A three phase transformer having a line voltage ratio of 400/33000 V is connected in the star-delta. The CTs on the 400V side have a CT ratio of 1000/5. What must be the ratio of CTs on the 33000 side?
The neutral of the three phase 20 MVA, 11kV alternator is earthed through a resistance of 5 ohms, the relay is set to operate when there is an out of balance current of 1.5 A. The CTs have a ratio of 1000/5. What percentage of the winding is protected against L-G faults?
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While a transformer is energised, the differentially connected relay will
If a transformer is provided with differentially connected relay. To prevent the mal operation of the relay, the relay restraining coil is biased with __________.
The factor which influences the acr de ionisation dominantly ________
A three phase transformer having a line voltage ratio of 400/33000 V is connected in the star-delta. The CTs on the 400V side have a CT ratio of 1000/5. What will be the current through the pilot wire?
The neutral of the three phase 20 MVA, 11kV alternator is earthed through a resistance of 5 ohms, the relay is set to operate when there is an out of balance current of 1.5 A. The CTs have a ratio of 100/5. What should be the minimum value of the earthing resistance to protect 90% of winding?
The frequency of the carrier in the case of carrier-current-pilot scheme is in the range of _________
Which of the following protection is normally not provided on small distribution transformers?
Breaking capacity of a circuit breaker is usually expressed in terms of ______.