Overpotential test on Dry Type Transformer

[junie]

Would anyone out there teach me the proper procedure on how to perform overpotential test on a 12000/480 Volt, 2000 kVA transformer? Do we need to short the secondary windings if we are testing the primary side? Is there any reference document for the DC test voltage to be applied?

Please help.

Junie

 

[iceworm]

Would anyone out there teach me the proper procedure on how to perform overpotential test on a 12000/480 Volt, 2000 kVA transformer? Do we need to short the secondary windings if we are testing the primary side? Is there any reference document for the DC test voltage to be applied?

Please help.

Junie

Junie -
I've never seen the term "overpotential test" as applied to transformers. So I'm not sure what exactly you are trying to do. I wouldn't worry too much about that though - it would only be one of many things I don't know.

... Is there any reference document for the DC test voltage to be applied?

This sounds like you are thinking of putting a highpot on the primary. That's not usually anything one would do. Mostly I've use Doble, Power Factor, Tan-Delta test equipment - not a DC Hipot.

Your profile says you are a field engineer. Does the company you work for have any specs? does the customer have any specs? Is this a new installation? or an existing xfm with problems?

Without knowing any of this, the best recomendation I could give is to read the IEEE standards on transformer testing.

the worm

 

[zog]

I agree with the worm, I would hope your company has procedures if you are a field engineer, ANSI/NETA test standards would be a good place to start but it tells you what to test, what tets voltages to use and what specs are for acceptance, it does not tell you how. From the sounds of it you may want to hire a testing company to do this for you.