ABB AB Power Transformers
Nr 1ZSE 209 001-4 2008-06-24, page 1 of 3
This document must not be copied without our written permission, and the contents thereof must not be imparted to a third party nor be used for any unauthorized purpose. Contravention will be prosecuted. ABB Power Technology Products AB Transformers
OIL SAMPLING FOR DISSOLVED GAS ANALYSIS AND OIL QUALITY TEST 1. GENERAL INFORMATION Dissolved gas analyses are used to assess the condition of a transformer based on the gasses dissolved in the oil due to hot surfaces, arcs, partial discharges or other faults. In a diverter switch, gasses normally associated with faults are generated during normal operation. If the diverter switch oil is in contact with the oil in the transformer, directly or by a common oil conservator, any gasses dissolved in the diverter switch can be present in the transformer oil. In these cases, evaluation of the transformer condition by means of the gas content in the oil can be uncertain. An additional sample must then be taken from the conservator. The evaluation is based on the ratios of the gases as well as the absolute values and gas production rates. Further sampling later can therefore enhance the accuracy of the assessment. Oil quality testing measures the condition of the oil not the transformer. It is important that the oil condition does not become deteriorated. A bad oil condition can harm the function of the transformer. 2. SAMPLING VESSELS Oil samples intended for dissolved gas analysis should be taken in 20-ml glass syringes equipped with a valve. Always take two samples from the same place. Oil samples for quality testing should be taken in 1,1L aluminium bottles, equipped with a plastic cap with an aluminium foil. The sampling vessels are provided free of charge by ABB Power Technology Products AB, Transformers. One questionnaire for each unit is provided. Please complete the questionnaires and return them with the oil samples. Please make sure you have entered the vessel index number on the questionnaire correctly. The questionnaire should be completed in conjunction with the sampling. 3. SAMPLING VALVE Suitable sampling valves are cooler, cover or bottom. If the diverter switch oil is in contact with the oil in the Postal Address
ABB AB Power Transformers, dept. AD SE-771 80 LUDVIKA, Sweden Tel. +46 240 78 20 00
transformer, an additional sample should be taken from the conservator. Selecting a sampling valve consider personal safety first and foremost. The valve should be fitted with a connector for connecting to the plastic sampling hose provided. Do not use rubber hoses. 4. SAMPLING Please refer to the separate instruction describing the sampling procedures, 1ZSE 209 001-6. Samples for dissolved gas analysis should be sent in as soon as possible in order to reduce gas leakage to a minimum. 5. PACKAGING The samples can simply be returned in the packaging they arrive in. Feel free to add packaging if necessary. Do not return used plastic hoses and T-pieces. Please remember to enclose the questionnaires. 6. SENDING SAMPLES FOR ANALYSIS Send the appropriately packaged samples to the following address: ABB AB Power Transformers Godsmottagning Torg 24, dept. AD SE-771 80 LUDVIKA, Sweden Some carriers require a street line in the address. If you are using such a carrier, you can add “Valhallavägen 2” after “Godsmottagning”. Staff phone numbers: +46 (240) 783 035 +46 (240) 783 037 +46 (240) 783 081
+46 (240) 783 083 +46 (240) 783 307 +46 (240) 783 812
Telecopier +46 (240) 61 15 68 Email:
[email protected] Mail: ABB AB Power Transformers Department AD SE-771 80 LUDVIKA, Sweden
OIL SAMPLE QUESTIONNAIRE
Nr 1ZSE 209 001-4 2008-06-24, page 2 of 3
Serial number
Project number
(only ABB)
Customer (Required) Company: ................................................................. Name of Contact: .................................................... Postal Address: ...................................................... ........................................................... ....................... ...................................................................................
Reference: ................................... Date: ................ Phone: ..................................................................... Fax: .......................................................................... E-mail: ..................................................................... VAT-number: ..........................................................
Send results to (If other than customer)
Billing address (If other than customer)
Company: .............................................................. Name: …………….................................................. Postal Address: ....................................................
Company: .............................................................. Postal Address: ....................................................
........................................................... .....................
VAT-number: ........................................................
…………………………………………………………..
Type of tests Dissolved gas analysis
Breakdown voltage (BDV)
Moisture content (Moist)
Colour
Basic oil quality (BDV, Moist., NV., Colour)
Neutralisation value (NV)
Interfacial tension (IFT)
Tan δ
Extended oil quality (Basic + IFT, Tan δ, Inh.) Inhibitor content (Inh) Furane content Oil quality syringe (Moist., NV., Colour, Inh.) Other tests………….......................................................................... .............................................................................................................................................................................................
Sampling information (Required) Date of sampling: .........................
Oil temperature at sampling: ……...................... °C.
Load at sampling: ........................% If 0 %, time out of service: ............................ hours. Where the oil pumps in service at time of sampling: Yes No Sampling vessels and sampling places Index No: ...............
Bottom
Cover
Cooler
Conservator
Other ........................
Index No: ...............
Bottom
Cover
Cooler
Conservator
Other ........................
Index No: ...............
Bottom
Cover
Cooler
Conservator
Other ........................
Index No: ...............
Bottom
Cover
Cooler
Conservator
Other ........................
Index No: ...............
Bottom
Cover
Cooler
Conservator
Other ........................
Index No: ...............
Bottom
Cover
Cooler
Conservator
Other ........................
Measures taken Date? ................... Filtering / degassing of oil Was a fine vacuum filter used?
Oil regeneration Yes
Oil change
No
Other: ………................................................................................................................................... ......................................................................................................................................................... .........................................................................................................................................................
OIL SAMPLE QUESTIONNAIRE
Nr 1ZSE 209 001-4 2008-06-24, page 3 of 3
Serial number
Project number
(only ABB)
Object information The following only needs to be completed if this is a first time sampling with our laboratory or if any information has changed since last analysis was performed. General Owner: ...................................................................... Location at present: .............................................. Manufacturer: .......................................................... Designation: ........................................................... Type: ................................................ Oil weight: ..............................kg Application: Voltage: …...................................kV Type of oil: .................................. System / Distribution Power: ..................................MVA(r) Number of oil pumps: ............... Generator Furnace Frequency: .................................Hz Cooling system: ......................... Shunt Smoothing Year of manufacture: .................... Taken into operation: ................ Other........................................... Tap-Changer (TC) De-energised TC On-load TC Type: ……………............................................................................. Type of conservator Shared oil with TC Separate expansion oil TC / Transformer Separate expansion oil but shared air space
No TC
Open Sealed Rubber sack / air cell
Other
Known past malfunctions No
Yes Date
Are any malfunctions known?
.........................
Has the gas relay given alarm?
.........................
Has the gas relay tripped?
.........................
Please describe the nature of the malfunction: ............................................................................... ......................................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... Other observations: ......................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... Comments: ..................................................................................................................................... ......................................................................................................................................................... ......................................................................................................................................................... .........................................................................................................................................................
