemperatures ........................................................................ 16 Conductor Sizes, Maximum Insulation Eccentricity, Insulation Maximum Stress and Test Voltages ........................................................................................... 18 Insulation Physical Requirements............................................................................ 19 Pattial-Discharge Requirements............................................................................... 19 Test Voltages for Partial-DischargeMeasurements .............................................. 20 Impulse Values............................................................................................................ 20 Dielectric Constant and Dissipation Factor ............................................................ 21 Shrinkback Test Requirements................................................................................ 22 Insulation Shield Thickness...................................................................................... 23 Lead Sheath Thickness.............................................................................................. 26 Polyethylene, Black .................................................................................................... 28 Polyvinyl Chloride....................................................................................................... 29 Semiconducting Extruded Coating.......................................................................... 31 Jacket Thickness and Test Voltage for Tape or Wire Shield Cables ................... 31 Jacket Thickness and Test Voltage for All Sheath Cables ................................... 32 Test Specimens for Physical and Aging Tests ....................................................... 35 Bending Requirementsfor Heat Shock Test .......................................................... 42 Summary of ProductionTests and Sampling Frequency Requirements ...........47 Plan E ........................................................................................................................... 49 Plan F............................................................................................................................ 49 Generic Grouping of Cable Components................................................................ 51 Accelerated Water Absorption Properties .............................................................. 56 Jacket Functions ........................................................................................................ 67 Recommended Minimum Bending Radius ............................................................. 69 Traditional Insulation Thickness from AEIC CS7-93, Test Voltages and Conductor Sues .................................................................................................. 71 Solid Copper Shield Wires ........................................................................................ 72 Concentric Stranded Class B Aluminum and Copper Conductors..................... 73 Concentric Stranded Class C and D Aluminum and Copper Conductors..........74 Chemical Requirementsfor Alloy Lead Sheaths ...................................................76
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DATE: 7/15/04
ICEA S-108-720-2004
Part 1 GENERAL
1.ISCOPE This standard applies to materials, constructions, and testing of crosslinked polyethylene (XLPE) and ethylene propylene rubber (EPR) insulated single conductor shielded power cables rated above 46 to 345 kV used for the transmission of electrical energy.
1.2 GENERAL INFORMATION This publication is arranged to allow for selection of individual components (such as conductors, insulation, semiconducting shields, metallic shields, jackets, etc.) as required for specific installation and service conditions. Parts 2 to 7 cover the major components of cables: Part 2 - Conductor Part 3 - Conductor Shield Part 4 - Insulation Part 5 - Extruded Insulation Shield Part 6 - Metallic Shielding Part 7 - Jacket Each of these parts designates the materials, material characteristics, dimensions, and tests applicable to the particular component. Part 8 covers identification of cables. Part 9 covers production test procedures applicable to cable component materials and to completed cables. Part 1O covers qualification test procedures. Part 11 contains appendices of pertinent information. Units in these standards are generally expressed in the Imperial system. For information only, their approximate metric equivalents are included.
1.3 INFORMATION TO BE SUPPLIED BY PURCHASER When requesting proposals from cable manufacturers, the prospective purchaser should describe the cable desired by reference to pertinent provisions of these standards. To help avoid misunderstandings and possible misapplication of the cable, the purchaser should also furnish the following information:
1.3.1
Characteristics of Systems on which Cable is to be Used
a. b. c. d.
Desired ampacity for normal and emergency operation. Frequency. Nominal phase to phase operating voltage. Maximum phase to phase operating voltage. d. Basic Impulse Voltage. e. Symmetrical and asymmetrical fault current and duration for conductor and metallic shieldlsheath. f. Daily load factor.
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ICEA S-108-720-2004 1.3.2
DATE 7/15/04
Description of Installation
a. Installation method and geometry, for example: 1. In underground ducts. 2. Direct buried in ground. 3. In air and whether the effects of wind andlor solar radiation should be considered. 4. In tunnel and whether there are special fire retardant features. 5. Descriptions other than the foregoing. b. Installation conditions. 1. Ambient air temperature andor ambient ground temperature at burial depth. 2. Minimum temperature at which cable will be installed. 3. Number of loaded cables in direct buried cable chase, duct bank or conduit system. If in cable chase, describe cable spacing and burial depth. If in conduit, describe size (id and od)type of conduit (metallic or nonmetallic), number of occupied and unoccupied conduits, whether endosed or exposed, spacing between conduits and burial depth of conduits. 4. Method of bonding and grounding of metallic shieldsheath. 5. Wet or dry location. 6. Thermal resistivity (rho) of coil, concrete andlor thermal backfill.
1.3.3
Quantities and Description of Cable
Total cable length, including any special test lengths, and specific shipping lengths if required. Nominal phase to phase voltage. Type of conductor - copper or aluminum, filled or unfilled strand. Size of conductors in circular mils. If conditions require other than standard stranding, a complete description should be given. e. Type of insulation. f. Type of metallic shieldsheath. g. Type of jacket. h. Maximum allowable overall diameter, iflimited by conduit inside diameter or other considerations. i. Method of cable identification. a. b. c. d.
1.4INFORMATION TO BE SUPPLIED BY MANUFACTURER When submitting proposals to the prospective purchaser, cable manufacturers shall describe the cable proposed to this standard. To help avoid misunderstandings, the manufacturer shall furnish at least the following information: a. Nominal insulation thickness. b. A complete description of the cable including dimensions and material description of each layer. This infonation maybe in the form of a drawing. C. Nominal phase to phase voltage. d. Normal conductor maximum operation temperature the cable was designed to meet. e. Emergency conductor maximum operation temperature the cable was designed to meet. f. Fault capacity as defined by customer parameters. 9. The voltage stress at the conductor shield/insulation interface (maximum stress) and at the insulationíinsulationshield interface (minimum stress). h. Maximum allowable pulling tension and sidewall bearing pressure. I. Dielectric constant.
IJDEFINITIONS AND SYMBOLS Active Length:
Length of cable covered by insulation shield and metallic shield.
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ICEA S-108-720-2004
DATE: 7/15/04
A discernible area of compound constituents in ethylene propylene based insulation which is generally opaque and can be broken apart.
Agglomerate: Amber:
A localized area in crosslinked polyethylene insulation which is dissimilar in color (ranging from bright yellow to dark red) from the surrounding insulation, which passes light and is not always readily removable from the insulation matrix. This does not include douds, swirls or flow patterns which are normally associatedwith the extnrsion process.
AWG:
American Wire Gauge
BIL:
Basic Impulse insulation Level.
Cable Core:
The portion of a cable which includes the conductor, the conductor shield, the insulation and the extruded insulation shield.
Cable Core Extruder Run:
A continuous run of cable core with one conductor size, one conductor shield compound, one insulation compound and thickness, and one insulation shield compound.
Certified Test Report:
A report containing the results of producuon tests or qualification tests which dedares that the cable shipped to a customer meets the applicable requirements of this standard.
Contaminant:
Any solid or liquid material which is not an intended ingredient.
Dielectric Constant:
The ratio of the capacitance of a given configuration of electrodes with the material as a dielectric to the capacitance of the same electrode configuration with a vacuum (or air for most practical purposes) as the dielectric.
Discharge-Free Cable Design:
A cable designed to eliminate electrical discharge in the insulation system at normal operating voltage.
DischargeResistant Cable Design:
A cable design capable of withstanding electrical discharge in the insulation system at normal operating voltage.
Dissipation Factor:
The cotangent of the dielectric phase angle of a dielectric material or the tangent of the dielectric loss angle. It is often called tan 6.
Dry Location:
A location not normally subject to dampness or wetness.
EPR Insulating Compound:
A mixture of ethylene propylene base resin and selected ingredients.
Gel:
A discernible region of cornpound constituents in ethylene propylene based insulation which is gelatinous, not readily removable from the insulation, and generally translucent.
High Dielectric Constant Compound:
An extruded compound used for the conductor shield which has a dielectric constant typically between 8 and 200.
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DATE: 7115/04
ICEA S-108-720-2004 Jacket Extruder Run:
A cable with a jacket which was applied in one continuous run with one jacket compound and one jacket thickness.
kcmil:
Thousands of circular mils.
Lot (Cable):
The quantity of cabie requiring one test.
Lot (Material):
A quantity of material used in cable conshction which is produced at the same location under the same manufacturing conditions during the same time period.
Master Length:
A continuous length of cable collected on a reel at the end of an extrusion line.
Maximum Conductor Temperatures: Normal Operating:
The highest conductor temperature permissible for any part of the cable under normal operating current load.
Emergency Overload:
The highest conductor temperature permissible for any part of the cable during emergency overload of specified time, magnitude, and frequency of application.
Short Circuit:
The highest conductor temperature permissible for any part of the cable during a circuit fault of specified time and magnitude.
Nominal Value:
The value by which a quantity is designated and often used in tables (taking into account specified tolerances).
Partial Discharge Level:
The maximumcontinuous or repetitious apparent charge transfer, measured in picocoulombs, occumng at the test voltage.
pC:
picocoulombs
Production Tests:
Tests defined in Part 9 of this standard with specific test frequency.
Qualification Tests:
Tests defined in Part 1O of this standard with specific test frequency.
Rated Voltage:
Nominal phase to phase operating voltage.
Room Temperature (RT):
25 OC15
Shipping Length:
A completed length of cable which has passed all test requirements. It may or may not be cut into shorter lengths before it is supplied to the end use customer.
Shipping Reel:
A completed reel of cable shipped to the end use customer.
Translucent:
A localized area in crosslinked polyethylene insulation dissimilar to the surrounding insulation which passes light and is not readily removable from the insulation matrix. There are no requirements for translucents in this standard.
v:
Nominal phase-to-phase operating voltage (Rated Voltage).
OCair temperature.
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DATE: 7/15/04
ICEA S-108-720-2004
V,:
Nominal phase-to-gmund operating voltage
V,:
Phase-to-ground test voltage
Vented Water Tree:
A water tree which originates at the conductor shield or insulation shield.
Void:
Any cavity in a compound, either within or at the interface with another extruded layer.
Wet Location:
Installations under ground or in concrete slabs or masonry in direct contact with the earth; in locations subject to saturation with water or other liquids and in unprotected locations exposed to weather.
XLPE Insulation:
Crosslinked polyethylene insulation.
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ICE3 S-108-720-2004
Part 2 CONDUCTOR 2.0 GENERAL Conductors shall meet the requirements of the appropriate ASTM standards referenced in this standard except that resistance shall detemine cross-sectional area as noted in 2.4 and diameters shall be in accordance with 2.5. Requirements of a referenced ASTM standard shall be determined in accordance with the procedure or method designated in the referenced ASTM standard unless othewke specified in this standard. The following technical infomation on typical conductors may be found in Appendix G: a. Approximate diameters of individual wires in stranded conductos. b. Approximate conductor weights.
2.1 PHYSICAL AND ELECTRICAL PROPERTIES The conductors used in the cable shall be copper in accordance with 2.1.1 or aluminum in accordance with 2.1.2, as applicable, except as noted in 2.0. Conductors shall be stranded. The outer layer of a stranded copper conductor may be tin coated to assist with free stripping of the adjacent polymeric layer. There shall be no water in stranded conductors in accordance with 9.14. 2.1.I Copper Conductors 1. 2. 3. 4. 5. 6. 7. 8. 2.1.2
ASTM B 3 for soff or annealed uncoated copper. ASTM B 5 for electrical grade copper. ASTM B 8 for Class A, B, C, or D stranded copper conductors. ASTM B 33 for soft or annealed tincoated copper wire. ASTM B 496 for compact-round stranded copper conductors. ASTM B 784 for modified concentric lay stranded copper conductor. ASTM B 787 for 19 wire combination unilay-stranded copper conductors. ASTM B 835 for compact round stranded copper conductors using cingle input wire constructions.
Aluminum Conductors
ASTM B 230 for electrical grade aluminurn 1350-H19. ASTM B 231 for Class A, B,C, or D stranded aluminurn 1350 conductors. ASTM B 233 for electrical grade aluminum 1350 drawing stock. ASTM B 400 for compact-round stranded aluminum 1350 conductors ASTM B 609 for electrical grade aluminum 1350 annealed and intermediate tempers. ASTM B 786 for I 9 wire combination unilay-stranded aluminum 1350 conductors. ASTM B 800 for 8000 series aluminum alloy annealed and intermediate tempers. ASTM B 801 for 8000 series aluminum alloy wires, compad- round, compressed and concentric-lay Class A, B, C and D stranded conductors. 9. ASTM B 836 for compact round stranded aluminum conductors using single input wire constructions.
1. 2. 3. 4. 5. 6. 7. 8.
2.i.3
Special Conductors
Special conductors (segmental, etc.) shall be made up according to characteristics and details of construction as agreed to by the manufacturer and purchaser.
6
ICEA S-108-720-2004
DATE 7/15/04 9
2.1.3.1 Segmental Conductors Each segment shall conform, as to the number of individual strand splices, to the requirements of ASTM B 8 or B 231 whichever is applicable. Binder tapes when used, shall be nonmagnetic and shall have sufficient mechanical strength so that they can be applied with tension adequate to minimize the displacement of the segments. Binder tapes shall be applied substantially free of indents, mases, tears or whkles. Defects shall not be such that they protrude through the conductor shield. The eccentricity of cabled segmental conductors shall be determined from measurement of both maximum callipered and circumference tape diameters taken at five locations spaced approximately one foot (0.3 m) apart along the conductor. The average of the five maximum callipered diameters shall not exceed the average of the five circumference tape diameters by more than 2 percent. At any one location, the maximum callipered diameter shall not exceed the circumference tape diameter by more than 3 percent.
2.2 OPTIONAL SEALANT FOR STRANDED CONDUCTORS If required by the purchaser, a sealant designed as an impediment to longitudinal water penetration shall be incorporated in the interstices of the stranded conductor. Compatibility with the conductor shield shall be determined in accordance with ICEA Publication T-32-645. Longitudinal water penetration resistance shall be determined in accordance with ICEA Publication T-31-610 and shall meet a minimum requirement of 5 psig.
2.3 CONDUCTOR SIZE UNITS Conductor size shall be expressed by cross-sectional area in thousand circular mils (kcmil). metric equivalents for all sizes are described in Table 2-3 (Metric).
The
2ACONDUCTOR DC RESISTANCE The dc resistance per unit length of each conductor in a shipping length of completed cable shall not exceed the value 2% greater than the appropriate nominal value specified in Table 2-2. The dc resistance shall be determined in accordance with 2.4.1 or 2.4.2. For conductor strandings or sizes not listed in Tables 2-2, the nominal direct current resistance per unit length of a completed single conductor cable shall be calculated from the factors given in Table 2-5 using the following formula:
f x 10” R =A Where:
R = Conductor resistance in Ni000 R. f = Factor from Table 2-5 A = Cross-secîbnalarea of conductor in kcmil, determined in accordance with 9.3.2 Where the outer layer of a stranded copper conductor is coated, the direct current resistance of the resulting conductor shall not exceed the value specified for an uncoated conductor of the same size. 2.4.1
Direct Measurement of dc Resistance Per Unit Length
The dc resistance per unit length shall be determined by dc resistance measurements made in accordance with 9.3.1 to an accuracy of 2 percent or better. If measurements are made at a temperature other than 25 OC,the measured value shall be converted to resistance at 25 OC by using either of the following:
7
KEA S-108-720-2004
DATE: 7/15/04 4 Y
1. The appropriate multiplying factor obtained from ICEA T-27-581/NEfvíA WC-53. 2. A multiplying factor calculated using the applicable formula in ICEA T-27-581MEMA WC-53.
If verification is required for the directcurrent resistance measurement made on an entire length of completed cable, a sample at least Ifoot (0.3 m) long shall be cut from that reel length, and the directcurrent resistance of each conductor shall be measured using a Kelvin-type Bridge or a potentiometer. 2.4.2
Calculation of dc Resistance Per Unit Length
The dc resistance per unit length at 25 OCshall be calculated using the following formula:
R=K.-P A Where: R = Conductor resistance in W l O00 ft K = Weight increment factor, as given in Table 2-1. p = volume resistivity in Q-cmil/ft,determined in accordance with ASTM B 193 using round wires (see Table 2-5) A = Cross-sectional area of conductor in kcmil, determined in accordance with 9.3.2. When the volume resistivity is expressed in nanoohm meters (rS2.m) and area is expressed in square millimeters (mm') the resistance is expressed in milliohms per meter ( d m ) .
2SCONDUCTOR DIAMETER The conductor diameter shall be measured in accordance with 9.3.3. The diameter shall not differ from the nominal values shown in Table 2-3 by more than f 2 percent.
Table 2-1 Weight Increment Factor;
-
Conductor TypeiSUe
Weight Factor (K)
Ail Sizes
1
Concentric-lay Strand, Class A, B, C and D 250 - 2000 kcmil (127- IO13 mm2) >2000 3000 kcmil (>IO13 - 1520 mm') >3000 4000 kcmil (> 520I - 2027 mm2)
-
I.o2 I.O3 1.o4
Combination Unilay Strand All Sizes
1.oz
Concentric-lay Strand 8000 Series Aluminum All Sizes
I.o2
8
ICEA S-108-720-2004
DATE: 7/15/04
Table 2-2 Nominal Direct Current Resistance in Ohms Per 1000 Feet at 25 OC of Concentric Lav Stranded and Seamental Conductor
I
I
Conductor Size kcmil
I
Concentnc Lay Stranded’ Aluminum
I
I
Copper Uncoated
Class B,C,D
Segmental
ClassC
CiassD
0.0431 0.0360 0.0308
0.0448
0.0448 0.0374 0.0320
0.0448 0.0374 0.0320
...
0.0269
0.0277 0.0246
0.0280
0.0204 0.01 87
0.0280 0.0249 0.0224 0.0204 0.01 87
...
0.0249 0.0224 0.0204 0.0187
0.0707
300
0.0590
350
0.0505
400 450
0.0442 0.0393 0.0354 0.0321 0.0295
0.0240 0.0216 0.0196 0.0180
700 750 800 900
0.0272 0.0253 0.0236 0.0221 0.0196
0.0166 0.01 54 0.0144 0.0135 0.01 20
0.0171 0.0159 0.0148 0.0139 0.0123
0.0172 0.0160 0.0149 0.0140 0.0126
1o00 1100 1200 1250 1300
0.0177 0.0161 0.0147 0.0141 0.0136
0.0108 0.00981 0.00899 0.00863 0.00830
0.01 11 0.0101 0.00925
0.00888 0.00854
0.01 11 0.0102 0.00934 0.00897 0.00861
1400 1500 1600 1700 1750
0.0126
0.00634
0.00793 0.00740 0.00694 0.00653
0.00793 0.00740 0.00700 0.00659
0.00616
0.00634
0.00640
550 600
650
~~
0.0222
~
0.01 11 0.0104 0.0101 ~~
~
~
1800 1900 2000 2250 2500
0.00982 0.00931 0.00885 0.00794 0.00715
0.00599 0.00568 0.00539 0.00436
0.00616 0.00584 0.00555 0.00498 0.00448
2750 3000 3250 3500 3750 4000
0.00650 0.00596
0.00396 0.00363 0.00338 0.00314 0.00293 0.00275
0.00408 0.00374 0.00348 0.00323 0.00302 0.00283
0.00555 0.00515
0.00481 0.00451
0.00484
ConcenMc lay stranded includescompressed and compact conductors.
9
...
...
0.0173 0.0160 0.0150 0.0140 0.0126
...
...
0.0112 0.0102 0.00934 0.00897 0.00862
0.0177 0.0161 0.0147 0.0141 0.0136
...
... ... ...
I..
... ...
...
...
0.0126 0.0118 0.0111 0.0104
0.0101 ~
0.00622 0.00589 0.00560
...
... _..
... ...
...
... ...
...
...
-~
...
...
...
0.0108 0.00981 0.00899 0.00863 0.00830
-~
0.00801 0.00747 0.00700 0.00659 0.00640
.*.
...
...
... ...
~~~
0.00616 0.00584 0.00555
... ...
~~
~
... ...
... ... ...
~~
0.00771 0.00719 0.00674
0.01 18
~
0.0374 0.0320
Copper Uncoated
Class6
class B,C,D
250
500
1 Aluminum
coated
... ...
0.00771 0.00719 0.00674 0.00634 0.00616 ~
0.00982 0.00931 0.00885 0.00794 0.00715
0.00599 0.00568 0.00539
0.00650 0.00596 0.00555 0.00515 0.00481 0.00451
0.00396 0.00363 0.00338 0.00314 0.00293 0.00275
0.00484 0.00436
KEA S-I 08-720-2004
DATE: 7/15/04
Nominal Direct Current Resistance in Milliohms Per Meter at 25 OC of Concentric Lav Stranded and Seamental Conductor Concentric ay stranded' Segmentai Condudor Size
copper
Aluminum Uncoated
kmil
mm'
ClassB,C,D
Afuminum
coated
UassB,C,D
CiassB
ClassC
ClassD
250 300 350
127 152 177
0.232 0.194 0.166
0.141 0.118 0.101
0.147 0.123 0.105
0.147 O. 123 0.105
0.147 O. 123 0.105
400 450 500 550 600
203 228 253 279
0.145 0.129 0.116 0.105 0.0968
0.0882 0.0787 0.0708 0.0643 0.0590
0.0909 0.0807 0.0728 0.0669 0.0613
0.0918 0.0817 0.0735 0.0669 0.0613
0.0918 0.081 7 0.0735 0.0669 0.061 3
650 700 750
329 355 380
0.0544 0.0505
0.0561
0.0564
0.0522
405
900
456
0.0472 0.0443 0.0394
0.0485 0.0456 0.0403
0.0525 0.0489
800
0.0892 0.0830 0.0774 0.0725 0.0643
0.0567 0.0525 0.0492 0.0459 0.0413
0.0354
0.0364 0.0331 0.0303 0.0291 0.0280
0.0364 0.0335
608 633 659
0.0581 0.0528 0.0482 0.0462 0.0446
1400 1500 1600 1700 1750
709 760 811 861 887
0.0413 0.0387 0.0364 0.0341 0.0331
0.0253 0.0236 0.0221 0.0208 0.0202
1800 1900 2000
912
2500
1013 1140 1266
0.0322 0.0305 0.0290 0.0260 0.0235
2750 3000 3250 3500 3750 4000
1393 1520 ia7 1773 1990 2027
0.0213 0.0196 0.0182 0.0169 0.0158 0.0148
1O00 1100 1200 1250 1300
2250
304
507
557
963
0.0459 0.041 3
copper Uncoated
...
... ... ... ...
... ...
... ... ... ... ... ...
... ... ... ... ... ... ... ... ...
... ...
... ...
0.0581 0.0528
0.0294 0.0282
0.0367 0.0335 0.0306 0.0294 0.0283
0.0260 0.0243 0.0228 0.0214 0.0208
0.0260 0.0243 0.0230 0.0216 0.021 o
0.0263 0.0245 0.0230 0.0216 0.0210
0.0413 0.0387 0.0341 0.0331
0.0253 0.0236 0.0221 0.0208 0.0202
0.0196 0.0186 0.0177 0.0159 0.0143
0.0202 0.0192 0.0182 0.0163 0.0147
0.0202 0.0192 0.0182
0.0204 0.0193 0.0184
0.0322 0.0305 0.0290 0.0260 0.0235
0.0196 0.0186 0.0177 0.0159 0.0143
0.0130 0.0119 0.01 11 0.0103 0.0096 0.0090
0.0134 0.0123 0.0114 0.01 06 0.0099 0.0093
0.0213 0.0196 0.0182 0.0169 0.0158 0.0148
0.0130 0.0119 0.0111 0.0103 0.0096 0.0090
0.0322 0.0295 0.0283 0.0272
Concentric lay stranded includes compressed and compact condudors.
10
0.0306
... ... ... ... ... ... ... ...
...
... _.. -..
...
... ...
...
0.0482 0.0462 0.0446
0.0364
0.0354 0.0322 0.0295 0.0283 0.0272
ICEA S-108-720-2004
DATE: 7115104
Table 2-3 Nominal Diameters for Round Copper and Aluminum Conductors Condudor Sie
NominalDiameters(Inches)
I
concentric Lay stranded
Combination
Unilay
Class C
Class D
Unilay
Compressed
kmil
Compact'
400 450 500 550 600 650 700 750 800 900
0.520 0.570 0.616
0.61 1 0.661
0.575 0.630 0.681
0.576 0.631
0.576 0.631 0.682
0.554 0.607 0.656
0.542 0.594 0.641
0.659 0.700 0.736 0.775 0.813
0.706 0.749 0.789 0.829 0.866
0.728 0.772 0.813 0.855 0.893
0.729 0.773 0.814 0.855 0.893
0.729 0.773 0.815 0.855 0.893
0.701 0.744 0.784
0.685
0.845 0.877
0.901 0.935 0.968 1.o00 1.o61
0.929 0.964 0.998 1.031 1.o94
0.930 0.965 0.999 1.O32 1.O93
0.930 0.965 0.998 1.O32 1.O95
... ...
1.117 1.173 1.225 1.251 1.276
1.152 1.209 1263 1.289 1.315
1.153 1.210 1264 1.290 1.316
1.153 1.211 1.264 1.290 1.316
... ...
1.364
1.365 1.413 1.460 1.504 1.527
...
1.459 1.504 1.526
1.365 1.413 1.460 1.504 1.527
1.502 1.542 1.583 1.678 1.769
1.548 1.590 1.632 1.730 1.a24
1.548 1.590 1.632 1.731 1.824
1.%9 1.591 1.632 1.731 1.824
...
1.ô56 1.938 2.018 2.094 2.168 2.240
1.914 1.998 2.081 2.159 2.235 2.309
1.914 1.999 2.081 2.159 2236 2.309
1.914 1.999 2.081 2.1 58 2.234 2.309
0.908 0.938 0.999
1O00 1100 1200 1250 1300
1.o60
1400 1500 1600 1700 1750
...
1800 1900 2000 2250 2500
... ...
2750 3000 3250 3500 3750 4000
... ... ... ... ...
...
...
...
...
... ...
... ...
...
... ...
...
1.323 1.370 1.415 1.459 1.480
1.412
Diameters shown are for compact round, compact modified concentric and compact single input wire. Diameters shown are for conœnbic round and mod$ed concentric.
...
...
... ...
... ...
... ... ... ...
...
...
...
...
0.727 0.766
0.804 0.840 0.874 0.907 0.939 0.969 1.O28 1.o84 1.137 1.187 1.212 1.236 1.282 1.327 1.371 1.413 1.434 1.454 1.494 1.533
... ...
...
...
-.. ...
...
...
... ...
...
... ... ...
...
...
ICEA S-108-720-2004
DATE: 7/15/04
Table 2-3 (Metric) Nominal Diameters for Round Copper and Aluminum Conductors I
I
Conductor Sue
I
Nominal Diameten (mm)
kcmil
Concentric Lay Stranded
mm'
'
'
Compact'
Compressed
CiassB"
Class c
class D
Combination Unilay
Unilay Compressed
14.2 15.5 16.8
14.6 16.0 17.3
14.6 16.0 17.3
14.6 16.0 17.3
14.1 15.4 16.7
13.8 15.1 16.3
17.8 18.9 19.9
17.4 18.5 19.5 20.4 21.3
250 300 350
127 152
in
13.2 14.5 15.6
400 450 500 550
600
203 228 253 279 304
16.7 17.8 18.7 19.7 20.7
17.9 19.0 20.0 21.1 22.0
18.5 19.6 20.7 21.7 22.7
18.5 19.6 20.7 21.7 22.7
18.5 19.6 20.7 21.7 22.7
650 700 750 800 900
329 355 380 405 456
21.5 22.3 23.1 23.8 25.4
22.9 23.7 24.6 25.4 26.9
23.6 24.5 25.3 26.2 27.8
23.6 24.5 25.4 26.2 27.8
23.6 24.5 25.3 26.2 27.8
1000 1100 1200 1250 1300
507 557 608 633 659
26.9
28.4 29.8 31.1 31.8 32.4
29.3 30.7 32.1 32.7 33.4
29.3 30.7 32.1 32.8 33.4
29.3 30.8 32.1 32.8 33.4
1400 1500 1600 1700 1750
709 760 811 861 887
... ... ...
33.6 34.8 35.9 37.1 37.6
34.6 37.1 38.2 38.8
34.7 35.9 37.1 38.2 38.8
34.7 35.9 37.1 38.2 38.8
1800
912 963 1013 1140 1266
... ... ...
38.2 39.2 40.2 42.6 44.9
39.3 40.4 41.5 43.9 46.3
39.3 40.4 41.5 44.0 46.3
39.3 40.4 41.5 44.0 46.3
...
47.1 49.2 51.3 53.2 55.1 56.9
48.6 50.7 52.9 54.8 56.8 58.6
48.6
48.6 50.8 52.9 54.8 56.7 58.6
I
2250 2500
1
2750
1
3000 3250 3500 3750 4000
1393 1520 1647 1773 1990 2027
... ... ... ...
... ...
... ... ... ... ... ...
... ..,
35.9
50.8 52.9 54.8 56.8 58.6
Diameten shown are for compact rwnd. compact modified concentricand compact cingle input wire. ** Diameters shown are for concentricround and modified concentric.
12
... ... ... 1..
... ... ... ... ... ...
... ... ... ... ...
... ...
22.2 23.0 23.9 24.6 26.1 27.5 28.9 30.1 30.8 31.4 32.6 33.7 34.8 35.9 36.4
...
36.9 37.9 38.9
...
...
_._
...
...
... ...
...
...
... ...
...
... ... ... ... ...
DATE: 7/15/04
ICEA S-108-720-2004
Copper and Aluminum Conductors Segmental Conductor Diameter
Condudor Sue kanil
(Four segments) mrn’
Inches
mrn
1o00 1100 1200 1250 1300
507 557 608 633 659
1.140to 1.152 1.195to1.209 1.235 to 1.263 1.260 to 1.289 1285 b 1.315
29.0 to 29.3 30.4 to 30.7 31.4 to 32.1 32.0 to 32.7 32.6 b 33.4
1400 1500 1600 1700 1750
709 760 811 861 887
1.325 to 1.364 1.375 to 1.412 1.420 to 1.459 1.46oto1.504 l.Wto1.526
33.7 to 34.6 34.9 to 35.9 36.1 ta 37.1 37.1 to 38.2 37.6 to 38.8
1800 1900 2000
912 963 1013 1140 1266
1.50Oto1.548 1S30to 1.590 1.570to1.632 1.665 to 1.730 1.740 to 1.824
38.1 to 39.3 38.9 t0 40.4 39.9 to 41.5 42.3 to 43.9 44.2 to 46.3
2250 2500
46.5 to 48.6
Table 24‘ Factorst for Determinina Nominal Resista ice of Stranded Conductors Per I000 Feet at 25 OC Diameter of Indidual Coated Copper Wires in Inches for Stranded Conductors
All sues Conductor S i z e
undero.290 to 0.103. Indusive
Under0.103 to 0.0201, Indusive
Under 0.0201 to 0.01 11, Indusive
Under 0.01 11 to 0.0010, Indusive
ConcentricStranded 250-2000kcmi1(127- 1013rnm2)
17692
10786
11045
11102
11217
11456
11580
> 2000 - 3000 kcmil (>lo13 - 1520 mm’)
17865
10892
11153
11211
11327
11568
11694
18309
1o998
11261
11319
11437
11680
11807
61
1O0
97.66
97.1 6
96.16
94.16
93.15
-
> 3000 4000 kcmil (21520 - 2027 mm’) Condudiviíy utilized for above fadors, Percent *
0.460 to 0.290. Indushre
~
The factors given in Table 2-5 shall be based on the following: A. Resistivity 1. A vdurne resistivity of 10.575 QmiVft (0.017580 Qmm’/m) at 25 Oc for uncoated (bare) copper (100% conducuviiy). 2. A 25 OCvolume resisüv&yconvertedfrom the 20 Oc values specified in ASTM B 33 for tin coated copper. 3. A volume resistivity of 17.345 tLcmiWt (0.028835 Qm2/m) at 25 OCb r aluminum (61.OYOconducuvity). 6. Increase in Resistance Due to Stranding 1. The value of K (weight increment factor) given in Table 2-1.
t See 2.4 for Use of Factors.
13
ICEA S-108-720-2004
DATE: 7/15/04
Part 3
CONDUCTOR SHIELD 3.1 MATERIAL The conductor shall be covered with an extruded thermosetting conductor shield material. A semiconducting tape may be used between the conductor and the extruded shield in which case it shall not be considered as part of the extruded shield thickness. The extruded material shall be either semiconducting or nonconducting for ethylene propylene rubber (EPR) type insulation and semiconducting only for crosslinked polyethylene (XLPE) type insulation. The extruded shield shall be compatible with all cable component materials with which it is in contact. The allowable operating temperatures of the conductor shield shall be equal to or greater than those of the insulation. The conductor shield shall be easily removable from the conductor and the outer surface of the extmded shield shall be firmly bonded to the overlying insulation.
3.2 EXTRUDED SHIELD THICKNESS (See 9.4.2). The extruded conductor shield minimum thickness shall be as follows: Table 3-1 Extruded Conductor Shield Thickness
3.3 PROTRUSIONSAND IRREGULARITIES (See 9.4.13). The interface between the extruded conductor shield and the insulation shall be cylindrical and free from protrusions and irregularities that extend more than 3 mils (0.076 mm) into the insulation and 3 mils (0.076 mm) into the extruded conductor shield.
3.4VOIDS (See 9.4.13). The interface between the extruded conductor shield and the insulation shall be free of any voids larger than 2 mils (0.051 mm).
14
DATE: 7115/04
ICEA S-108-720-2004
3.5 PHYSICAL REQUIREMENTS The crosslinked material(s) intended for extnision as a conductor shield shall have an elongation of no less than 100 percent after air oven aging for 168 hours at 121 OC11 OCfor insulations rated 90 OC(see 9.4.14). It shall also meet brittleness requirements (see10.3.4) at temperatures not warmer than -25 OC.
3.6 ELECTRICAL REQUIREMENTS 3.6.1
Extruded Semiconducting Material
(See 9.8.1). The volume resistivity of the extruded semiconducting conductor shield shall not exceed 1000 ohm-meter at the maximum normal operating temperature and emergency operating temperature. 3.6.2
Extruded Nonconducting Material (For EPR Insulation Only)
The extnided nonconducting conductor shield shall withstand a 2.0 kV dc spark test and meet the following requirements at room temperature, at the maximum normal operating temperature, and emergency operating temperature: Dielectric Constant, range
8 - 200
Minimum 60 Hz ac voltage withstand stress
kVlmm=
3.6.3
60 dielectric constant
Semiconducting Tape
If a semiconducting tape is used over the conductor, the dc resistance of the tape at room temperature shall not exceed 10,000 ohms per unit square when determined in accordance with ASTM D 4496.
3.7 WAFER BOIL TEST (See 9.4.12). The extruded conductor shield shall be crosslinked.
15
ICEA SI08-720-2004
DATE: 7/15/04
Part 4 INSULATION
4.1 MATERIAL The insulation shall be one of the following materials meeting the dimensional, electrical, and physical requirements specified in this section:
. Crosslinked polyethylene (XLPE) with no mineral fillers
- Ethylene propylene rubber (EPR)
Crosslinked polyethylene is suitable for dry locations and wet locations w-rth radial water bamer at voltages above 46 up to and including 345 kV between phases. Ethylene propylene rubber insulation has two classifications. Class I is for Discharge-Free and DischargeResistant designs. Class II is for Discharge-Free designs only. Ethylene propylene rubber insulation is suitable for wet or dry locations at voltages above 46 up to and including 138 kV between phases. The conductor temperature shall not exceed the following: Table 4-1 Conductor Maximum Operation Temperatures Insulation Matenalt
Normal Operation
Rated ~
I -
I
XLPE and EPR Classes 1, II
Greater than 46 through 138 kV
XPE
Greater than 138 through 345 kV
I
90 oc
oc
Short Circuit*
Emergency Overload' I
105 to 130 OC
250 OC
105 OC
250 OC
*See Appendix 6 Tondudor fault current may be determined in accordance with ICE3P-32-382. tOther insulation materials composed of Eîhylene and Alkene units, which are designated as EAM, may be available and can meet the same physical and electrical requirements as the insulation materials described in t h i s standard. See AppendM H andlor contadthe manufadursr for further information.
4.2 INSULATION THICKNESS The nominal insulation thicknesses shall be designed based on electrical stress. The electrical stress at the conductor shall not exceed the values given in Table 4-2 or the stress qualified by the manufacturer whichever is lower. The stress limits are based on rated voltage, given in Table 4-2. The manufacturer shall specify the nominal wall to be supplied. The minimum point thickness shall be not less than 90 % of the specified nominal wall thickness. Gmax
= vg I(& x in
Where: G, = Maximum stress at the conductor shieldlinsulation interface (kVlmm) 'V = Nominal voltage to ground (kV)
16
DATE: 7115/04
ICEA S-108-720-2004 Ri = Nominal radius over the insulation (mm) Rs= Nominal radius of the conductor shield/insulation interface (mm).
Traditional insulation thicknesses are listed in appendix F. 4.2.1
Selection of Insulation Thickness
The nominal insulation thickness is calculated by using the lower value of the maximum voltage stress from Table 4-2 for the appropriate voltage dass or the maximum voltage stress qualified by the manufacturer. Maximum stress levels in Table 4-2 assume the actual operating voltage shall not exceed the rated voltage by more than 5 percent during continuous operation or 10 percent during emergencies lasting not more than 15 minutes. Either the 15 minute, 30 minute or 60 minute ac test is required. Ac test levels for the appropriate rated voltage are to be used as the basis for ac testing should insulation stresses other than those in Table 4-2 be utilized.
All ac tests shall be conducted at room temperature and at power frequency (49-61 Hz). The waveform shall be substantially sinusoidal. All ac voltages are rms values. For other voltage ratings and conductor sizes, specific agreement between purchaser and manufacturer in the selection of insulation maximum stress for each application is required. There may also be unusual installations and/or operating conditions where mechanical considerations dictate the use of a larger insulation thickness. When such conditions are anticipated, the purchaser should consult with the cable manufacturer to determine the appropriate insulation thickness. It is recornmended that the minimum size conductor be in accordance with Table 4-2.
A threshold ac test limit of 27 kV/mm to 30 kV/mm should not be exceeded for some insulations (as specified by the manufacturer), in order to avoid any possible weakening of the insulation prior to delivery which might later cause a failure in service. The voltage maybe lowered, but with a correspondingly longer testing time in order to avoid too high stresses. However, the voltage level shall not be below 1.5 Vg and the duration not longer than 10 hours. Lower maximum stress may be required because of the type of cable joints and terminations or because of cable environment conditions. Consult cable manufacturer for further information. (See Appendix 04) The cable insulation stress specified is for application where the system is provided with circuit protection such that ground faults will be cleared as rapidly as possible, but in any case within one minute. While these cables are applicable to installations which are on grounded systems, they may also be used on other cable systems, provided the above deanng requirements are met in completely de-energizing the faulted section. In common with other electrical equipment, the use of cables is not recommended on systems where the ratio of the zero to positive sequence-phase reactance of the system at the point of cable application lies behiveen -1 and 4 0 since excessively high voltages may be encountered in the case of ground faults. r
17
ICEA S-i08-720-2004
Rated VomW,
kV 69
Ir
I IL
~-
11.5
I
120
DATE 7/15/04
Condudor Sire, kcmii
conctuáor Size,
2504000
127-2027
750-4000
StressLevel
x
kV1mm (Vlmii)
12
6 (152)
nun
I
7504000
380-2027
I
12
380-2027 I
I
Maximum Innitation Eccentricity
ac Test Voltaga
Insulation Maximum
I
81203)
30 Min. Test 2 5 Vg
60 Min. Test
vg kW
kv
i 5 Min. Test 3.0 Vg kV
80
100
120
2o
I
135
12
8 (203)
140
I
I j
-460
1 O L -1
175
205
200
240
138
750-4000
380-2027
12
8 (203)
160
161
7504000
3W2027
10
9 (229)
185
230
280
230
1
0
~ 507-2027
10
11 1279) . .
265
330
NIA
345
1000-4000
507-2027
10
16 (406)
400
PUA
4.2.2
0
Insulation Eccentricity
The eccentricity of the insulation layer shall not exceed the value given in Table 4-2 when calculated as shown below:
7' max-T min T max
1 00
Where Tmax and Tmin are maximum and minimum values measured around the same cable crosscedion.
4.3 INSULATION REQUIREMENTS 4.3.1
Physical and Aging Requirements
When tested in accordance with Part 9, the insulation shall meet the following requirements:
18
I .IIr
DATE: 7115104
ICEA S-108-720-2004 Table 4-3 Insulation Physical Requirements Insulation Type Physical Requirements
EPR Class
XLPE I
I
II
Unaged Requirements Tensile Strength, Minimum Psi (MPa)
1800 (12.5)
Elongation at Rupture Minimum Percent
1200 (8-2)
700 (4.8)
250
250
Aging Temperature, OC
121
121
Tensile Strength, Minimum Percentage of Unaged Value
75
75
80
Elongation, Minimum Percentage of UnagedValue
75
75
80
Aging Requirements After Air Oven Aging for 168 hours
Hot CreeD Test at 150 OCI2 OC *Elongation, Maximum Percent
175
50
*Set, Maximum Percent
10
5
'For XLPE insulationsif this value is exceeded, the Solvent ExtractionTest (ASTM D2765)may be performed and will serve as a referee method to detemine compliance (a maximumof 30 percent weight loss after 20 hour drying time).
4.3.2
Electrical Test Requirements
4.3.2.1 Partial-Discharge for Discharge-Free Designs only (See 9.12). Each shipping length of completed cable shall be subjected to a partial discharge test. The partial discharge shall not exceed the values in Table 4-4. The test voltages for partial discharge measurements are listed in Table 4-5. Table 4-4 Partial-Discharge Requirements
19
DATE: 7115/04
ICEA S-108-720-2004 Table 4-5 Test Voltages for Partial-Discharge Measurements Test Voltages (vt) in kV Corresponding to VtAfg Ratio
Cable Voltage Rating kV
4.3.2.2 Voltage Tests (See 9.1 1). Each shipping length of completed cable shall withstand, without failure, the ac test voltages given in Table 4-2. The test voltage shall be selected from the table based on the rated voltage of the cable. For purposes of this standard, the BIL value shall be in accordance with Table 4-6. Table 4-6 Impulse Values
BIL kV
Rated Voltage kV
I
H
I
69
I
350
115
I
550
120
550
138
650
161
750
230
1050
345
1300
I
4.3.2.3 Insulation Resistance Test (See 10.3.1). The insulated conductor shall have an insulation resistance not less than that corresponding to a constant (K) of 20,000 megohrns-1O00 ft at 15.6 OC.
20
DATE: 7115/04
ICEA S-108-720-2004
4.3.2.4 Dielectric Constant and Dissipation Factor The insulation shall meet the following maximum requirements for dielectric constant and dissipation factor at room temperature when tested in accordance with ICEA T-27-581/NEMA WC-53. Table 4-7 Dielectric Constant and Dissipation Factor InsulationType Properties
Dielectric Constant Dissipation Factor, Percent
I
XLPE
EPR Class I, II
3.5
4.0
o. 1
l
1.5
4.3.2.5 Discharge (Corona) Resistance for Discharge-Resistant EPR Designs only (See 10.3.5) The insulation shall be verified as corona discharge resistant using a 21 kV 60 Hz voltage applied for 250 hours. Neither a failure nor surface erosion visible with 15 times magnification shall occur. Partial discharge measurements are not required for DISCHARGE-RESISTANT cables. 4.3.3
Voids, Ambers, Gels, Agglomerates and Contaminants as Applicable
4.3.3.1 Crosslinked Polyethylene Insulation (XLPE) (See 9.4.13). The insulation of the sample examined shall be free from: 1) Any void larger than 2 mils (0.051 mm). The number of voids larger than 1 mils (0.025 mm) shall not exceed 30 per cubic inch (1.8 per cm’) of insulation. 2) Any contaminant larger than 5 mils (0.127 mm) in its greatest dimension and no more than 10 per cubic inch (0.6 per un3)between 2 and 5 mils (0.051 and 0.127 mm). 3) Any amber that is larger than 10 mils (0.254 mm) in its greatest dimension. 4.3.3.2 Ethylene Propylene Rubber (EPR) (See 9.4.1 3). The insulation of the sample examined shall be free from: 1) Any void larger than 4 mils (O. 1O2 mm).
2) Any contaminant, gel, or agglomerate larger than 10 mils (0.254 mm) in its greatest dimension. A distinction between contaminants, gels, and agglomerates is not required.
21
ICEA S-I 08-720-2004 4.3.4
DATE: 7/15/04
-
Shrinkback Crosslinked Polyethylene Insulation (XLPE) Oniy
(See 9.9). The conductor shall not protrude beyond the insulation (total of both ends) by more than the amounts shown in Table 4-8.
I
Oven Cycle
Total Shrinkback mils (mm)
1
O to 20 (0.51)
> 20 (0.51)
Action
Pass: TeminateTest Record and Continue Cyding Test
2
O to 40 (.O21 I > 40 (1.02)
Pass: Teminate Test Record and Continue Cycling
3
O to 300 (7.62) > 300 (7.62)
Pass: Terminate Test Fail: Terminate Test
22
1
DATE: 7/15/04
ICEA S-108-720-2004
Part 5 EXTRUDED INSULATION SHIELD
5.1 MATERIAL The insulation shield shall be an extruded thermosetting semiconducting material compatible with all cable components with which it is in contact. The extruded shield shall be readily distinguishable from the insulation and plainly identified as semiconducting.
5.2 THICKNESS REQUIREMENTS The thickness requirements for the extruded insulation shield are as indicated in Table 51. The minimum point thickness is applicable at all locations. Table 5-1 Insulation Shield Thickness
1
Calculated Minimum Diameter Over the Insulation inches (mm)
1
Insulation Shield Thickness Minimum Point
Maximum Point
mils
mm
mils
mm
(O - 50.80)
40
1.o2
80
2.03
2.001 and larger (50.83 and larger)
40
1.o2
100
2.54
o - 2.000
I
5.3 PROTRUSIONS AND IRREGULARITIES (See 9.4.13). The interface between the extruded insulation shield and the insulation shall be cylindrical and free from protrusions and irregularities that extend more than 5 mils (0.1 27 mm) into the insulation and 5 mils (0.127 mm)into the extruded insulation shield.
54SEMICONDUCTING TAPE If a semiconducting tape is utilized over the extruded insulation shield, the dc resistance of the tape at room temperature shall not exceed 10,000 ohms per unit square when determined in accordance with
ASTM D 4496.
5.5 INSULATION SHIELD REQUIREMENTS 5.5.1
Removability
The insulation shield shall be bonded firmly and continuously to the insulation.
23
ICEA S-108-720-2004 5.5.2
DATE: 7115/04
Voids
(See9.4.13). The interface between the extruded insulation shield and the insulation shall be free of any voids larger than 2 mils (0.05 mm). 5.5.3
Physical Requirements
The material@) intended for extrusion as an insulation shield shall have an elongation of no less than 100 percent after air oven aging for 168 hours at 121 OC.I1 OCfor insulations rated 90 OC(see 9.4.14). It shall also meet brittleness requirements (see 10.3.4) at temperatures not warmer than -25 OC. 5.5.4
Electrical Requirements
(See 9.8.2). The volume resistivity of the extruded insulation shield shall not exceed 500 ohmmeter at the maximum normal operating temperature and at a temperature of 110 OCfor cables with an emergency overload temperature rating of 130 OC.
5.5.5
Wafer Boil Test
(See 9.4.1 2). The extruded thermoset insulation shield shall be crosslinked.
24
DATE: 7/15/04
ICEA S-108-720-2004
Part 6 METALLIC SHIELDING
6.1 GENERAL A nonmagnetic metallic shielding consisting of a shield, sheath or combination thereof shall be applied over the nonmetallic semiconducting layer. The metal shieldsheathshall be electrically continuous and free of burrs throughout each cable length. The metal shieldsheath shall be applied in such a manner that electrical continuity or contiguity will not be distorted or disrupted during normal installation bending. The metal shieldlsheath should be designed to withstand the specified fault current and duration duty of the cable system’s protective relaying and fault interrupting devices (see 1.3.1 .e).
A bedding layer such as semiconducting tapes may be used over the extruded insulation shield to insure cable core expansion without damage to the metallic shield or cable core. The bedding layer shall be Semiconducting and meet the requirements of part 5. Metallic shielding types indicated as a sheath in 6.3 below are considered to meet the requirement of a radial moisture bamer in 6.4. Metallic shielding types indicated as a shield in 6.2 below are not considered to meet the requirements of a radial moisture bamer in 6.4 without additional sealing components. Note: The purchaser is cautioned that a metallic shieldlsheath meeting the specified minimum requirements shown in 6.2 and 6.3 below does not necessarily have sufficient fault current withstand capability for all system faults. Coordination is required with worst case protective relaying and circuit breaker performance while considering the cases of a fault within the cable system and external to it. ICEA Publication P-4.5-482 may be used to determine metallic shieldkheathfault-clearing capability.
6.2 SHIELDS 6.2.1
HELICALLY APPLIED TAPE SHIELD
A tin coated or uncoated copper tape shall be at least 0.0045 inches (0.11 mm) thick and applied helically in intimate contact with the underlying semiconducting layer. Other nonmagnetic metal tapes having equivalent conductance may be used upon agreement between the manufacturer and purchaser. Joints in the tape shall be made electrically continuous by welding, soldering, or brazing. Butted tapes shall not be permitted. Tape(s) shall be lapped by at least 10% of the tape width or may be gapped by a maximum of 20% and a minimum of 5 % of the tape width. The direction of lay may be right-hand or left-hand.
6.2.2
LONGITUDINALLY APPLIED AND OVERLAPPED CORRUGATED TAPE
A IOngitUdiMlly applied corrugated tape shield shall be annealed copper. The minimum thickness of the corrugated tape shield before corrugation shall be 0.0075 inches (0.19 mm). Joints in the tape shall be made electfically continuous by welding, soldering, or brazing. The width of the corrugated tape shield shall be such that after corrugation the edges shall overlap by not less than 0.375 inches (9.5 mm) when the tape is longitudinally formed over the insulated core. The corrugation shall be at right angles to the axis of the cable, shall coincide exactly at the overlap, and shall be in contact with the underlying semiconducting layer. 6.2.3
WIRE SHIELD
A wire shield shall consist of a serving of tin coated or uncoated copper wires applied helically or longitudinally in intimate contact with the underlying Semiconducting layer. The minimum wire size shall be 18 AWG. The minimum number of wires shall be based on a maximum calculated spacing between wires of
25
ICEA S-108-720-2004
DATE: 7/15/04
0.5 inches (12.7 mm). The length of lay of the helically applied wire shield shall be not less than six times nor greater than ten times the calculated minimum diameter over the wire shield. The diredion of lay may be right-hand or left-hand. 6.2.4
FLAT STRAP SHIELD
A flat strap shield shall consist of a serving of tin coated or uncoated copper straps applied helically in intimate contact with the Underlying semiconducting layer. The minimum thickness of flat straps shall be 0.020 inches (0.51 mm) and the width of the strap shall not be less than three times the strap thickness. The minimum number of flat straps shall be based on a maximum calculated spacing between straps of 0.5 inches (12.7 mm). The length of lay of the flat strap shield shall be not less than six times nor greater than ten times the calcuiated minimum diameter over the flat strap shield. The direction of lay may be right-hand or left-hand.
6.3 SHEATHS 6.3.1
LEAD SHEATH
A sheath of lead alloy (see Appendix I) shall be tightly fonned over the underlying semiconducting layer. The thickness of the lead sheath shall be in accordance with Table 6-1 except when a higher value is required in order to meet the fault current requirement. Table 6-1
Lead Sheath Thickness
6.3.2
SMOOTH ALUMINUM SHEATH
The sheath shall be aluminum alloy 1060 or 1350 or other alloy having not less than 99.45 % aluminum. The aluminum sheath shall be tightly formed around the core of the cable. A smooth sheath shall be constructed by using a flat metal tape that is longitudinally folded around the cable core and seam welded or by applying over the cable core a seamless sheath or tube. The manufacturer shall determine the alloy unless otherwise agreed upon between the manufacturer and the purchaser. The thickness of the aluminum sheath shall be at least 0.020 inches (0.51 mm). 6.3.3
CONTINUOUSLY CORRUGATED SHEATH
Continuously corrugated sheath shall be constructed by using a flat metal tape that is longitudinally
26
DATE: 7/15/04
ICEA S-108-720-2004
folded around the cable core, seam welded, and corrugated or by applying over the cable core a seamless sheath or tube which is then corrugated. when metal sheath is formed from a flat metal tape, the tapes used shall be aluminum, aluminum alloy having not less than 99.45 % aluminum or copper. When the metal sheath is formed by applying a seamless sheath or tube the metal shall be aluminum or an aluminum alloy having not less than 99.45 % aluminum. The thickness of the aluminum sheath shall be at least 0.032 inches (0.81 mm). The thickness of the copper sheath shall be at least 0.020 inches (0.51 mm).
6.4 RADIAL MOISTURE BARRIER Crosslinked polyethylene cables with insulations designed by maximum stress criteria that are intended for wet locations shall incorporate a radial moisture bamer. A radial moisture bamer is optional for ethylene propylene rubber insulated cables. Nso, a radial moisture bamer is optional for crosslinked poiyethyiene insulated cables intended for dry locations. Radial moisture bamers include metallic sheaths, bonded metallic foil laminates, or other alternate designs as agreed upon between the purchaser and manufacturer. When requested the manufacturer shall demonstrate the effectiveness of the radial moisture bamer.
6.5 OPTIONAL LONGITUDINALWATER BLOCKING COMPONENTS with the approval of the purchaser, any component(s) designed as an impediment to longitudinal water penetration may be incorporated in the interstices andlor the interfaces of the metallic shieldsheath. If the component is a tape and is applied under the metallic shieldlsheath or between different metallic shieldlsheath members for composite metallic shieldsheaths, it must be semiconduciing and meet the requirements of 5.4. Longitudinal water peneíration resistance shall be determined in accordance with ICEA Publication T-34-664 and shall meet a minimum requirement of 5 psig.
27
ICEA S-I 08-720-2004
DATE 7/15/04
Part 7 JACKET 7.1 MATERIAL The jacket shall consist of a nonconducting thermoplastic material. Jackets are required for all constructions unless otherwise agreed upon between the purchaser and manufacturer. The jacket matenal shall be compatible with all cable components it contacts. A thermosetting jacket or other jacket materials may be supplied upon consulting the manufacturer. When tested in accordance with Part 9, the jacket shall meet the applicable requirements. There shall be no water between underlying layers and the jacket in accordance with 9.14. 7.1.1
Polyethylene, Black
This jacket shall consist of a black, low density (LDPE), linear low density (LLDPE), medium density (MDPE) or high density (HDPE) polyethylene compound suitable for exposure to sunlight The jacket shall meet the following requirements. Jacket irregularity inspection test shall be performed in accordance with 7.4 (See Tables 7-4 and 7-5). Table 7-1 Polyethylene, Black
Tensile Strength, Minimum Percentage of Unaned Value
75
75
75 ~
Elongation, Minimum Percentage of Unaged Value
~
75
75
75
Heat Distortion, Maximum 30 percent at
100 o c I1 o c
11OOC*l oc
110 oc Iloc
Environmental Stress Cracking
No Cracks’
No Cracks**
No Cracks**
Absorption Coefficient Minimum 1OOO(absorbance/meter)
320
320
320
Base Resin Density (DZx,g/cm3)*
0.910 - 0.925
0.926 - 0.940
0.941- 0.965
28
DATE: 7/15/04
ICEA S-108-720-2004
7.1.2
Polyvinyl Chloride
This jacket shall consist of a black, polyvinyl chloride (PVC) compound suitable for exposure to sunlight. The jacket shall meet the following requirements. Jacket irregularity inspection test shall be performed in accordance with 7.4 (SeeTables 7 4 and 7-5).
Table 7-2 Polyvinyl Chloride Values
Physical Requirements
Tensile Strength, Minimum
1500 (10.3)
Pi (MW Elongation at Rupture Minimum Percent
1 O0
Tensile Strength, Minimurn Percentage of Unaged Value
80
Elongation, Minimum Percentage of Unaged Value
60
Heat Distortion at 121 OCi1 OC
50
Maximum Percent
1 Heat Shock at 121 OC11 OC
I
1
I
Cold Elongation at -35OC Minimum Percent
29
NoCracks
20
DATE 7l15104
ICEA S-108-720-2004
7.2 JACKET APPLICATION AND THICKNESS The jacket material shall be applied over the metallic shieldsheath or a separator tape which is compatible with the other components of the cable. If a separator tape is applied over the metallic shieldkheath, the tape may be either nonconducting or semiconducting. Jacket thickness shall be as stated in 7.2.1 or 7.2.2. 7.2.1
Thickness of Jacket for Tape and Wire Shields
The jacket thickness shall be measured over the outer most point of the metallic shield and shall meet the thickness requirements in Table 7-4. The separator tape, if present, shall not be included as part of,the jacket thickness. 7.2.2
Thickness of Jacket for Sheaths
The jacket thickness shall be measured over the outer most point of the metallic sheath and shall meet the thickness requirements in Table 7-5. The separator tape, if present, shall not be included as part of the jacket thickness.
7.3 OPTIONAL SEMICONDUCTING COATING An optional semiconducting coating may be applied to the outer surface of nonconductingjackets to aid
in performing integrity test of the jacket in the field aíter installation. This coating may be graphite or other suitable material. If this coating is applied, the jacket shall be tested with a dc voltage in lieu of spark testing, If an extruded semiconducting layer is utilited and the properties of that layer meet either types in Table 7-3 then the thickness of the extruded semiconducting layer can be considered an integral patt of the total jacket thickness provided it does not exceed 20% of the total jacket thickness.
7.4 JACKET IRREGULARITY INSPECTION 7.4.1
Jackets without Optional Semiconducting Coating
A jacket over the metallic shieldsheath without a semiconducting coating shall withstand an alternating current spark test voltage. The test voltage for a given thid
Jackets with Optional Semiconducting Coating
The jacket shall withstand a dc voltage of 200 Vlmil(8 kV/mrn) of the average value of the specified minimum point and maximum point thickness of thejacket in Tables 7-4 and 7-5 with a maximum of 25 kV between the metallic sheath or shield and the semiconducting outer coating for a period of one minute.
30
ICEA S-108-720-2004
DATE: 7115104 Table 7-3 Semiconducting Extruded Jacket Coating
Tensile Strength, Minimum psi (MPa)
1200 (8.27)
1500 (10.3)
Elongation at Rupture Minimum Percent
1O0
150
After Air Oven Aging at
100 OCilOCfor 48 hours
121 OCI I OCfor 168 hours
Tensile Strength, Minimum Percentage of Unaged Value
75
75
Elongation, Minimum Percentage
1O0
75
~~
90 oc tl o c
Heat Distortion. Maximum 25 Dercent at ~~
121 oc +_I 'OC
~~
Volume Resistivity At 25 OCi5 OC
I
1O0
Maximum ohm-meter Brittleness Temperature
1O0
-1o
OC,not warmer than
-15
Table 7-4 Jacket Thickness and Test Voltages for Tape or Wire Shield Cables Calculated Minimum Diameter Over the Metallic Shield Inches (mm)
I
I
Jacket Thickness
L
MinimumPoint
Maximum Point
I
I
-
AC SDark Test Voltaae for Noncond"&ng Jacke&
mils
mm
mils
mm
kV
O - 2.500 (O - 63.50)
1O0
2.54
150
3.81
10.0
2.501 and larger (63.53 and larger)
125
3.18
185
4.70
12.5
31
ICEA S-108-720-2004
DATE: 7115l04
2.251 3.000 (57.1 8 76.20)
-
85
2.16
135
3.43
7.5
3.001 and larger (76.23 and larger)
1O0
2.54
160
4.06
10.0
*
32
DATE: 7/15/04
ICEA S-I 08-720-2004
Part 8 CABLE IDENTIFICATION 8.1 CABLE IDENTIFICATION The outer jacket surface of the cable shall be suitably marked throughout its length by indent print or emboss print to a depth not greater than 15 percent of its thickness or by surface printing, at regular intervals with no more than 6 inches (152 mm) of unmarked space between cable identification, with the following information: Manufacturer's Identificationor trade name Size of Conductor Conductor Material Type of Insulation Voltage Rating Nominal InsulationThickness Year of Manufacture
8.1.1
Optional Center Strand identification
When center strand identification is requested by the purchaser, the center strand of each conductor shall be indented w*Nithe manufacturets name and year of manufacture. This information shall be marked at regular intervals with no more than 12 inches (305 mm) between repetitions. 8.1.2
Optional Sequential Length Marking
When sequential length marking is requested by the purchaser, the information shall be marked at regular intervals of 2 feet (610 mrn) or 1 meter.
33
DATE: 7115/04
ICEA S-108-720-2004
Part 9 PRODUCTION TESTS 9.1 TESTING All cables shall undergo production tests at the factory to determine their compliance with the requirements given in Parts 2, 3, 4, 5, 6, and 7. When there is a conflict between the production test methods given in Part 9 and publications of other organizations to which reference is made, the requirements given in Part 9 shall apply. The tests in Part 9 may not be applicable to all materials or cables. To determine which tests are to be made, refer to the parts in this publication that set forth the requirements to be met by the particular material or cable.
9.2 SAMPLING FREQUENCY Sampling frequency shall be as indicated in Table 9-3 “Summary of Production Tests and Sampling Frequency Requirements”.
9.3 CONDUCTOR TEST METHODS 9.3.1
Method for DC Resistance Determination
Measurements shall be made on each chipping length. Except as noted above, this test shall be performed in accordance with ICEAT-27-581NEMA WC-53. 9.3.2
CroscSectionalArea Determination
Cross-Sectional area shall be determined in accordance with ICEA T-27-581/NEMA WC-53. 9.3.3
Diameter Determination
Diameter shall be determined in accordance with ICEA T-27-58VNEMA WC-53.
9.4TEST SAMPLES AND SPECIMENS FOR PHYSICAL AND AGING TESTS 9.4.1
General
Physical and aging tests shall be those required by Parts 3,4, 5, and 7. 9.4.2
Measurement of Thickness
The measurement of thickness for components having no minimum removability tension requirements shall be made with either a micrometer or an optical measuring device. For all other extruded components, the measurement of thickness shall be made only with an optical measuring device. The micrometer and optical measuring device shall be capable of making measurements accurate to at least 0.001 inch (0.025 mm). The nominal thickness of the insulation shall be taken as one-fourth of the sum of four measurements made around the circumference of the same cable cross section. One of the four measurements shall be at the minimum thickness point and one shall be at the maximum thickness point. Two additional measurements shall be made half way between the minimum and maximum measurements around the sample circumference.
34
DATE: 711WO4
ICEA S-108-720-2004 9.4.2.1 Micrometer Measurements
When a micrometer measuring device is used, the component shall be removed and the minimum and maximum thickness determined. 9.4.2.2 Optical Measuring Device Measurements When an optical measuring device is used, the minimum and maximum thickness shall be determined from a spechen cut perpendicular to the axis of the sample so as to expose the full cross-section. 9.4.3
Number of Test Specimens
From each of the samples selected, test specimens shall be prepared in accordance with Table 9-1.
Table 9-1 Test Specimens for Physical and Aging Tests Total Number of Test Specimens For determination of unaged properties Tensile strength and ultimate elongation
3t
Permanent set
3t
For accelerated aging te5ts
3t
For oil immersion
3t
Heat shock
1
Heat distortion
3t
Cold Elongation
3t
Stf¡RRin!l
1
tone test specimen out of three shall be tested and the other two specimens held in reserve, except that when only one sample is selected, then ali three test specimens shall be tested and the average of the resulis reported.
9.4.4
Size of Specimens
The test specimens shall be prepared using either ASTM D 412 Die B. E,C or D. Specimens from the insulation shall be cut rectangular in section with a cross-section not greater than 0.025 square inch (i 6 mm2). In extreme cases, it may be necessary to use a segmental spechen. Specimens for tests on jacket compounds shall be taken from the completed cable and cut parallel to the axis of the cable. The test specimen shall be a segment cut with a sharp knife or a shaped specimen cut out with a die and shall have a cross-sectional area not greater than 0.025 square inch (16 mm2) after irregularities, corrugations, and wires have been removed.
35
DATE 7/15/04
ICEA S-108-720-2004 9.4.5
Preparationof Specimens of Insulation and Jacket
The test specimen shall have no surface incisions and shall be as free as possible from other imperfections. Where necessary. surface irregulatities such as corrugations due to stranding shall be removed so that the test specimen will be smooth and of uniform thickness. If a jacket specimen passes the minimum requirement with irregularities, then their removal is not required. 9.4.6
Specimen for Aging Test
Specimens shall not be heated, immersed in water, nor subjected to any mechanical or chemical treatment not specifically described in this standard. 9.4.7
Calculation of Area of Test Specimens
9.4.7.1 Where the total cross-section of the insulation is used, the area shall be taken as the difference between the area of the circle whose diameter is the average outside diameter of the insulation and the area of the cirde whose diameter is the average outside diameter of the conductor shield. 9.4.7.2 Where a slice cut from the insulation by a knife held tangent to the wire is used and when the crosssection of the slice is a segment of a circle, the area shall be calculated as that of the segment of a circle whose diameter is that of the insulation. The height of the segment is the wall of insulation on the side from which the slice is taken. When the cross-section of the slice is not a segment of a circle, the area shall be calculated from a direct measurement of the volume or from the specific gravity and the weight of a known length of the specimen having a uniform crosssedon. The values may be obtained from a table giving the areas of segments of a unit cirde for the ratio of the height of the segment to the diameter of the circle. 9.4.7.3 When the conductor is large and the insulation thin and when a portion of a sector of a circle has to be taken, the area shall be calculated as the thickness times the width. This applies either to a straight test piece or to one stamped out with a die and assumes that corrugations have been removed. 9.4.7.4 When the conductor is large and the insulation thick and when a portion of a sector of a circle has to be taken, the area shall be calculated as the proportional part of the area of the total cross-section. 9.4.7.5 The dimensions of specimens to be aged shall be determined before the aging test. 9.4.8
Unageá Test Procedures
9.4.8.1 Test Temperature Physical tests shall be made at room temperature. temperature for not less than 30 minutes prior to the test.
The test specimens shall be kept at room
9.4.8.2 Type of Testing Machine The testing machine shall be in accordance with ASTM D 412. 9.4.8.3 Tensile Strength Test The tensile strength test shall be made with specimens prepared in accordance with 9.4.3 and 9.4.4. The length of all of the specimens for the test shall be equal. Gauge marks shall be 2 inches (50.8 mm)
36
ICEA S-I 08-720-2004
DATE: 7/15/04
apart when using ASTM B or E Die size and 1 inch (25.4 mm) apart when using ASTM C or D Die size except that 1 inch (25.4 mm) gauge marks shall be used for polyethylene regardless of the die size. Specimens shall be placed in the jaws of the testing machine with a maximum distance between jaws of 4 inches (101.6 mm) except 2.5 inches (63.5 mm) for polyethylene. The specimen shall be stretched at the rate of 20 inches (508 mm) per minute jaw speed until it breaks. The tensile and elongation determinations for cornpounds for which the compound manufacturer certifies that the baselesin content is more than 50 percent by weight of high densw polyethylene (having 3 density of 0.926 g/cm or greater), or total base polyethylene resin content (having a density of 0.926 9/cm or greater), shall be permitted to be tested at a jaw separation rate of 2 inches (51 mm) per minute as an alternate to 20 inches (508 mm) per minute. Specimens shall break between the gauge marks to be a valid test. The tensile strength shall be calculated based on the area of the unstretched specimen. Specimen length, gauge mark distance, and jaw speed shall be recorded with the results. 9.4.8.4 Elongation Test Elongation at rupture shall be determined simultaneously with the test for tensile strength and on the same specimen. The elongation shall be taken as the distance between gauge marks at rupture less the original gauge length of the test specimen. The percentage of elongation at rupture is the elongation in inches divided by the original gauge length and multiplied by 100. Specimen length, gauge mark distance, and jaw speed shall be reported with results. 9.4.9
Aging Tests
9.4.9.1 Aging Test Specimens Test specimens of similar size and shape shall be prepared from each sample selected, three for the determination of the initial or unaged properties, and three for each aging test required for the insulation or jacket being tested. Simultaneous aging of different compounds should be avoided. One specimen of each three shall be tested and the other two held as spares except that, where only one sample is selected, all three specimens shall be tested and the average of the results reported. Samples shall be cut from the insulation with a cross-section not greater than 0.025 square inch (16 mm2). D i e a t specimens shall be smoothed before being subjected to the accelerated aging tests wherever the thickness of the specimen will be 90 mils (2.29 mm) or greater before smoothing. The test specimens shall be suspended vertically in such a manner that they are not in contact with each other or with the side of the oven. The aged specimens shall have a rest period of not less than 16 hours nor more than 96 hours between the completion of the aging tests and the determination of physical propediec. Physical tests on both the aged and unaged specimens shall be made at approximately the same time. 9.4.9.2 Air Oven Test The test specimens shall be heated at the required temperature for the specified period in an oven having forced circulation of fresh air. The oven temperature shall be controlled to 11 OC. 9.4.9.3 Oil Immersion Test for Polyvinyl Chloride Jacket The test specimens shall be immersed in ASTM No. 2 or IRM 902 oil. described in ASTM D 471, at 70
OC11 OCfor 4 hours. At the end of this time, the specimens shall be removed from the oil, blotted to remove excess oil, and allowed to rest at room temperature for a period of 16 to 96 hours. The tensile strength and elongation of the specimens shall then be determined in accordance with 9.4.8 at the same time that the
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ICE3 S-108-720-2004 original properties are determined. 9.4.10
Hot Creep Test
The hot creep test shall be determined in accordance with ICEA Publication T-28-562. The sample shall be taken from the inner 25 percent of the insulation. 9.4.11
Solvent Extracfion
The solvent extraction shall be determined in accordance with ASTM 13 2765. 9.4.12
Wafer Boil Test for Conductor and Insulation Shields
Any outer covering and the conductor shalt be removed. A representative annular cross section containing the extruded conductor shield and insulation shield, shall be cut from the cable. The resuiting wafer shall be at least 25 mils (0.64 mm) thick. The wafer may be further separated into concentric rings by careful separation of the shield from the insulation. This may indude the use of a punch to separate the conductor shield or insulation shield from most of the insulation. The resulting wafer@)or rings shall then be immersed in boiling decahydronaphthalene with 1 percent by weight Antioxidant 2246 (or other reagents specified in ASTM D 2765, such as xyiene) for 5 hours using the equipment specified in ASTM D 2765. (This solution may be reused for subsequent tests provided that it works as effectively as a fresh solution). The wafer(s) shall then be removed from the solvent and examined for shieldlinsulation interface continuity with a minimum 15-power magnification. Total or partial separation of the semiconducting shields from the insulation is permissible. Partial loss of the shields is also permissible provided each shield is a continuous ring. If the conductor shield dissolves or cracks such that it does not maintain a continuous ring, the cable lot shall be rejected. If the insulation shield dicsolves or cracks such that it does not maintain a continuous ring, the cable lot shall either be rejected by the manufacturer or a sample of insulation shield from the same lot shall be subjected to the requirements of 9.4.12.1 as a referee test. 9.4.12.1 Insulation Shield Hot Creep Properties Hot creep and set properties shall be determined at 150 OC+2 OCin accordance with ICEA T-28-562 with the sample removed from the cable core. The degree of crosslinking shall be adequate to limit elongation to a maximum of 100 percent and set to a maximum of 5 percent. 9.4.13
Amber, Agglomerate, Gel, Contaminant, Protrusion, Irregularity and Void Test
9.4.13.1 Sample Preparation Samples shall be prepared by cutting a suitable length of cable helically or in some other convenient manner to produce 20 consecutive thin wafers consisting of the conductor shield, insulation and insulation shield. Wafers shall be approximately 25 mils (0.64 mm) thick. The cutting blade shall be sharp and shall produce wafers with uniform thickness and with very smooth surfaces. The sample shall be kept clean and shall be handled carefully to prevent surface damage and contamination. 9.4.13.2Examination The wafers shall be examined with 15 power magnification for voids, contaminants, gels, agglomerates, and ambers, as applicable, in the insulation. They shall also be examined for voids and protrusions between the insulation and the conductor and insulation shields and conductor shield imegularities. Unfilled insulations shall be examined using transmitied light. An optical coupling agent such as mineral oil, glycerin or silicone oil shall be used to enhance the observation of imperfections within the wafers. For EPR and
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ICEA S-108-720-2004
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extruded shields, a reflected light method shall be used. For void count, as applicable, the volume of the insulation examined shall be calculated using any convenient technique. The results of this examination . shall be recorded as pass or fail in the production test report. 9.4.13.3 Resampling for Amber, Agglomerate, Gei, Contaminant, Protrusion, Irregularity and Void Test If after examination according to 9.4.13.2, the size and/or number (as applicable) of voids, contaminants, agglomerates, gels, ambers, irregularities or protrusions exceeds the specified limits, the lot shall be divided into shipping lengths. One sample shall be taken from the beginning and end of each shipping length. For the shipping length to pass, both samples shall meet the requirements of this section. If either of the two samples from the shipping length fails, the shipping length shall be rejected. 9.4.13.4Protrusion and Irregularity Measurement Procedure
To measure the size of protrusions and conductor shield irregularities in wafers examined in 9.4.13.2, the wafers shall be viewed in an optical comparator or similar device which displays the wafer so that a straight edge can be used to facilitate the measurement. Protrusion shall be measured as shown in Figure 9-1. Conductor shield irregularities shall be measured as shown in Figure 9-2. This procedure is used on cable wafers with the conductor, jacket and metallic shield removed. Figure 9-1 Procedure to Measure Protrusions
Protrusion of
Figure 9-2 Procedure to Measure Irregularities
-/
39
Convolutions
DATE 7115/04
ICEA S-108-720-2004 9.4.14 Physical Tests for Semiconducting Material Intended for Extrusion 9.4.14.1 Test Sample
One test sample shall be molded from each lot of semiconducting material intended for extrusion on the cable. 9.4.14.2Test Specimens For each test, three test specimens, each approximately 6 inches (152 mm) long and not greater than 0.025 square inch (16 mm2) in crosssedion, shall be cut out of the test sample with a die. All three test specimens shall be tested and the results averaged. 9.4.1 4.3 Elongation This test shall be conducted in accordance with 9.4.8 and 9.4.9. 9.4.15 Retests for Physical and Aging Properties and Thickness If any test specimen fails to meet the requirements of any test, either before or after aging, that test shall be repeated on two additional specimens taken from the same sample. Failure of either of the additional specimens shall indicate failure of the sample to conform to this standard. If the thickness of the insulation or of the jacket of any reel is found to be less than the specified value, that reel shall be considered as not conforming to this standard, and a thickness measurement on each of the remaining reels shall be made. When ten or more samples are selected from any single lot, all reels shall be considered as not conforming to this standard if more than I O percent of the samples fail to meet the requirementsfor physical and aging properties and thickness. If 10 percent or less fail, each reel shall be tested and shall be judged upon the results of such individual tests. Where the number of samples selected in any single lot is less than ten, all reels shall be considered as not conforming to this standard if more than 20 percent of the samples fail. If 20 percent or less fail, each reel, or length shall be tested and shall be judged upon the results of such individual tests.
9.5 DIMENSIONAL MEASUREMENTS OF THE METALLIC SHIELD 9.5.1
Tape Shield
Metallic shielding tape shall be removed from no less than 6 inches (152 mm) of the insulated conductor, exœpt for corrugated tape shields where measurements shall be made on tape prior to corrugating and application to cable core. Measurements shall be made with a micrometer readable to at least 0.0001 inch (0.002 mm) having a presser foot 0.25 inch (6.35 mm) i 0.01 inch in diameter and exerting a total force of 3.0 I0.1 ounces (85 f 3 grams), the load being applied by means of a weight. Five readings shall be taken at different points on the sample, and the average of these readings shall be taken as the thickness of the tape. 9.5.2
Wire Shield
Metallic shielding wire shall be removed from no less than 6 inches (152 mm) of the insulated conductor. Measurements shall be made with a micrometer or other suitable instrument readable to at least 0.0001 inch (0.002 mm). The wires shall be measured at each end of the sample and near the middle of the sample. The average of the three measurements shall be taken as the diameter.
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ICEA S-I 08-720-2004 9.5.3
Sheath
The thickness of the sheath shall be determined by measurements made with a micrometer caliper having a rounded anvil or an optical measuring device. The micrometer and optical measuring device shall be capable of making measurements accurate to at least 0.001 inch (0.025 mm). The measurements shall be made directly on the sheath removed from the cable. 9.5.4
Flat Straps
Metallic shielding strap shall be removed from no less than 6 indies (152 mm) of the insulated conductor. Measurements shall be made with a micrometer or other suitable instrument readable to at least 0.0001 inch (0.002 mm). The straps shall be measured for width and thickness at each end of the sample and near the middle of the sample. The average of the three measurements for each dimension shall be taken as the width and thickness.
9.6 DIAMETER MEASUREMENTOF INSULATIONAND INSULATION SHIELD Measurement of the diameter over the insulation and the insulation shield shall be made with a diameter tape accurate to 0.01 inches (0.25 mm). When there are questions regarding compliance to this standard, measurements shall be made with an optical measuring device or with calipers with a resolution of 0.0005 inch (0.01 3 mm) and accurate to 0.001 inch (0.025 mm). At any given cross-section, the maximum diameter, minimum diameter, and two additional diameters which bisect the two angles formed by the maximum and minimum diameters shall be measured. The diameter for the cross-section shall be the average of the four values. This average diameter value shall be used to determine if the cable meets the minimum and maximum limits given in Appendix C. Ail diameter measurements shall be made on cable samples that contain the conductor.
9.7 TESTS FOR JACKETS 9.7.1
Heat Shock
9.7.1.1 Preparation of Test Specimen For jackets with a wall thickness not exceeding 200 mils (5.0 mm), each test specimen shall consist of a strip taken from the jacket, whose width shall be at least I.5times its thickness but not less than 160 mils (4.0 mm); the strip shall be cut in the direction of the axis of the cable. For jackets with a wall thickness exceeding 200 mils (5.0 mm), each test specimen shall consist of a strip taken from the jacket, whose width shall be at least 1.5 times its thickness but not less than 160 mils (4.0 rnm) and then ground or cut (avoiding heating) on the outer surface, to a thickness beheen 160 mils (4.0 mm) and 200 mils (5.0 mm). This thickness shall be measured on the thicker part of the strip, whose width shall be at least 1.5 times the thickness. 9.7.1.2 Winding of the Test Specimen on Mandrels Each test specimen shall be tightly wound and fixed at ambient temperature on a mandrel to form a close helix. The diameter of the mandrel and the number of tums are given in Table 9-2.
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ICEA S-108-720-2004
DATE: 7/15/04 Table 9-2 Bending Requirementsfor Heat Shock Test
Thickness of Test Specimen
I
Number of
Diameter of Mandrel
Inches
mm
Adjacent Turns
Inches (mm)
O - 0.039
0-1
6
0.079 (2)
0.040 - 0.079
1.01 - 2
6
O. 157 í4ì
0.080 - 0.118
2.03 - 3
6
0.236 (6)
0.119 - 0.157
3.02 - 4
4
0.31 5 (8)
o. 158 - 0.200
4.01 - 5
2
0.394 (10)
9.7.1.3 Heating and Examination Each test specimen, on its mandrel, shall be placed in an air oven preheated to a temperature of 121
OC+OC. I The test specimen shall be maintained at the specified temperature for Ihour. At the end of the test period, the sample shall be examined without magnification. 9.7.2
Heat Distortion
Heat distortion testing shall be performed in accordance with ICEA T-27-581kJEMA WC-53. 9.7.3
Cold Elongation
9.7.3.1 Test Temperature Physical tests shall be made at -35 "C.Test samples shall be conditioned at the test temperature for 1 hour prior to performing the tensile pull. 9.7.3.2 Type of Testing Machine The testing machine shall be in accordance with ASTM D 412 and equipped with a cooling device or installed in a cooling chamber. The test area (grips, chamber, extensometer) shall be conditioned at the test temperature for a minimum of 3 hours to ensure stability of the test environment. As an aitemate. the samples may be removed from a cold chamber and tested within 15 seconds on a testing machine at room temperature. 9.7.3.3 ElongationTest The number of elongation specimens shall be in accordance with 9.4.3. The length of all of the specimens for the test shall be equal. The test specimens shall be prepared using an ASTM D 412 Die D and the gauge marks shall be 1 inch (25.4 mm)apart. Specimens shall be taken from the completed cable and cut parallel to the axis of the cable. The test specimen shall be a segment cut with a sharp knife or a shaped specimen cut out with a die. The wall thickness of the specimen after irregularities, comgations, and wires have been removed shall not exceed 80 mils (2.0 mm) and not less than 30 mils (0.76 mm). Specimens can be ground or cut to meet thickness requirements. Specimens shall be left at ambient temperature after cutting or grinding for at least 16 hours before die cutting. Specimens shall be placed in the jaws of the testing machine with a maximum distance between jaws of 4 inches (101.6 mm) except 2.5 inches (63.5 rnm) for polyethylene. The specimen shall be stretched at the
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ICEA S-108-720-2004
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rate of 2 inches (51 mm) per minute jaw speed until it breaks. Specimens shall break between the gauge marks to be a valid test. The elongation shall be taken as the distance between gauge marks at rupture less the original gauge length of the test specimen. The percentage of elongation at rupture is the elongation in inches divided by the original gauge length and multiplied by 100. Specimen length, gauge mark distance, elongation measurement system, and jaw speed shall be reported with results.
9.8VOLUME RESISTIVITY 9.8.1
Conductor Shield
The samples shall be cut in half longitudinally and the conductor removed. Four silver-painted electrodes shall be applied to the conductor shield. The two potential electrodes (inner) shall be at least 2 inches (50.8mm) apart. A current electrode shall be placed at least 1 inch (25.4 mm) beyond each potential electrode. When a high degree of accuracy is not required, this test may be made with only two electrodes spaced at least 2 inches (50.8 mm) apart. The volume resistivity shall be calculated as follows:
p=
R ( D 2- d 2 ) IOOL
Where: p =Volume resistivity in ohm-meters. R = Measured resistance in ohms. D = Diameter over the conductor stress control layer in inches. d = Diameter over the conductor in inches. L = Distance between potential electrodes in inches. 9.8.2
Insulation Shield and Semiconducting Extruded Jacket Coating
Four annular-ring electrodes shall be applied to the surface of the insulation shield layer or extruded jacket coating. The two potential electrodes (inner) shall be at least 2 inches (50.8 mm) apart. A current electrode shall be placed at least 1 inch (25.4 mm) beyond each potential electrode. When a high degree of accuracy is not required, this test may be made with only two electrodes spaced at least 2 inches (50.8mm) apart. The volume resistivity shall be calculated as follows:
2R ( D 2- d 2 ) p=
IOOL
Where: p = Volume resistivity in ohm-meters. R = Measured resistance in ohms. D = Diameter over the insulation shield or semiconducting extruded jacket coating layer in inches. d = Diameter over the insulation or over the nonconductingjacket in inches. L = Distance between potential electrodes in inches. 9.8.3
Test Equipment
A suitable instrument (e.g., Wheatstone, Kelvin Bridge or Ohmmeter) or instruments (e.g., voltmeter and
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ICEA S-108-720-2004
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ammeter) shall be utilized for determining resistance and provide a source of 60 Hz ac or dc voltage. The energy released in the conducting component shall not exceed 100 milli-watts. A convection-type forceddraft, circulating air oven, shall be utilized capable of maintaining any constant (+ 1 OC)temperature up to 140 OC,e.g., Hot Pack Model 1204-14, Blue M Model OV-490, or Precision Type A 9.8.4
Test Procedure
For the fourelectrode method, connect the two outer electrodes (current) in series with the current source and an ammeter or the current leads of a bridge. Connect the two inner electrodes (potential) to potentiometer leads of a bridge or to a voltmeter. A dc or 60 Hz ac source can be used. For the twoelectrode method, connect the electrodes to an ohmmeter. The resistance of the conducting component between the electrodes shall be determined at the specified temperature.
9.9 SHRINKBACK TEST PROCEDURE 9.9.1
Sample Preparation
Five samples, each I.5feet (0.45 m) are required for the test. A length of the specimen cable 17.5 feet (5.25 m) long shall be laid out and straightened. The sample shall be marked at a point 5.0 feet (1.5 m) from one end and then marked at 1.5 foot (0.45 m) intervals for a distance of 7.5 feet (2.25 m). The cable shall be cut using a fine tooth saw at the 1.5 foot (0.45 m) intervals marked on the sample. The two 5.0 foot (1.5 m) end pieces from the original cable length are to be discarded. 9.9.2
Test Procedure
The five 1.5 foot (0.45 m) long cable samples shall be placed in a forced air convection oven at a temperature of 50 OCFIOCfor a period of 2 hourc. After the 2 hour period, the samples shall be removed from the oven and allowed to cool for 2 hours at room temperature. The heating and cooling cyde shall be performed three times, if required. At the end of each cooling period, the samples shall be measured for shrinkback using a micrometer, or preferably an optical measuring device. The selected measuring device shall have a minimum resolution of 0.001 inch (0.025 mm). One reading shall be made from each end of ea& sample between the end of the conductor and the edge of the conductor shield interface at the point of circumference of the conductor where shrinkback is maximum. 9.9.3
PasslFail Criteria and Procedure
The measured values shall be in accordance with Tables 4-8 of Part 4. Only the sample with the most shrinkback of the five shall be considered using the total shrinkback of both ends.
9-10 RETESTS ON SAMPLES Except for physical and aging properties and thickness tests
See 9.4.1 5
Except for Amber, Agglomerate, Gei, Contaminant, Protrusion, Irregularity and Void Test
See 9.4.13.3
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If all of the samples pass the applicable tests described in 9.4 through 9.9 and 9.13, the lot of cable that they represent shall be considered as meeting the requirements of this standard. If any sample fails to pass these tests, the length of cable from which the sample was taken shall be considered as not meeting the requirements of this standard and another sample shall be taken from each of the two other lengths of the cable in the lot of cable under test. If either of the second samples fails to pass the test, the lot of cable shall be considered as not meeting the requirements of this standard. If both such second samples pass the test, the lot of cable (except the length represented by the first sample), shall be considered as meeting the requirements of this standard. Failure of any sample shall not predude resampling and retesting the length of cable from which the original sample was taken.
9.11 AC VOLTAGE TEST 9.11.1 General These tests consist of voltage tests on each shipping length of cable. The voltage shall be applied between the conductor and the metallic shield with the metallic shield grounded. The rate of increase from the initially applied voltage to the specified test voltage shall be approximately uniform and shall be not more than 100 percent in 10 seconds nor less than 100 percent in 60 seconds. 9.11.2 AC Voltage Test This test shall be made with an alternating potential from a transformer and generator of ample capacity but in no case less than 5 kVA. The frequency of the test voltage shall be nominally between 49 and 61 Hz and shall have a wave shape approximating a sine wave as closely as possible. The initially applied ac test voltage shall be not greater than the rated ac voltage of the cable under test.
9.12
PARTIAL-DISCHARGE TEST PROCEDURE
Partialdischarge test shall be performed in accordance with ICEA Publication T-24-380. The manufacturer shall wait a minimum of 20 days after the insulation extrusion process before the tests are performed. The 20 day waiting period may be reduced by mutual agreement between the purchaser and manufacturer when effective degassing procedures are used.
9.13
METHOD FOR DETERMINING DIELECTRIC CONSTANT AND DIELECTRIC STRENGTH OF EXTRUDED NONCONDUCTING POLYMERIC STRESS CONTROL LAYERS
Determination of dielectric constant and dielectric strength shall be performed in accordance with ICEA T-27-58 IMEMA WC-53.
9.14
WATER CONTENT
Each end of each shipping length shall be examined for water under the jacket (if the cable is jacketed) and for water in the conductor (if cable does not have a sealant and is stranded).
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DATE: 7/15/û4
ICEA S-108-720-2004 9.14.1 Water Under the Jacket
If the cable is jacketed, 6 inches (152 rnm) of the jacket shall be removed and the area under the jacket shall be visually examined for the presence of water. If water is present, or there is an indication that it was in contact with water, effective steps shall be taken to assure that the water is removed or that the length of cable containing water under the jacket is discarded. 9.14.2 Water in the Conductor If the cable has an unsealed, stranded conductor, 6 inches (152 mm) of the conductor shall be exposed on each end. The strands shall be individually separated and visually examined. If water is present, the conductor shall be subjected to 9.14.4. 9.14.3 Water Expulsion Procedure
A suitable method of expelling water from the strands shall be used until the cable passes the Presence of Water Test. As soon as possible after the procedure. both ends of the cable shall be sealed to prevent the ingress of water during shipment and storage. 9.14.4 Presence of Water Test
To venb the presence of water in the conductor, the following steps shall be taken. Each length of cable to be tested shall be sealed at one end over the insulation shield using a rubber cap filled with anhydrous calcium sulphate granules. The tubber cap shall be ñtted with a valve. Dry nitrogen gas or dry air shall be applied at the other end until the pressure is 15 psi (100 kPa) gauge. The valve on the rubber cap shall then be opened sufficiently to hear a flow of gas. After 15 minutes, a check of the change of color of the granules in the rubber cap shall be made. If the color has not completely changed to pink after 15 minutes, it is an indication that a tolerable amount of moisture is present in the strands. In the case of complete change in color of all granules, the water shall be expelled from the conductor per 9.14.3. This procedure shall be repeated after placing new granules in the cap.
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ICEA S-108-720-2004
9.15
PRODUCTION TEST SAMPLING PLANS Table 9-3 Summary of Production Tests and Sampling Frequency Requirements STANDARD REFERENCE
TEST MEFHOD
REFERENCE
MINIMUM FREQUENCY
dc Resistance
Pari 2
9.3.1 and ICEAT-27581
100%
Diameter
Pari2
ICEA T-27-581
Plan A
Pari 2
ASTM
Manwrer certificabion that required values are met
ElongationAfter Aging
Part 3
9.4.14
Plan H
Volume ReSküvity
Pari 3
9.8.1
Plan H
Thicknecc
Pari 3
9.4.2
Plan E
Voids, Protrusionsand Inegulanties
Pari 3
9.4.13
Plan A
Wafer Boil
Pari 3
9.4.12
Plan B
pari
ICEA T-27-581
100%
Unagedand Aged Tensile and Elongation
Pari 4
9.4.8 and 9.4.9
Plan C
Hot Creep
Part 4
ICEA T-28-562
Plan B
Voids and Contaminants
Palt4
9.4.13
PlanA
Diameter
ADDendiDc c
9.6
Plan A
Shrinkback Test ( W E Only)
Pari4
9.9
Plan C
T h i c k n e s s and Ecœniriaty
Pari 4
9.4.2
Plan E
ElongationAfter Aging
Pari 5
9.4.14
Plan H
Volume Resistivity
Pari 5
9.8.2
Plan H
Thickness
Pari 5
9.4.2
Plan E
Voids and Protrusions
Pari 5
9.4.13
PianA
Wafer Boil
Pari 5
9.4.12
Plan B
Diameter
Appendix C
9.6
PlanA
TEST Conductor
Temper
I NonMetallìc Conductor Shield
Spark Test ( N m d u c ö n g Layer M Y )
Il insuiation
~
.I NonMetallic InsulationShield
I
47
~~
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DATE: 7/15/04
ICEA S-108-720-2004
Table 9 3 Summary of Production Tests and Sampling Frequency Requirements (Continued) STANDARD REFERENCE
TEST MEíHOD REFERENCE
MINIMUM FREQUENCY
Part 6
9.5
Plan E
Unaged and Aged Tensile and Uongation
Part 7
9.4.8 and 9.4.9
Plan D
Thickness
Part7
9.4.2
Plan E
Meiallfc Shields Dimensional Measurements Jacùeîs
,
Other Tests Applicable to Jacket Supplied Heat Distortion
I
Part 7
I
ICEA T-27-581
I
Pian H
Part 7
9.7.1
Plan H
Cold Bend
Part 7
ICEA T-27-581
Plan F
Oil Immersion
Part 7
9.4.9.3
Plan H
Volume Resisüviíy
Part 7
9.8.2
Pian O
Heat S
W
Il 1
I
Electrical lests ac Whstand Test
Part 4
9.11
Plan G
Partial Dischame Test
Patt 4
ICEA T-24-380
Plan G
Jacket Spark or W&stand Test
Part 7
ICE4T-27-581
100%
Part 2
9.14
Plan G
Other Te& Moisturein Condudor
I 9.14
~~
Moisture Under Jacket
7
Plan A One sample from each end of a manufacturer's master length. One sample from the outer end of each length is sufficient if at least one sample is taken every 10,000 feet (3.000 m). Plan B Three samples shall be taken per cable core extruder run. The samples shall be taken near the beginning, near the middle and near the end of each extruder run. The middle sample shall be eliminated if the extruder run is to be shipped in one continuous length.
Plan C One test for each 50,000 feet (15,000 m)of cable or at least once per cable core extruder run.
48
DATE: 7/15/04
ICEA S-108-720-2004 Plan D One test for each 50,000 feet (15,000 m)or at least once per jacket extruder run.
Plan E Table 9-4 Pian E
Quantity of Shipping Lengths Per Extnider Run
Number of Tests
1-2
each shipping length
3-19
2
20 and greater
10% of shipping lengths (Fractions shall be rounded to the next higher integer value)
Plan F Table 9-5 Plan F Jacket Extruder Run Length-feet (meters)
Number of Samples
less than 1,000 (300)
O
1,000 to 25,000 (300 to 8,000)
I
each additional25,000 (8,000)
1
Plan G One test per shipping length. For multiple conductor assemblies, each conductor of a shipping length shall be tested.
Plan H Each lot of material used for extrusion on the cable.
49
DATE: 7115104
ICEA S-108-720-2004
Part 10 QUALIFICATION TESTS 10.0
GENERAL
Qualification tests included in this standard are intended to demonstrate the adequacy of designs, manufacturing and materials to be used in high quality cable with the desired performance characteristics. It is intended that the product furnished under this standard shall consistently comply with all of the qualification test requirements. The tests are divided into three categories. The first is Cable Qualification. The second is Jacket Material Qualification. The third is ûther Qualification Tests. If requested by the purchaser, the manufacturer shall furnish the purchaser with a cerîified copy ofthe qualification tests that represent the cable being purchased. If a cable design was qualified in accordance with AEIC CS7-93 or AEIC CSô-96 specification, then it does not need to be requalified under this standard. Additional qualification tests in 10.2 and 10.3 are required to be performed, as applicable, in accordance with this standard.
10.1
CABLE QUALIFICATION TESTS
Qualification tests, as outlined in Flow Chart 10-1, shall be performed for each cable design. Samples with suitable conductor sizes (copper or aluminum) and designs shall be tested within a given voltage dass. The cable design passing qualification tests qualifies that voltage level and below, provided that the calculated electrical stresses at the conductor for the designs at lower voltage levels do not exceed the electrical stresses at the conductor calculated for the design selected for qualification purposes. Qualification of a cable design at one emergency operating temperature (105130 OC). qualifies all similar designs at the same or lower emergency operating temperatures. 10.1.1 Cable Design Qualification Qualification tests shall be performed for each manufacturing plant and for any changes of the compound compositions for the insulation, the conductor shield or the insulation shield. A qualified semiconducting conductor shield can be used as an insulation shield without requalification. Qualification tests consist of various electrical tests and conditioning procedures. Cable samples are conditioned by a Cable Bending Procedure (10.1.2) and a Thermal Cycling Procedure (10.1.3). Electrical Tests include a Hot Impulse Test (10.1.4) and an ac Voltage Withstand Test (10.15). Partial Discharge (10.1.6), and Dissipation Factor (lû.1.7) are also measured. A Sample Dissection and Analysis (10.1.8) is also performed in accordance with Flow Chart 10-1. Samples for the Impulse Test and the ac Voltage Withstand Test may be preconditioned as a single long length in the Cable Bending Procedure (10.1.2) and the Thermal Cycling Procedure (10.1.3). Additionally, the Resistance Stability Test 10.3.3 shall be performed on every shield material. The manufacturer has the option to perform all tests on one sample. In this case the Hot Impulse test shall be performed after the Dissipation Factor (10.1.7) is measured and before the Sample Dissection and Analysis (70.1.8) The Insulation Resistance Test 10.3.1 and Accelerated Water Absorption Test 10.3.2 shall be performed on each insulation material. The Discharge Resistance Test 10.3.5 shall be performed on EPR Class 1 intended for DischargeResistant designs. The Brittleness Tesî 10.3.4 shall be performed on every shield material. The results shall be on file with the manufacturer and are not required to be reported on the Cable Design Qualification Test report unless specifically requested.
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ICEA S-108-720-2004
If a cable design has been qualified, and the metallic shield or sheath, or the jacket generic type is changed while the cable core design, materials and manufacturing plant remains unchanged, the cable may be requalified by completing the Cable Bending Procedure (10.1.2) the Thermal Cycling Procedure (10.1.3) and the Sample Dissection and Analysis (10.1.8). The generic metallic shield, sheath or jacket types are specified in Table 10-1. Tests on the identical maten'als or design are not necessary to demonstrate the desired performance results. For jacket design changes only, the voltage during heat cycle (10.1.3.1) is not required. Table 10-1 Generic Groupings of Cable Components Metallic Shield and Sheaths
Longiîudinally Applied and Overlapped Comgated Tape
wire
Fiat Strap Lead Sheath
In
Smooth Aluminum Sheath Continuously Corrugated Sheath
Nonconducting Jackets:
b)
Low, medium and linear low density polyethylene
c)
High density polyethylene
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DATE: 7/15/04
ICEA S-108-720-2004
FLOW CHART 10-1 QUALIFICATION TESTS
TWO SAMPLES
I I
I
I
I
ONE SAMPLE
u
TBST
PERFORM DISSECTION (l.O+l, 8 )
52
ICEA S-108-720-2004 10.1.2
DATE: 7/15/04
Cable Bending Procedure
The cable sample(s) shall be bent around a cylindrical fixture at least one complete turn (360'). The cable shall be unwound and the bend repeated in the opposite direction. The sample(s) shall be bent at room temperature. A total of three bending cycles (three forward bends and three reverse bends) are required. The portion of the cable that is to be used for terminations need not be bent. 10.1.2.1 Bending Diameter
The cylindrical bending Mure shall have a diameter of:
1. 36(d+D) + 5% for cable designs with non bonded smooth aluminum sheaths or, 2. 25(d+D) + 5% for cable designs with lead, corngated sheaths, bonded smooth aluminum sheaths or longitudinally applied bonded metallic foil laminates (overlapped or welded) or,
3. 20(d+D) + 5% for all other designs. Where: d is the diameter of the conductor and D is the overall diameter of the compiete cable. 10.1.3 Thermal Cycling Procedure
After the Cable Bending Procedure (10.1.2), the sample(s) shall be installed in a pipe with a "u"bend (180' bend) sized so that when the cable is lying on the bottom surface of the pipe, there will be approximately 2 inches (51mm) of clearance between the top surface of the cable and the inner surface of the pipe. The "U" bend shall be located near the midpoint of the pipe. The diameter of the "U" bend is specified in 10.1.2.1 of the Cable Bending Procedure. Alternately, the cable may be wrapped with insulating material provided that the cable is formed into a loop with a "U" bend as described above. If thermal insulation is used, the "U" bend must be supported during this test. The sample shall be heated by circulation of current so that the conductor is at the designated emergency operating temperature for the cable design being tested. The temperature profile, as required in 10.1.3.1, shall be reported as part of the test report. If thermai insulation material is used, it shall have a uniform thermal resistance along the cable length. It shall also yield a temperature gradient across the cable that is within five degrees of the temperature gradient, which would be obtained by placing the cable in a plastic pipe. The thermal gradient is defined as the temperature difference between the conductor and the outside surface of the cable jacket. To insure that the thermal insulation and the plastic pipe yield a similar temperature gradient, it may be necessary to set up a "dummy" length of cable using a pipe and thermal insulation material to compare the thermal characteristics of each. 10.1.3.1 Thermal Cycles The thermal cycling shall be as follows: 1. Heating shall be applied for a minimum of 8 hours.
2. The conductor shall be maintained at the specified temperature for the last two hours of the heating period.
3. The heating period shall be followed by a cooling period of not less than 16 hours at room temperature. 4. Twenty (20) complete heating and cooling cycles shall be completed.
53
ICEA S-108-720-2004
DA=.
7115/04
10.1.3.2Voltage During Thermal Cycles During the thermal cycling described in 10.1.3.1, the sample(s)shall be energized at 2.0 V.,
10.1.4 Hot Impulse Test Procedure
A hot impulse test shall be made in accordance with IEEE Standard No. 82, "Test Procedure for Impulse Voltage Tests on Insulated Conductors," on one of the preconditioned samples of cable as shown in Flow Chart. The cable sample shall have a minimum active length is 30 feet (9.2 m). Hot impulse tests shall be made with the sample placed in a 15 foot (4.5 rn) long polyethylene or PVC conduit. The conduit diameter shall be such that when the cabie is lying on the bottom of the conduit, there shall be a clearance of approximately 2 inches (51 mm) between the top of the cable and the inner surface of the conduit. For hot impulse tests, the temperature of the conductor shall be equal to the rated emergency overload temperature of the cable +O/-5 OC. The temperature shall be achieved by circulating current in the conductor. The temperature at which the cables are qualified shall be reported. Ten impulses of each polarity with magnitude equal to the BIL shown in Table 4-6 shall be applied. The voltage shall then be raised over the BIL values listed in steps of approximately 10% of BIL with three impulses of negative polarity applied at each step and continuing to cable breakdown outside the terminals. The test may be discontinued when the limits of the test equipment are reached provided that the sample has passed the BIL value specified in Table 4-6. If the test has been discontinued without a cable breakdown, the sample shall be subjected to an ac withstand test at 2.5 V, for a duration of 15 minutes. This test is conducted to verify that the cable has not failed on the last impulse. impulse breakdown sites shall be dissected and the results shall be recorded and reported in the qualification test report. 10.1.5 AC Voltage Withstand Test Procedure
The second preconditioned cable sample will be given an ac voltage test. The cable sample shall have a minimum active length of 30 feet (9.2 m). The sample, at room temperature, shall withstand an ac voltage of 2.5 V, for 2 hours. The voltage applied to the sample shall be of power frequency (4961 hz) and the waveform shall be substantially sinusoidal.
i0.1.6 Partial Discharge Test Procedure (For Díscharge-Free Designs Only) After completion of the ac Voltage Withstand Test, the cable sample shall pass a partial discharge test as described in 4.3.2.1 of this standard except that the upper limit of the applied voltage shall be limited to 2.0 V,. The cable sample may be re-terminated for this test. 10.1.7 Measurement of DissipationFactor After completion of the partial discharge test, the sample shall have the dissipation factor measured. The sample shall be heated by circulating current to the specified emergency operation temperature +O/-5 OCin an enclosed conduit. The diameter of the conduit shall be as outlined in 10.1.4. Alternately, the sample may be wrapped in thermal insulation material. The dissipation factor shall be measured at V, while the cable is at the temperature specified above. The dissipation factor shall meet the requirements of Part 4. 10.1.8 Dissection and Analysis of Test Specimens
A dissection of the cabie samples subjected to Tests 10.1.2, 10.1.3 and 10.1.5 through 10.1.7 shall be made upon completion of the testing. The findings of the dissection, including a comparison with an unaged cable specimen of the same cable design shall be included with the qualification test data for information only.
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ICEA S-108-720-2004
10.2 JACKET MATERIAL QUALIFICATION TESTS The following qualification tests are for specific types of jacketing materials and shall be performed on each compound. The jacket material tests or certificationfrom the material supplier can be used by all cable producers who propose to use the material. The material qualification is valid until the compound is changed. 10.2.1 Polyethylene Jackets 10,2.1.1 Environmental Stress Cracking Test
Except as otherwise specified in 10.2.1.1.1 and 10.2.1.1.2, this test shall b e made in accordance with ASTM D 1693. 10.2.1.1.1 Test Specimen
Three test specimens approximately 1.5 inches (38.1 mm) long, 0.5 inch (12.7 mm) wide, and 0.125 inch (3.18 mm) thick from the sample shall be molded from matenal intended for extrusion. The temperature of the molded specimens shall be lowered at any suitable rate. A slit made with a razor blade, approximately 0.75 inch (19.0 mm) long and from 0.020 to 0.025 inch (0.51 to 0.64 mm) deep, shall be centrally located on one of the 1.5 inch by 0.5 inch (38.1 mm by 12.7 mm) surfaces. 10.2.1.1.2 Test Procedure
The specimens shall be bent with the slit on the outside and placed in a test tube 200 mm long and 32 mm in outside diameter. The cracking agent (Igepal C0-630, made by the GAF Corporation, or its equivalent) shall be added to completely cover the specimen. The test tube, suitably closed by means such as foil-covered cork, shall be placed in an oven at 50 OC+I OCfor 48 hours. At the end of this period, the specimens shall be removed, allowed to cool to room temperature, and inspected for cracking. 10.2.1.2Absorption Coefficient Test
The absorption coefficient of polyethylene jacket compound shall be determined in accordance with ASTM D 3349. Three test specimens shall be tested and the average of the results reported. 10.2.2 Semiconducting Extruded Jacket Coatings 102.2.1 Brittleness Temperature (See 10.3.4)
10.2.3 Polyvinyi Chloride i0.2.3.1 Sunlight Resistance
10.2.3.1.1 Test Samples
Five samples shall be prepared from material intended for extrusion or from completed cable. 10.2.3.1.2 Test Procedure
The test may be performed using either a carbon-arc or xenon-arc apparatus. For a carbon-arc apparatus, five samples shall be mounted vertically in the specimen drum of the carbon-arc-radiation and
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DATE 7115/04
ICEA S-lO8-720-2OO4
water-spray exposure equipment per ASTM G 153. For the xenon-arc apparatus, the samples shall be mounted, top and bottom, on a rack of the xenon-awadiation and water-spray exposure equipment per ASTM G 155. The test method shall also be in accordance with ASTM G 153 or ASTM G 155 respectively using Cycle 1 exposure conditions. The exposure time shall be 720 hours. Five die-cut specimens shall be prepared and tested for tensile and elongation from (1) unaged section of the cable jacket and (2) the conditioned samples, one specimen from each sample. The respective averages shall be calculated from the five tensile strength and elongation values obtained for the conditioned samples. These averages shall be divided by the equivalent averages of the five tensile and elongation values obtained for the unaged specimens. This provides the tensile and elongation ratios for the jacket. The jacket is not sunlight resistant if an 80 percent or greater retention for either the tensile or elongation after the 720 hours of exposure is not maintained.
10.3
OTHER QUALIFICATIONTESTS
10.3.1 Insulation Resistance Insulation resistance test shall be performed in accordance with ICEA T-27-581/NEMA WC-53. 10.3.2 Accelerated Water Absorption Tests Accelerated water absorption test shall be performed in accordance with ICEA T-27-581/NEMA WC-53. Cables intended for installation in dry locations or having a radial moisture banier in accordance with paragraph 6.4 do not have to meet the Accelerated Water Absorption Test. The insulation shall meet the following requirements: Table 10-2 Accelerated Water Absorption Properties Insulation Type
Accelerated Water Absorption Properties (Electrical Method)
XìPE
EPR Class I 8 II
Water ImmersionTemwrature. OC
75
75
Dielecîtic Constant afier 24 hours, maximurn
3.5
4.0
Increase in capacitance, maximum, percent Ito 14 days 7 to 14 davs
3.0 I.5
3.5
~
1.5 ~
1 Stability Factor after 14 days, maximum*
I
1 Alternate to Stability Factor - Stabiïi Factor
I
I
I
I difference, 1 to 14 davs. maximum*
I.o
I
0.5
Only one oí these Co requiremenisneed be saüsfied, not both.
10.3.3 Resistance Stability Test The requirements described in Parts 3 and 5 of this standard and in ICEA T-25425 shall be met.
56
I
I
I
DATE: 7115/04
KEA S-108-720-2004 10.3.4 Brittleness Temperature for Semiconducting Shields
This test shall be performed on a sample of the matenal(s) intended for extrusion in accordance with ASTM D 746 using a Type Ior IISpecimen. 10.3.5 Discharge Resistance Test for Discharge-Resistant EPR Designs Only Compound mixing qualification of the insulation used for discharge-resistant cable designs is required. Once per month a sample of each qualified insulation shall be obtained from each compound mixing line and subjected to this test The test shall be performed in accordance with ASTM D 2275 using the following standard specimens and conditions. 10.3.5.1 Test Specimens From each test sample, three test specimens, each having a minimum diameter Of 4 inches (101.6 mm) and a thickness of 0.060 inch +, 0.004 inch (15 2 mm f 0.10 mm), shall be molded and suitably cured. The prepared specimens shall be held for a minimum of 72 hours at room temperature followed by 16 hours minimum in the same environment as the electrical discharge test. 10.3.5.2Test Environment The discharge test shall be performed in an area provided with a controlleddraft flow of conditioned air to maintain the required relative humidity and temperature and with suitable venting to remove ozone and other gasses. 10.3.5.3Test Electrodes The electrodes shall be of stainless steel Type 309 or 310, with a surface finish of 16 pin (0.406 pm). Each upper electrode, to which the test voltage is applied, shall be a cylindrical rod having a diameter of 0.250 inch +- 0.010 inch (6.35 mm i 0.254 mm) and a length adjusted to provide a contact weight of 30 grams +- 3 grams when positioned vertically atop the center of the insulation specimen. The contacting end shall be flat except for edges rounded to a radius of 0.035 inch i 0.005 inch (0.89 mm H.127 mm). The lower electrode(s) shall be electrically grounded and may be either (1) a common plate under, and extending at least 2 inches (50.8 mm) beyond, the array of upper electrodes or (2) individual flat discs of 1.25 inch (31.75 mm) minimum diameter, centered under each upper electrode.
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DATE: 7/15/04
ICEA S-108-720-2004
Part 11 APPENDICES APPENDIX A NEMA, ICEA, IEEE, ASTM AND ANSI STANDARDS (Normative) A I NEMA PUBLICATIONSt WC 26/EEMAC 201 (2000)
BinationalWire and Cable Packaging
WC 5311CEA T-27-581 (2000)
Standard Test Methods for Extruded Dielectric Power, Control, Instrumentation & Portable Cables for Test
A2 ICEA PUBLICATIONSt P-32-382-1999
Short Circuit Characteristic of Insulated Cable
P-45482-1999
Short Circuit Performanceof Metallic Shields and Sheaths on Insulated Cable
T-24-380-1994
Guide for Partial-DischargeTest Procedure
T-254252003
Guide for Establishing Stahiity of Volume Resistivity for Conducting Polymeric Componentsof Power Cables
T-28-562-1995
Test Method for Measurement of Hot Creep of Polymeric Insulation
T-31-610-1994
Guide for Conducting a Longitudinal Water Penetration Resistance Test for Sealed Conductor
T-32-645.1993
Guide for Establishing Compatibility of Sealed Conductor Filler Compounds with Conductor Stress Control Materials
T-34-664-1996
Guide for Conducting Longitudinal Water Penetration Resistance Tests on LongitudinalWater Blocked Cables
A3 IEEE AND ANSI STANDARDS$ IEEE Std 82-2002
IEEE Standard Test Procedure for Impulse Voltage Tests on Insulated Conductors
IEEWANSI C2-2000
National Electrical Safety Code (NESC)
A4 ASTM STANDARDS* B 3-01
Soft or Annealed Copper Wire. Specification for
B 500
ToughPitch Electrolytic Copper Refinery Shapes, Specification for
B û-99
Concentric-Lay Stranded Copper Conductors, Hard, Medium-Hard, or Soft, Specificationfor
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ICEA S-108-720-2004 B 29-92
Refined Lead, Specification for
B 33-00
Tinned Soft or Annealed Copper Wire for Electrical Purposes, Specificationfor
B 193-02
Resistivity of Electrical Conductor Materials, Test Method for
B 230-99
Aluminum 1350-HI9 Wire, far Eledncal Purposes, Specification for
B 231-99
Concentric-Lay-StrandedAluminurn 1350 Conductors, Specification for
B 233-97
Aluminum 1350 Drawing Stock for Electrical Purposes, Specification for
B 400-01
Compact Round Concentric-Lay-Stranded Aluminum 1350 Conductors, Specification for
B 496-01
Compact Round ConcenirieLayStranded Copper Conductors, Specification for
B 609-99
Aluminum 1350 Round Wire, Annealed and Intermediate Tempers, for Electrical Purposes, Specification for
B 784-01
Modified Concentric-Lay-StrandedCopper Conductor for Use in Insulated Electrical Cables, Specification for
B 786-02
19 Wire Combination Unilay-Stranded Aluminum 1350 Conductors for Subsequent Insulation, Specification for
B 787-01
19 Wire Combination Unilay-Stranded Copper Conductors for Subsequent Insulation, Specification for
B 800-00
8000 Series Aluminurn Alloy wire for Electrical Purposes - Annealed and Intermediate Tempers, Specification for
B 801-99
Concentric-Lay-Stranded Conductors of 8000 Series Aluminum Alloy for Subsequent Covering or Insulation, Specification for
B 835-00
Compact Round SIW Stranded Copper Conductors, Specification for
B 836-00
Compact Round SIW Stranded Aluminum Conductors, Specification for
D 412-98
Vulcanized Rubber and Thermoplastic Rubbers and Thermoplastic Elastomers - Tension, Test Methods for
D 471-98
Rubber Properly - Effect of Liquids. Test for
D 746-98
Brittleness Temperature of Plastics and Elastomers by Impact, Test Method for
D 1693-01
Environmental Stress - Cracking of Ethylene Plastics, Test Method for
D 227501
Voltage Endurance of Solid Insulating Materials Subjected to Partial Discharges (Corona) on the Surface, Test Method For
D 276501
Determination of Gel Content and Swell Ratio of Crosslinked Ethyíene Plastics, Test Methods for
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ICEA S-108-720-2004
D 3349-99
Absorption Coefficient of Ethylene Polymer Material Pigmented with Carbon Black, Test Method for
D 4496-99
DC Resistance or Conductanceof Moderately Conductive Materials, Test Method for
G 153-00
Operating Enclosed Carbon Arc Light Apparatus for Exposure of Nonmetallic Materials, Practice for
G 15500
Operating Enclosed Xenon Arc Light Apparatus for Exposure of Nonmetallic Materials, Practice for
t
Copies may be obtained from Global Engineering Documents, 15 Inverness Way East, Englewood, CO 80112, USA.
$
Copies may be obtained from IEEE Service Center, 445 Hoes Lane, Piscataway, NJ 08854,USA. Copies may be obtained from the American Society for Testing and Materials, I00 Barr Harbor Drive, West Conshohocken, PA 19429-2959, USA.
60
ICEA 5-108-720-2004
DATE: 7/15/04
APPENDIX B EMERGENCY OVERLOADS (Normative) Operations at the emergency overload temperature shall not exceed 1500 hours cumulative during the lifetime of the cable. Overload temperatures are 105 to 130 OCfor cables rated up to and including 138 kV and 105 OCfor cables rated abwe 138 kV. STATEMENT ON EMERGENCY OPERATING TEMPERATURE The following discussion is intended to point out some of the factors which should be taken into consideration when operating extruded power cables at conductor temperatures in excess of 105 Oc. It is not intended to be a comprehensive discussion. The cable manufacturer should be contacted for specific details regarding the operation of cables at temperatures above 90 "C. Extensive tests sponsored by the Electric Power Research Institute (EPRI) have shown that conductive and insulating thermoset materials commonly used in the construction of extruded underground distribution power cables are capable of operating satisfactorily at 130°C or higher. However, some electric power utilities and testing facilities have determined from experience and from tests that the maximum conductor temperature of a composite power cable constructed with these materials may need to be less than 130°C which has been used in the past. This limitation is necessary because some metallic shield designs are known to cause operating problems when the cable core diameter is large. This problem is primarily the result of thermal expansion of the cable core which can be very significant at conductor temperatures as high as 130 "C.Some metallic shield designs and their effect on cable cores at elevated emergency operating temperatures are discussed below. Wire Shields Concentrically applied wire shields can imbed in the insulation shield when the cable core expands. Conductive, cloth-type bedding tapes over the insulation shield and carefully chosen lay factors can be employed to minimize this problem. Copper Tape Shields Helically applied copper tape shields may stretch and lose contact with the insulation shield. They can also wrinkle and crack. Properly chosen conductive, cloth-type semiconducting bedding tapes can be used to minimize this problem. Metallic Sheaths Lead sheaths have a tendency to stretch and lose contact with the insulation shield. Semiconducting bedding tapes over the insulation shield may be needed to minimize this problem. Cormgated or smooth aluminum or copper sheaths are also available. Flat Straps Shields Concentrically applied Rat strap shields can cause severe deformation of the cable core. They can also cause torsional forces which may damage the conductor. Flat strap shields are not recommended for XLPE cables that may operate at conductor temperatures near 130"C.
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ICEA S-108-720-2004
Longitudinally Folded Corrugated Copper Tape Shields Longitudinally folded corrugated copper iape shields are capable of expanding and contracting with the cable core with Iìffle or no adverse effects. Overall Jackets
Commonly used jacketing materials such as low density polyethylene (LDPE) and polyvinyl chloride (PVC) can become soft and deform when the cable conductor is operated at elevated temperatures. Cracking of LDPE jackets has also been observed. Careful jacket extrusion and cooling techniques or other jacket compounds may be useful altematives. Other Factors The metallic shield designs mentioned are often used in combination with each other. The ability of these combinations to withstand elevated emergency operating temperatures is very much a function of the specific combination employed. Joint and termination limitations, cable environmental conditions as well as metallic shield designs may require the use of lower emergency operating temperatures. Consideration of mechanical constraints of cabíe accessories and to the cable installation must be given when cables are to be operated at high temperatures. Summary In summary, the ability of a transmission cable system to withstand emergency temperatures is a complex function of all of the materials used in the cable design. In addition, there is a shortage of research and field experience for high voltage extruded insulation transmission cables operating for long periods at temperatures greater than 90°C. The information presented here is only intended to give the cable user a brief review of some of the variables that must be considered before operating a cable system at emergency temperatures above i05 OC.The cable manufacturer should be consulted for verification of the emergency operating temperature of a given cable design.
62
ICEA S-108-720-2004
DATE: 7/15/û4
APPENDIX C PROCEDURE FOR DETERMINING THICKNESS REQUIREMENTS OF THE INSULATION SHIELD, LEAD SHEATH AND JACKET (Normative) C I Insulation shield, lead sheath ( i applicable) and jacket thicknesses shall be determined by calculating diameters as follows. This procedure is not intended for determining cable diametee. Ail dimensions are in mils. Cl.1
The calculated diameter over the insulation shall be determined as follows:
D, = C + A , + 2 x C S + 2 x T Where:
DI = C = Al = CS =
T =
C1.2
Calculated diameter over insulation Applicable nominal conductor diameter from Part 2 (for segmental use smallest diameter) Semiconducting tape adder, if applicable (Manufacturerto determine) Minimum point extruded conductor shield thickness from Part 3 Nominal insulation thickness (Manufacturer to determine)
The calculated diameter under metallic shielding shall be determined as follows:
DA= D , + 8 0 + A 2 Where:
DA= DI = AZ = C l .3
Calculated diameter under metallic shielding Calculated diameter over insulation Semiconductingbedding layer diameter adder, if applicable (Manufacturer to determine)
The calculated diameter under jacket shall be determined as follows:
DB=DA+2xT,+A, Where: DB = DA=
TS =
Ag
=
Calculated diameter under jacket Calculated diameter under metallic shielding Metallic shield thickness (Manufacturer to determine - Minimum point thickness for lead and smooth aluminum sheath, wire diameter, cormgation height for corrugated sheaths and tape shields, flat strap thickness, equivalent thickness for helically applied tape shield or for combination shieldlsheaths the combined thickness) Bedding layer or separator tape diameter adder, if applicable (Manufacturer to determine)
Example: 1500 compact segmental conductor, conductor shield, 650 nominal insulation wall, insulation shield, bedding tape, lead sheath and a LLDPEjacket, 138 kV cable.
63
DATE 7/15/04
ICEA S-108-720-2004 Calculate calculated diameter over the insulation: C AI 2xcs 2xT DI
= 1375 mils = 48 mils (Manufacturer determined) = 48 mils (CS= 24 from Part 3) = l3QQ mils (T=650 Manufacturerdetermined) = 2771 mils
Determine insulation shield thickness requirements: Based on the calculated diameter over the insulation of 2.771 inches per Table 5-1 insulation shield thicknesses shall be 40 mils minimum point and 100 mils maximum point. Calculated diameter under metallic shielding:
DI Az
DA
= 2771 = 80 =
i28
= 2979
mils mils mils (Manufacturer determined) mils
Determine lead sheath thickness: Based on the calculated diameter over the insulation of 2.979 inches per Table 6-1 lead sheath thicknesses shall be 100 mils minimum point and 150 mils maximum point. Calculated diameter under jacket:
= 2979 = 200 = D = 3179
mils mils (Ts= 100from Part 6) mils (Manufacturer determined) mils
Determine lead sheath thickness: Based on the calculated diameter over the insulation of 3.179 inches per Table 7-5 jacket thicknesses shall be 100 mils minimum point and 150 mils maximum point.
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APPENDIX D CABLE COMPONENT FUNCTION (Informative)
D I CONDUCTOR D1.1 Function A wire or combination of wires designed for carrying an electric current. The current could be due to a normal load, emergency load or from a short-circuit condition. During installation, the conductor typically iS a mechanical load-bearing component of a cable. 01.2 Material Copper and aluminum are the two most commonly used conductor materials. At least the following propetties are to be considered when selecting the material of the conductor. Tensile Strength Conductivity Density Specific Heat Flexibility Elongation Coefficient of Expansion Corrosion resistance
D2 CONDUCTOR SHIELD D2.1
Function
A nonconducting or semiconducting element in direct contact with the conductor and in intimate contact with the inner surface of the insulation that acts as a stress control layer. D2.1.1 Nonconducting Its function is to provide uniform voltage stress at the inner surface of the insulating wall.
D2.1.2 Semiconducting Its function is to eliminate ionization at the conductor and provide uniform voltage stress at the inner surface of the insulating wall. The potential of this element is essentially the same as the conductor. D2.2
Voltage Stress
The voltage stress within a cable is highest at the conductor (or semiconducting conductor shield) according to the following equation:
V’ = Vg / ( Rx in($)) Where: Vs= Radial voltage stress in kV/mm V, = Voltage to ground in kV R = Distance from center of conductor in mm D = Diameter over the insulation d = Diameter over the conductor (or semiconducting conductor shield)
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"Since D and d only appear in the ratio Old, their units of measure do not matter as long as they are the same. From this equation, the radiai voltage stress increases as "f?" approaches "CUY with the voltage stress reaching Ws maximum when R = CV2 at the surface of the conductor or conductor shield. Decreasing the diameter "6of the conductor increases the radial voltage stresses. Without a smooth cylindrical conductor shield around a stranded conductor (see Figure 0-1). the voltage stresses would be concentrated around the individual conductor strands increasing the potential for insulation breakdown and future faults.
CONDUCTOR CONDUCTOR SHIELDING INSULATION IONIZATION
ConductorShielding
Figure D-1
D3 INSULATION The next layer of material on the cable is the insulation. It is relied upon to electrically insulate the conductor from other conductors or conducting parts or from ground. The insulation material must be capable of withstanding the electrical stresses that will be distributed across it when the conductor is energized. It also has to withstand the thermal and mechanical forces that occur during installation and operation of the cable.
D4 INSULATION SHIELD Insulation shields are applied over the insulation material. Insulation shields generally consist of a conductive non-metallic shield and a metallic shield. The purpose of an insulation shield is to confine the electric field within the insulation and to symmetncaliy distribute voltage stresses in the cable insulation. Cables without insulation shields have electric fields that extend partially within the insulation and whatever exists between the insulation and ground. If the field is sufficiently intense, it will cause the air near the cable to ionize and form corona (Figure û-h) which can damage the cable insulation or it can cause the insulation itself to break down. Nonuniformdistribution of the electric field causes increased radial stress in portions of the insulation (Figure D-2a). A shield applied over the insulation results in a symmetrically distributed radial stress, thus utilizing the insulation to its greatest efficiency (Figure D2b). The stress at the insulationlinsulaüon shield interface is an important parameter when selecting accessories. This stress can be calculated with the following formula.
G ,
= Vg /(Ri x In(%))
Where: Gdn = Voltage stress at the insulationlinsulation shield interface in kV/mm
V, = Voltage to ground in kV Ri= Radius over the insulation in mm Rs= Radius of the conductor shieldlinsulation interface in mm.
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Semiconducting Shield
Semiconducting elements applied directly over and in intimate contact with the outer surface of the insulation. When effectively grounded. its function is to confine the dielectric stress to the underlying insulation. Additionally, with discharge freedesigns, it eliminates ionization at the surface of the insulation. D4.2
Metallic Shield
A nonmagnetic, metallic material applied over the semiconducting shield. The purpose of the metallic shield is to serve as a current-canying medium for charging and leakage currents and to provide a solid ground plane. If the metallic shield is large enough, it can also be used to cany neutral currents, unbalanced phase currents and fault currents. The metallic shield can consist of wires, flat straps, tape, foils or a sheath.
NON-SHIELDED CABLE
CONDUCTOR
EVEN STRESS DISTRIBUTION HIGH STRESS CONCENTRATION
Figure D-2
D5 JACKETS The jacket is a covering that provides the functions listed in Table P1.The jacket can either be nonconducting or semiconducting.
Mechanical Protection
Jackets provide a certain amount of protection to the cable core from mechanical abuse such as abrasion, scoring and impact and sidewall bearing pressures that occur during handling and installation.
Chemical Protection
Jackets can provide protection from certain chemicals that might be detrimental to the cable core.
67
,onFiltratlon
Research has shown that many of the contaminants found in cable insulations have migrated into the cable from the surrounding soil. Jackets, though not typically designed for this, do filter out some of these ions as moisture migrates into the cable. As a general rule, the ability of the jacket to filter ions will increase as the thickness of the jacket wall increases.
Corrosion Resistance
Experience has shown that the metallic shields of un-jacketed cables will corrode in many types of coil. The application of a jacket can greatly reduce this corrosion.
Moisture Migration
Moisture penetration is a major conbibutor to the deterioration of cable insulation. Jackets can reduce the rate at which moisture migrates into the cable core.
L Electrical
The jacket sewes a very important electrical function in bonded cable systems such as single-point bonding and cross bonding. To work properly and avoid rapid corrosion phenomena, these bonding systems require that the metallic shield of the cable and joint are electrically isolated from earth ootential.
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APPENDIX E HANDLING AND INSTALLATION PARAMETERS (Informative)
E I INSTALLATION TEMPERATURES All cable manufactured to this standard can be safely handled if not subjected to temperatures lower than -10 OCin the twenty four hour period preceding installation. For installation during colder temperatures contact the cable manufacturer for cable suitability or recommendedpractices.
E2 RECOMMENDED MINIMUM BENDING RADIUS The limits shown in Table E-I may not be suitable for conduit bends, sheaves, or other curved surfaces around which the cable may be pulled under tension while being installed due to sidewall bearing pressure limits of the cable. The minimum radius specified refers to the inner radius of the cable bend and not to the axis of the cable. Table E4 RecommendedMinimum Bending Radius Shield or Sheath Type
Ratio of Bend Radius to Cable O.D.*
Helically Applied flat Tape
20
Longitudinally Applied Corrugated Tape
20
wires or Flat Straps Shields
18
Lead Sheath
18
Non Bonded Smooth Aluminum Sheath
40
Bonded Smooth Aluminum Sheath
20
Corrugated Sheath (copper or aluminum)
20
1
* For combination shields and/or sheaths use the highest ratio
E3 DRUM DIAMETERS OF REELS The manufacturer shall determine the minimum diameter of the drum of the reel. Information on reel construction and sizing may be found in NEMA Publication No. WC 26, Binational Wire and Cable Packaging.
E4 MAXIMUM TENSION AND SIDEWALL BEARING PRESSURES Consult the cable manufacturer for recommended maximum pulling tensions and maximum sidewall bearing pressures.
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E5 ELECTRICALTESTS AFTER INSTALLATION E5.1
Insulation
Tests on new installations are camed out when the installation of the cable and itc accessories has been completed. By agreement between the manufacturer and the purchaser, an ac voltage at a frequency between 20 Hz and 300 Hz, in accordance with one of the following may be used: E5.1.I Test for 1 hour with a voltage of 1.4 V, to 1.7 V, , depending on practical operational conditions. E5.1.2 Test for at least 24 hours with the normal operating voltage of the system. E5.2
Jacket
If a semiconducting coating is applied over the jacket, the jacket maybe tested with a dc voltage. A dc voltage of 150 V/mil (6 kV/mm) of the average value of the specified minimum point and maximum point thickness of the jacket with a maximum of 24 kV between the metallic shieldsheath and the semiconducting outer coating shall be applied for one minute.
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APPENDIX F TRADITIONAL INSULATION WALL THICKNESS (Informative) Table F-I Traditional InsulationThickness from AEIC CS7-93, Test Voltages and Conductor Sizes Rated Circuit
Conductor Size, (kcmil)
Sh, (mm?
69
500-2000
115
i 313
Voltage, Phase4oPhase Voltage
(kV)
Minimum Avenge Insulation Thickness
ac Test Voltage
15 Min. Test 3.0 Vg
30 Min. Test 2 5 Vg
Mils (mm)
(kv)
0
253-1013
650(16.2)
120
1O0
750-3000
380-1520
800 (20.3)
200
160
750-3000
380-1520
850 (21.6)
240
200
Notes on Table F-I: 1. Either the 15 minute or the 30 minute ac test is required. Ac test levels for the appropriate rated voltage are to be used as the basis for ac testing should insulation thickness other than those in Table F-I be utilized. All ac tests shall be conducted at room temperature and at power frequency (4461 Hz). The waveform shall be substantially sinusoidal. All ac voltages are mis values. 2. The actual operating voltage shall not exceed the rated circuit voltage by more than (a) 5 percent during continuous operation or @) 10 percent during emergencies lasüng not more than 15 minutes. 3. The cable insulation thickness specified is for application where the system is provided with circuit protection such that ground faults will be deared as rapidly as possible, but in any case within one minute. While these cables are applicable to installations which are on grounded systems, they may also be used on other cable systems, provided the above dearing requirements are met in completely de-energizing the faulted section. 4. For other voltage ratings and conductor sizes, specific agreement between purchaser and manufacturer in the selection of insulation thickness for each application is required. When the purchaser is considering conductor sizes or insulation wall thickness less than the values shown in Table F-I, the effects of maximum voltage stresses should be evaluated. 5. There may be unusual installations and/or operating conditions where mechanical considerations dictate the use of a larger insulation thickness. When such conditions are anticipated, the purchaser should consult with the cable supplier to determine the appropriate insulationthickness. 6. It is recommended that the minimum size conductor be in accordance with Table F-I . 7. AEIC CS7-93 did not include thicknesses for greater than 138 kV class cables. 8. A radial moisture barrier is optional on cables with traditional insulation wall thicknesses as shown in Table F-I.
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APPENDIX G ADDITIONAL SHIELD WIRE AND CONDUCTOR INFORMATION (Informative) Table G-1 Solid Comer Shield Wires Approximate Weight Conductor
Sue,
Copper
20
3.10
4.61
19
3.90
5.81
ia
4.92
7.32
17
6.21
9.24
16
7.81
11.6
15
9.87
14.7
14
12.4
18.5
13
15.7
23.4
12
19.8
29.4
11
24.9
37.1
10
31.43
46.77
9
39.62
58.95
a
49.98
74.38
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Table G-2 Concentric Stranded Class B Aluminum and Copper Conductors
Conductor Sue, AWG or kcmil 250
300 350 400 450 500
550 600 650 700 750
800 900 1000 1100 1200 1250 1300 1400 1500 1600 1700 1750 1800 1900 2000 2250 2500 2750 3Ooo 3250 3500 3750 4000
Number of Suands
37 37 37 37 37 37 61 61 61 61 61 61 61 61 91 91 91 91 91 91 127 127 127 127 127 127 127 127 169 169 169 169 217 217
Approximate Diameter of EachStrand mils
mm
822
2.09 2.29 2.47 264 2.80 2.95 2.41 2.52 2.62 2.72 2.82 2.91 3.09 3.25 2.79 2.92 2.98 3.04 3.15 326 2.85 2.94 2.98 3.02 3.11 3.19 3.38 3.56 3.24 3.38
90.0 97.3 104.0 110.3 116.2 95.0
992 103.2 107.1 110.9 114.5 121.5 128.0 109.9 114.8 117.2 119.5 124.0 128.4 112.2 115.7 117.4 119.1 122.3 125.5 133.1 140.3 127.6 133.2 138.7 143.9 131.5 135.8
Approximate WeigM Aluminum Pounds per 1000 Feet 235 282 329 376 422 469 517 563 610 657 704 751
845
3.52
939 1032 1126 1173 1220 1313 1408 1501 1596 1643 1691 1783 1877 2132 2369 2607 2841 3111
3.66 3.34 3.45
3348 3590 3829
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-pper
Slm 349 419 489 559 629 699 768 a38 908 978 1o50 1120 1260 1400 1540 1680 1750 1820 1960 21O0 240 2370 2440 251o 2650 2790 3170 3530 3880 4230 4630 4980
5340 5700
Pounds per 1O00 Feet
srm
772 925 1080 1236 1390 1542 1700 1850 2006 2160 2316 2469 2780 3086 3394 3703 3859 4012 4320 4632 4936 5249
1150 1380 1610 1840 2070 2300 2530 2760 2990 3220 3450 3680 4140 4590 5050 551o 5740 5970
5403 5562 5865 6176 7015 7794 8579 9349 10235 11017 11813 12598
6430 6890 7350 7810 8040 8270 8730 9190 10440 11600 12770 13910 15230 16400 17580 18750
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DATE 7115104
Table 63 Concentric Stranded Class C and D Aluminum and Copper Conductors Class c Conductor Size, AwG or kcmil
Number of Strands
250 300 350 400 450 500 550 600 650 700 750
61 61 61 61 61 61 91 91 91 91 91 91 91 91 127 127 127 127 127 127 169 169 169 169 169 169 169 169 217 217 217 217 271 271
Class D
Approximate Diameter of Each Strand mils
mm
Number of Strands
Approximate Diameter of Each Strand mils
mm
64.0 1.63 91 52.4 1.33 70.1 1.78 91 27.4 1.46 75.7 1.92 91 62.0 1.57 81.o 2.06 91 66.3 1.68 85.9 2.18 91 70.3 1.79 90.5 2.30 91 74.1 1.a8 77.7 1.97 127 65.8 1.67 81.2 2.06 127 68.7 1.74 84.5 2.15 127 71.5 1.a2 87.7 2.23 127 74.2 1.a8 90.8 2.31 127 76.8 1.95 800 93.8 2.38 127 79.4 2.02 900 99.4 2.53 127 84.2 2.14 1000 104.8 2.66 127 88.7 2.25 1100 93.1 2.36 169 80.7 2.05 1200 97.2 2.47 169 84.3 2.14 1250 99.2 2.52 169 86.0 2.18 1300 101.2 2.57 169 87.7 2.23 2.31 1400 105.0 2.67 169 91.o 1500 108.7 2.76 169 94.2 2.39 1600 97.3 2.47 217 85.9 2.18 1700 100.3 2.55 217 88.5 2.25 1750 101.8 2.59 217 89.8 2.28 1800 103.2 2.62 217 91.1 2.31 1900 106.0 2.69 217 93.6 2.38 2000 108.8 2.76 217 96.0 2.44 2250 115.4 2.93 217 101.8 2.59 2500 121.6 3.09 217 107.3 2.73 2750 112.6 2.86 271 100.7 2.56 3000 117.6 2.99 271 105.2 2.67 3250 122.4 3.11 271 109.5 2.78 3500 127.0 3.23 271 113.6 2.89 3750 117.6 2.99 271 117.6 2.99 4000 121.5 3.09 271 121.5 3.09 NOTE: The weights of Class C and Class D conductors are the same as for the equivalent Class i3 conductor (see Table G-2).
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APPENDIX H ETHYLENEALKENE COPOLYMER (EAM) (Informative) The purpose of this discussion is to familiarize the reader with the chemical designation, EAM. Cable manufacturers may desire to supply a filled or unfilled EAM compound where specifications require a thennoset material such as XLPE, TRMPE or EPR. Ethylene alkene copolymer (EAM) is the ASTM nomenclature (E-Ethyiene, A-Alkene and M-repeating CHZ unit of the saturated polymer backbone) for copolymers consisting of ethylene and an alkene comonomer. The chemical nomenclature 'alkene', which includes ethylene. is defined by the International Union of Pure and Applied Chemistry (IUPAC) in its publication Nomenclature of Organic Chemistry as follows: "Alkenes are hydrocarbons with a carbon-carbon double bond. Specific alkenes are named as a derivative of the parent alkane, which is the saturated form, ¡.e., no carbon-carbon double or triple bonds. Alkanes are named according to the number of carbon atoms in the chain. The first four members of the alkane series (methane, ethane, propane, and butane) came into common use before any attempt was made to systematize nomenclature. Those with 5 and greater carbon atoms are derived from Greek numbers (Penta, hexa, etc.)." Continuing technological developments in the manufacture of polymers for wire and cable applications have resulted in the ability to polymerize (chemically join) ethylene with other monomers such as butene, hexene and octene rather than the conventional propylene. Polymers can be manufactured in various ways, as can any copolymer of ethylene and an alkene. These variations include the type of polymerization catalystlco-catalyst, process conditions, molecular weight, ethylene/comonomer ratio, and ethylene (or comonomer) distribution. The resultant polymers may provide improvements while complying with applicable requirements in ICEA standards. As the industry progresses towards performance based standards, it is appropriate to consider a more general material classification such as EAM, rather than create a series of ethylene based polymeric designations, such as EO (Ethylene Octene), EH (Ethylene Hexene) or EB (Ethylene Butene).
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APPENDIX I SPECIFICATION FOR ALLOY LEAD SHEATHS (Informative)
II PURPOSE The purpose of this appendix is to provide a definition for a number of alloy lead sheaths that have been used with insulated cables. It is not intended to be a comprehensive listing. Other alloy lead sheaths may be furnished if the composition is mutually agreed upon by the purchaser and the manufacturer.
12 MATERIALS This appendix defines refined lead in pig form for the 1/2C, E,F-3 and copper bearing arsenical alloy lead sheaths as permitted by Part 6 of this standard.
13 REQUIREMENTS The lead shall meet all requirements of ASTM 6 29 except the chemical composition in percent by weight shall be in accordance with Table 1-1. TABLE 1-1 CHEMICAL REQUIREMENTS FOR ALLOY LEAD SHEATHS
Note(s):Alloy 1/2C and Alloy E lead types are considered to be "soff alloys. Alloy F-3 and CopperBearing Arsenical lead types are considered to be "hard" alloys.
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