Old CT name plate detail 1

[RRaghunath]

I have come across a old CT with name plate details: KI.1 and n>10 apart from CT ratio. What does KI and n stand for. The CTs are older than 20 years.

Any help!

Thanks in anticipation.

 

[scottf]

I imagine that it's Kl. 1, which means class 1.0, i.e. 1% accuracy. N>10 probably means that it doesn't saturate until over 10 times rated current, however...since Cl. 1 is technically a metering class, it probably reads N<10, which is the security factor, meaning that it will saturate before 10 times overcurrent to protect the meter.

 

[jghrist]

Older German standards used Class 1 (1% current error at 1 or 1.2 x In) or Class 3 for protection cores. In this case, saturation factor n (multiple of In at which current error at rated burden reaches -10%) would be >10.