ct polarity testing 3

[golruss]

Hi I have a 230 kv ABB SF6 bkr to install and polarity teting of the bkr. CTs are required. I would like to use a lantern battery and a analog voltmeter connected to the secondary of the ct while flashing the primary with the battery. Confirm if I am doing this test correctly.
Thanks

 

[Skogsgurra]

Yes. That is one of the oldest and safest ways of doing it. Polarity of deflection and battery shal be the same when closing the circuit. Opposite when opening it - but it usually is a lot shorter in duration and perhaps difficult to observe when openeing.

 

[cuky2000]

Check if the enclose refrences could help

http://www.kilowattclassroom.com/Archive/CTTesting.pdf

http://www.kilowattclassroom.com/Archive/CurrentTransf.pdf

http://www.eettaiwan.com/ARTICLES/2002MAY/PDF/2002MAY13_AMD_ID_POW_DA_AN415.PDF

 

[busbar]

Other references for DC-polarity testing in transformers are

http://www.geindustrial.com/products/applications/GET-97D.pdf

§3 and ANSI/IEEE C57.13.1-1981 §7.