Recent questions tagged ct

Description : Mention the precautions to be taken while connecting CT and PT in the circuit. 

Last Answer : Precautions to be taken while using instrument transformers: 1. Secondary of CT is never kept open circuited when it is energized. 2. Secondary of PT is never kept short circuited when it ... of the instrument transformers unless they are properly grounded. 8. Never connect to DC circuits.

Description : Write any four differences between CT and PT.

Last Answer : CT PT CT corresponds to current transformer PT corresponds to potential transformer CT primary is connected in series with load and secondary winding is connected to a low range ammeter. PT ... ) x PT ratio It is a step-up transformer. It is a step-down transformer

Description : Why CT is never operated with an open secondary ?

Last Answer : CT secondary should never be kept open because it will cause saturation of the core to a high level and very high voltage will appear across the secondary which can breakdown the insulation. One terminal of PT secondary is always grounded to avoid capacitive induction and for human safety

Description : If the fault current is 6000 A, the relay plug setting is 150% and the CT ratio is 400/5, the plug setting multiplier will be

Last Answer : If the fault current is 6000 A, the relay plug setting is 150% and the CT ratio is 400/5, the plug setting multiplier will be 10