What is the difference between CT for protection and Ct for
metering?

Answer Posted / debashisdb

Two major differences:

1. Accuracy class: Metering needs high accuracy at load
current while Protection need not have that high accuracy.

2. Safety Factor: It determines the multiplicity of load
current at which the CT saturates. Metering ct should have
lesser value so that it saturates before the meters can get
damaged due to some abnormality. Protection should have
high value since its main purpose desires the ct to
withstand high fault currents to be sensed back to the
relays.

There is another special class ct that combines the
features of both the above used for differential protection.

Is This Answer Correct ?    93 Yes 12 No



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