Circuit Diagram of Loaded Current Transformer and Potential Transformer

Circuit Diagram of Loaded Current Transformer and Potential Transformer Points : Circuit Diagram of Loaded Current Transformer and Potential Transformer Shows C.T. and PT. connected with the load to measure load current, potential & the current coil of wattmeter is connected through C.T. and standard 5°A ammeter. The potential coil of wattmeter is connected with P.T. and standard 110 V voltmeter.

Rating of P.T. The potential transformers are standardized at from 100 to 120V secondary voltage. A 110V voltmeter may be used to measure a voltage of 66KV with the help of a 66,0000/11OV potential transformer. Therefore, very cheap moderate rating instruments may be used to measure high voltages.
The potential transformers may be indoor or outdoor type. The following table shows typical standard potential transformer ratios.