Test winding in current transformer

[kssschsekhar]

Dear Folks,
One of the current transformers has an additional test winding i.e.10A & 45 turns. Main CT ratio is 450-300/1A. Please share your view the purpose of the test winding. Advanced thanks.....

 

[Marmite]

It's for testing by injecting current. Usually provided on CT's where you can't get to the primary connections easily to perform primary injection tests, such as CT's within transformer bushings.
Regards
Marmite

 

[kssschsekhar]

Thanks Marmite for the information. How do choose number of turns and current rating of the test winding?

 

[defreitas]

I have seen this sort of set up for a WIC 1 protection relay, where a "test winding" is provided, so you can secondary inject into the relay and test it...

Just like Marmite said...

Have a look at the manual I have attached to this forum.

I hope that has helped.



Dan de Freitas
Field Services