METHOD OF STATEMENT FOR INSTALLATION OF EARTHING/GROUNDING SYSTEM & LIGHTNING PROTECTION SYSTEM 1. INTRODUC INTRODUCTION TION & SCOPE SCOPE OF OF WORKS WORKS : This Method statement details the procedure procedure of installation & testing of Earthing/Grounding Systems and Lightning Protection Systems. The Grounding System / Lightning Protection Protection System are designed to ensure the complete safety of both persons and equipment throughout the Plant for its buildings co!ered under the pro"ect Scope# a. b. c. d. e.
Substa Substatio tion n $uild $uilding ing % %' ' Substation Substation buildin building g () & *inishi *inishing ng o+ces. o+ces. ,emote emote -nstr -nstrume uments nts $uild $uilding ing ,ubber ubber *inish *inishing ing $uilding. $uilding. os. os. pera perator tors s Shelte Shelters. rs. 0s $S E/-E1 2')34 Lightning protection standard5 standard 5 the required earth resistance for lightning protection System is belo6 73 8
2. REFE REFERE RENC NCES ES:: o Speci9cation # o Shop dra6ings # :endor; endor;s s recom recommen mendat dation ions/G s/Guid uide e lines lines < Erico/ Erico/Eri Eritec tech h 1ald6e 1ald6eld= ld= o E>othermic ?elding Manual 10@?EL@ Lightning Protection 1onnections 1atalog ,ef 1atalog 07E o o 10@?EL@A ?elded Electrical 1onnections o 10@?EL@A 10@?EL@A ?elded elded Electric Electrical al 1onnectio 1onnections5 ns5 BuicC BuicC ,efer ,eference ence Product Product Guide5 PocCet 1atalog ,ef. ED%'10E 3. SEQUEN SEQUENCE CE OF WORKS WORKS:: 3.1 Mat!"a# Mat!"a# a$% a$% E'"()$ E'"()$t: t: 7 1opper earth rods ' $are copper cable ) 1able clamp for earth rod and copper cable 1opper tape and clips 4 P:1 pipe 2 1oncrete grounding pit. D 1able lugs % 0ir terminal F Earth bar 6ith disconnecting linC 73 E>othermic ?elding Set 77 Earth Tester
7'
*ield Tester
3.2 T*( +, -+$$-t"+$# o 1onnect $are 1opper 1onductor to $are 1opper 1onductor @etail7 1onnect Earth ,od to $are 1opper 1onductor ?ire @etail7. o 1onnect rebar to bare copper 6ire @etail'. o o 1onnect copper bar to bar copper 6ire @etail). o 1onnect cable trays/ladders and pipes to grounding system @etail of electric continuity for cable tray shall be pro!ided in method statement for trays/ladders installation.. 3.3 P!+-%'! +, "$ta##at"+$ +, G!+'$%"$ S*t)# 3.3.1 G$!a# & Sa,t* P!-a't"+$ 0. nly E,-1 manufactured equipment and materials should be used to maCe 10@?EL@A connections. $. @o not connect items e>cept as detailed in instruction sheets. *ailure to comply 6ith these instructions may result in improper and unsafe connections5 damage to items being connected5 bodily in"ury and property damage. 1. @o not use 6orn or broCen equipment 6hich could cause leaCage. @. @o not alter equipment or material 6ithout E,-1 authoriHation. E. ?hen using 10@?EL@A do not use 6elding material pacCage if damaged or not fully intact. *. ?hen using 10@?EL@A PLIS5 do not tamper 6ith or disassemble the 6elding material unit. G. MaCe connections in conformance 6ith 10@?EL@ instructions and all go!erning codes. i.
Personnel should be properly trained in the use of this product and must 6ear safety glasses and glo!es. 0!oid contact 6ith hot materials. ii. 0d!ise nearby personnel of 6elding operations in the area. iii. ,emo!e or protect 9re haHards in the immediate area. i!. Pro!ide adequate !entilation to the 6orC area. !. @o not smoCe 6hen handling starting material. !i. 0!oid direct eye contact 6ith JKash of light from ignition of starting material. . ?elding material is an e>othermic mi>ture and reacts to produce hot molten material 6ith temperatures in e>cess of 733N1 '433N* and a localiHed release of smoCe. These materials are not e>plosi!e. -gnition temperatures are in e>cess of F33N1 7243N* for 6elding material. -. 0dhering to the 10@?EL@ 6elding procedures 6ill minimiHe risC of burns and 9re caused by hot molten material spillage. -n case of 9re5 use of 6ater or 1' 6ill aid in control of burning containers. Large quantities of 6ater 6ill aid in controlling a 9re should the e>othermic materials become in!ol!ed. ?ater should be applied from a distance. O.
i. MaCe sure there is proper mold 9t and assembly of equipment. ii. 0!oid moisture and contaminants in mold and materials being 6elded. 1ontact bet6een hot molten metal and moisture or contaminants may result in spe6ing of hot material. iii. $ase material thicCness must be su+cient for the siHe and type of connection being made to pre!ent meltthrough and leaCage of hot molten metal. . 0pplications or conditions may e>ist 6hich require special considerations. The follo6ing are e>amples5 but are not intended to be a complete listing of applications/conditions.
3.3.2 I$ta##at"+$ +, E0+t!)"- W#%"$ S*t): The mould crucible 6ith suitable siHe shall be used for e>othermic 6elding. a The follo6ing procedures shall be follo6ed before conduct the e>othermic 6elding. i Ensure that the mould is al6ays clean and free of moisture. ii Ensure that the tap hole is al6ays in 6ellde9ned condition. iii Ensure that the correctness of connection selector. i! Ensure that the correctness of 6elding po6der b Procedure to conduct the e>othermic connections. i *i> the connection selector to the handle clamp as per the require siHes of conductor to be 6elded. ii Place the conductor in the mouldQ ensure that connection selector is used in accordance to the conductor to be 6elded. iii 1lose the handle clamp and locC in the locC position5 drop the metal retaining disc into the bottom of the mould crucible. Ensure that the metal retaining disc is correctly5 completely seated and co!er up the tap hole. i! @eposit the 6elding po6er into the crucible and spread a little amount on top of the mould edge as a role of starting po6er. ! 1lose the mould lips5 and ignite 6ith the Kint gun. !i pen the mould after a fe6 seconds 6here the reaction is completed or the metal has been solidi9ed. !ii @o not touch the 6elding surface after the reaction. !iii 1lean up the mould for the ne>t "oint. 3.3.3 Ea!t"$ Ca# I$ta##at"+$: a The earthing conductor5 bare copper cable shall be installed as per appro!ed shop dra6ing. b Ensure that the copper cable is straight not 6a!y so that it 9ts nicely into the e>othermic mould prior to the e>othermic 6elding. c Ensure that the copper cable is free of dirt / oil and dry Ceeping. 3.3. Ea!t R+% I$ta##at"+$: o The copper rod is to be dri!en into the ground by means hammer drill / sledge hammer.
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MaCe sure the rods are coupled 6ith coupling and dri!ing studs before hammering as it 6ill protect the thread or the head of the rods from damaged. 0fter the desired depth has achie!ed5 the earthing conductor 6ill be "oint to the earth bar / rod clamp of the earth pit and fastened it securely. ,esisti!ity checC should be taCen and if the resisti!ity is not achie!ed to required !alue then it is ad!isable to dri!e it deeper. The rod shall be dri!en as deep as possible and does not force to dri!e it as it may breaC the coupler and loose the rod. The number of rods dri!en into the ground 6ill be dependable to the soil resisti!ity on that particular area and as per appro!ed shop dra6ing.
3.3.4 Ea!t P"t: a -nstall the inspection pit and ensure that it is Kush 6ith the e>ternal ground / road le!el. b Ensure that the earth pit is free from dirt and rubbish. 3. Sa,t* -+$t!+# )t+%: a5 G$!a#: The safety procedure generally has to be applied for all Engineers5 Super!isors5 and ?orCers as follo6ing bello6# MaCe sure that all personal protection equipment PPE be pro!ided on o site before starting 6orC such as helmet5 safety boot5 safety glasses5 glo!e5 masC etc. o MaCe sure that PPE must be 6ear in the correctly 6ay 6hen 6orCing. o Tools and equipment shall be inspected by authoriHed person before carried out the 6orC. $arricades and sign posts for 6arning shall be pro!ided on site. o o *ire e>tinguishers shall be pro!ided on site 6here!er e>othermic 6elding 6orCs and al6ays ready to use. 5 W+!6"$ 0+t!)"- 7#%"$: Ensure 6orCer 6ear safety glasses5 glo!es5 helmet etc. o o *ire e>tinguisher shall be al6ays ready at 6orC place -5 W+!6"$ at "t: Ensure e!ery 6orCer 6ear safety harness 6hen 6orCing at more than ' o m height. o Safety protected handrail on top layer of scaRolding shall be pro!ided. o Ensure 0 ladders are in good condition/quality. 3.4 Mat!"a# t+!a:
a Storage of e>othermic 6elding materials should be in a clean5 dry5 J SM-G area and should be restricted to access by authoriHed personnel only. b Storage condition shall be such that e>othermic 6elding materials are not sub"ect to rough handling or physical damage. Storage shall be in cool place and in condition no humidity and moisture. c 0ll bo>es or container of material should be stored in accordance 6ith container carton or label marCing JThis Side Ip d These materials must be stored under shelter to protect the bo>es from the elements and raised to protect them from dampness or 6et surface.
3.8 E0-'t"+$ 7+!6 ,+! Ea!t"$ +, L"t$"$ P!+t-t"+$# o @ri!e the earth rods into the earth by hammer. E>ca!ate a trench @ > ?# %33#433 to linC earth rods together by soft o dra6n bare copper 6ire. LinC earth rods to Grounding net6orC. o o $acC9lling the trench. o Testing and record earthing resistant !alue. o Ooints shall be protected against rust by cold gal!aniHed paint. 1ontact surfaces shall be Kush prior to "ointing. o $olt connections of copper 6ire 6ith hot dip gal!aniHed steel bar and o copper 6ire 6ith copper bar should reach mechanical eRect and electrical eRect. o @uring the dri!ing of the rods into the earth5 it is better to measure !alue of the resistance to earth in order to quantity of necessary grounding rod. 3.9 Ha$%#"$ +, -)"-a# t+ !%'- +"# !"t""t*: o Prepare 6iring trench o Ensure no garbage on the trench Put the chemicals along the tracC co!ers a thicC layer of copper )mm o $acC9lling the trench. o 3.; P!+-%'! +, "$ta##at"+$ +, L"t$"$ P!+t-t"+$ *t)# o The installation of the lightning arresters 6ill be closely coordinated 6ith 0pron *loodlight and roo9ng 6orCs. Grounding system for Lightning protection system must be o The established prior to install Lightning protection system refer to item . for Grounding installation. o The do6nconductor shall not be isolated nor enclosed in P:1 pipe and placed internal in the apron lighting to6ers. o The do6n conductor should be 9>ed 6ith a test "oint in a position that is con!enient for the tests but shall not be reached by irresponsible persons.
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The do6n conductor F4mm' bare copper 6ires shall be connected directly to the mounting base of the lightning arrester by terminal lug. . The lightning arrester should be 9tted into the mounting base before lifting them and connecting to the 0pron *loodlight Mast. 0fter completing the installation of Lightning arrester into the 0pron *loodlight Mast5 it shall ensure that the do6n conductor connecting immediately to the mounting base and the grounding system.
. STANDARD PROCEDURES: o
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@o6n conductor for air terminal ESE type shall be connected to earthing rods to ensure direct connection to earth of any stroCe current before interconnection 6ith the general Grounding System. 0ll equipment connected to po6er supply must be grounded. 0ll metal parts5 structural steel5 cable trays5 piping5 reinforced concrete must be grounded. 0ll "oints shall be according to shop dra6ing. Safety control# To secure an e>it entrance 6hene!er it has contingencies. eep 6ater out 6here is necessary. To Ceep 6orCplace and amenities is al6ays clean. $arricade and sign post are a!ailable around the site 6orC. To pay attention to equipment/ tools as belo6# @rill machine# insulation and earthing terminal 1ylinders# Pressure Gauge Set shall be inspected by authorities 1utting machine# insulation and earthing terminal
4. INSPECTION AND TESTING PROCEDURES# 4.1 I$(-t"+$: o
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The Grounding and Lightning Protection System shall be gi!en a !isual inspection by the Engineer during the installation. The 1ontractor should not allo6 any bacC9lling of trenches or pits 6here these systems are installed before inspection by the Engineer and the appropriate documents are signed. Material deli!ered shall be inspected under the Engineer;s super!isor about siHe5 quality and quantity. 0fter performing5 6orCs shall be inspected. -nspection of lightning should be included t6o steps# checC underground system and general. *or equipment 9tted inside structural 6orC or 9> underground shall be checCed and inspect before bacC9lling. 1hecC Grounding and Lightning Protection. Shopdra6ing appro!ed. Material appro!ed. Test method of !isual#
1hecC quality of grounding conductor and grounding electrode deli!ered on site. 1hecC installation connection5 routing5 and quantity according to appro!ed shop dra6ings. 1hecC dimension5 le!el and 9nishing of foundation of air terminal. 1hecC installation according to appro!ed shop dra6ings and manufacturer;s recommendation. *unctional Test# 0s per design and manufacturer;s recommendation. Grounding ,esistance :alue shall be measured.
4.2 F"#% tt: 4.2.1 G$!a#: Grounding rods shall be tested for ground resistance !alue before any o 6ire is connected. The test shall be performed in normal dry 6eather5 not less than % hours after rainfall. o Ground resistance shall also be measured for each piece of equipment to the ground electrode. Testing shall be 6ith a portable ground testing megger for each ground or group of grounds. The instrument shall be equipped 6ith ammeter reading directly in hms or fractions thereof to indicate the ground !alue of the electrode under test. o 0ll test equipment including test meter shall be pro!ided and one copy of the ground megger manufacturer;s directions5 including the method shall be pro!ided. minimum resistance based on the allo6able capacity of the o The conductor shall be as indicated in the follo6ing table# R"ta$- tt ta#
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'4 through 43
'43333
47 through 733
733333
737 through '33
43333
'37 through 33
'4333
37 through %33
7'333
!er %33
4333
The earth resistance shall be measured either soil resisti!ity testing or earth resistance testing method.
4.2.2 S+"# !"t""t* tt"$ <a% +$ W$$! )t+%: o E'"()$t a$% (!+-%'! ,+! +"# !"t""t* :
The test instrument is used Mega @igital Earth Tester. The instrument is connected to the electrodes as detail belo6#
*our electrodes are dri!en into the ground5 in a straight line 6ith equal spacing bet6een them. Let the spacing be called a.
The soil resisti!ity can then be calculated using the equation# U V ' > ).7 > a > , ?here U V soil resisti!ity ohm meters a V electrode spacing meters , V measured resistance ohms
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Tt P!+-%'!: 1on9rm the proposed test locations. -nsert four electrodes into the ground in a straight line aV ' meters spacing. 1onnect instrument to the electrodes as sho6n abo!e. Perform test and record measured resistance in Soil ,esisti!ity Test *orm. Shift electrodes to ne>t spacing aV meters and repeat test. ,epeat tests aV 2 meters5 % meters and 73 meters electrode spacing. ,ecorded measurements 6ill be analyHed and presented in Soil ,esisti!ity Test ,eport.
8. STATUTE OF COMPLETION: 0fter 9nishing the installation 6orCs of Grounding and Lightning Protection System5 inspection shall be carried out and appro!ed by relati!e parties such as# 1onsultant5 Main contractor. ?e can asC the E>periment 1enter for inspection the 6hole system and then issue the 1erti9cate 1ompletion.
