Transformer commissioning and testing
Transformer commissioning and testing
(OP)
We have a startup processing plant that is in the process of being constructed, and has not yet reached commissioning phase. As part of the plant, a number of second hand transformers were purchased, with varying condition.
I believe that it is appropriate to arrange for these to be tested before being put into service, or even installed, but being new to this, I'm not sure exactly what tests would be required. I'd imagine that the usual insulation tests with new oil would be appropriate, as would an oil analysis test.
The transformers range in size from 25kVA up to 5MVA. Transformers are privately owned and don't require separate utility testing. All transformers are oil cooled, some ONAN cooling, and at least two are OASIC.
I'd appreciate hearing your suggestions.
I believe that it is appropriate to arrange for these to be tested before being put into service, or even installed, but being new to this, I'm not sure exactly what tests would be required. I'd imagine that the usual insulation tests with new oil would be appropriate, as would an oil analysis test.
The transformers range in size from 25kVA up to 5MVA. Transformers are privately owned and don't require separate utility testing. All transformers are oil cooled, some ONAN cooling, and at least two are OASIC.
I'd appreciate hearing your suggestions.






RE: Transformer commissioning and testing
At a minimum I'd think you'd want an as found oil test, particularly looking for water in the oil. Then probably new oil and enough vacuum to thoroughly dry them out followed by all the standard electrical tests. Once the electrical tests are completed check the oil again.
RE: Transformer commissioning and testing
I appreciate your suggestions.
RE: Transformer commissioning and testing
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Sometimes I wake up Grumpy.
Other times I just let her sleep!
RE: Transformer commissioning and testing
Transformers are American in manufacture, site location is Australia.
I believe that the transformers are not a common item, and thus testing is vitally important in case they need to be repaired / replaced.
RE: Transformer commissioning and testing
Basically you can have the idea what all can be tested by looking what
http://www.transformerservices.com/
have in offer from testing.
RE: Transformer commissioning and testing
RE: Transformer commissioning and testing
With regards to the American equipment, the gear was manufactured in the US specifically for use in Australia, and was purchased second hand by us. So we don't have the 50Hz issue, thankfully. The American equipment was picked up as a complete package.
RE: Transformer commissioning and testing
0. ratio
1. no load
2. resistance
3. isolation
4. I didn't see what are voltage ratings, but tandelta/powera factor test is nessessery
5. short circuit impedance
6. any bushings? - tandelta tests
7. oil probe test
Something terrible is stalking between the high voltage potentials
RE: Transformer commissioning and testing
RE: Transformer commissioning and testing
The short circuit test is usually performed with a controllable low voltage supply being used to circulate current in one winding of the transformer with the other winding shorted. Test current is limited to rated current. It's a different test to the fault withstand test with I think is what you're describing.
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Sometimes I wake up Grumpy.
Other times I just let her sleep!
RE: Transformer commissioning and testing
Now, you are have big mistake!!!!!!
I'm Slava, sslobadan is Slobodan.
BTW, I don't have any problem with SC impedance test, but I
think it's usually tested only in mnf.
Regards.
Slava
RE: Transformer commissioning and testing
RE: Transformer commissioning and testing
My apologies to you both. I obviously can't read what is in front of my eyes. I will pay more attention in future!!
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Sometimes I wake up Grumpy.
Other times I just let her sleep!
RE: Transformer commissioning and testing
I'm only joke
Slobodan, we are have problem, both of us start from Sl.
Best Regards.
Slava