CT Ratio Selection

[Cerkit]

Hi,

I am looking at a 22/400kV 600MVA transformer. I am looking at CT sizes for the LV side of the transformer. For full load current the current is 15745A. Is it possible to use a 16000/1 CT or does this ratio of CT not exist?

Thanks

 

[Parchie]

@Cerkit,
What is that CT for? AFAIK, at that range, you can find bushing CTs for that. If you wanted a CT for metering, a 16,000/5 is fine. If you want to use it for protection, a 22,000/5 would be better.

 

[veritas]

I have worked with 19000/1 CT's for a 660MW generator for protection purposes. But yes, what are the CT's for? If for protection please state what kind of protection.