Ct

[miguel]

Hello,

What is a CT? And what is its porpuse in a diesel generator?

Thanks

Miguel

[wellandpower]

A CT is a "current transformer".

It is used to transform the current in a cable down to a lower level. So sor example, an 800kVA running at 400~230V would have a peak current of 1160Amps approx. A CT with a ratio of 1250/5 would be fitted.
This CT would therefore output 5 Amps, when the current in the cable was 1250Amps, 2.5 Amps when it was 625Amps in the cable and 0 when there was not current flowing.

The CT reduces the current and therefore allows measurement of the current away from the cable, with a smaller output.