Cores of large transformers are built upto nearly circular cross section in order to reduce Eddy current loss Leakage reactance Iron losses Copper loss TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following protection is normally not provided on small distribution transformers? Buchholz relay Overcurrent protection All of these Overfluxing protection TRUE ANSWER : ? YOUR ANSWER : ?
Transformer having ratings less than 5kVA are generally ______ Natural air cooled Oil cooled None of the listed here Water cooled TRUE ANSWER : ? YOUR ANSWER : ?
The path of the magnetic flux in transformer should have low resistance low reactance high resistance high reluctance TRUE ANSWER : ? YOUR ANSWER : ?
When load on a transformer is decreased, ______loss is decreased Hysteresis Eddy current Friction Copper TRUE ANSWER : ? YOUR ANSWER : ?
A transformer has a 1:6 turns ratio and a secondary coil load resistance of 470 . The load resistance as seen by the source is 7.8 Ω 1.3 Ω 78 Ω 13 Ω TRUE ANSWER : ? YOUR ANSWER : ?
If a power transformer is operated at very high frequencies, then ______ Core losses will be excessive Primary reactance is too much increased Primary will draw large power None of the listed here TRUE ANSWER : ? YOUR ANSWER : ?
A transformer has full load copper loss of 400 W. The copper loss at half full load will be _____. 100 W 400 W 200 W None of the listed here TRUE ANSWER : ? YOUR ANSWER : ?
The leakage flux in a transformer depends upon load current load current, voltage, frequency and power factor load current, voltage and frequency load current and voltage TRUE ANSWER : ? YOUR ANSWER : ?
A transformer with a 110 V primary has a 15:1 turns ratio. The load resistance, RL, is 120 . What is the approximate voltage across the load? 880 V 73 V 88 V 7.3 V TRUE ANSWER : ? YOUR ANSWER : ?