Hi all - just wanted to check on what oil properties to check for the above 400V 400A 25MVA- similar to transformer oil test slate or different. Obviously no paper involved I guess.
Oil = Shell Vitrea 31.

Mike.

This message has been edited. Last edited by: mike66,

What type of a component are you sampling the oil from? An outdoor oil circuit breaker?

No, indoor units in a substation on site.
There are 4 of them connecting incoming power to site.
They are quite old and the contacts (from what I have been told) are immersed in oil.
To get to the oil the units are jacked upward out of drums of oil.

Mike.

It sounds like an oil circuit breaker. I didn 't realize they had those in indoor switchgear.

If that's what it is, the test parameters are similar to transformers. Mostly DGA, dielectric strength, moisture (although limits may be different, particularly on the DGA). Additionally, particle analysis is more common/valuable on OCB's than transformers due to moving parts and moving contacts.

Some links:

http://www.weidmann-acti.com/u/productdocs/ocb_diagnostic_evaluation.pdf

http://www.tjh2b.com/asp/articles/boa.asp

Thanks for that info Pete -yes they're a bit old circa 1950!
I probably need to find out if our local transformer oil analysis boys can also test for metal particles - otherwise I guess its two samples out.

Mike.