The power transformer is a (a) Constant current device (c) Constant power device (b) Constant voltage device (d) Pulsating main flux device

1 Answer

Answer :

The power transformer is a Pulsating main flux device

Related questions

Last Answer : Power = voltage X Current As per the windings in the primary side and secondary side the voltage and current will change accordingly.

Description : Explain the criteria of selection of power transformer.

Last Answer : Selection Criteria for Power Transformer:  1) Ratings - The kVA ratings should comply with IS:10028 (Part l)-1985. The noload secondary voltage should be 5 % more than nominal voltage to ... ) Cooling - The transformers covered in this group are generally ONAN, ONAN/ONAF, ONAN/ONAF/OFAF.

Description : What will be the efficiency when the transformer operates at unity power factor and 60% of full load 

Last Answer : What will be the efficiency when the transformer operates at unity power factor and 60% of full load 96.5%

Description : What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage:  (A) Eddy Current and Hysteresis losses will be ... Current will be too much high  (C) Transformer may start to smoke and burn  (D) No effect

Last Answer : What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage:  (A) Eddy Current and Hysteresis losses will be ... will be too much high  (C) Transformer may start to smoke and burn  (D) No effect

Description : A 230 V/460 V single-phase transformer operating at 20 A and unity power factor has primary referred resistance of 0.2 Ω and reactance of 0.5 Ω. The approximate primary induced emf is (A) 216 V (B) 226 V (C) 234 V (D) 236 V

Last Answer : A 230 V/460 V single-phase transformer operating at 20 A and unity power factor has primary referred resistance of 0.2 Ω and reactance of 0.5 Ω. The approximate primary induced emf is 226 V

Description :  A 1000 V/400 V power transformer has a nominal short-circuit voltage Vsc = 40%. Which one of the following statements is correct ?  (a) A voltage of 400 V appears across the short-circuited ... V.  (d) The primary voltage drops to 400 V, when the secondary terminals are short-circuited.

Last Answer :  A 1000 V/400 V power transformer has a nominal short-circuit voltage Vsc = 40%. Which one of the following statements is correct ? (a) A voltage of 400 V appears across the short-circuited ... 400 V. (d) The primary voltage drops to 400 V, when the secondary terminals are short-circuited.

Description : A two -winding single phase transformer has a voltage regulation of 4.5% at full - load and unity power -factor. At full -load and 0.80 lagging power-factor, the voltage regulation will be: (A) 4.5% (B) less than 4.5% (C) more than 4.5% (D) none of the above

Last Answer : A two -winding single phase transformer has a voltage regulation of 4.5% at full - load and unity power -factor. At full -load and 0.80 lagging power-factor, the voltage regulation will be: more than 4.5%

Description : if the rated voltage from the power lines is applied to the primary of a single-phase transformer which is operated on no-load, then

Last Answer : if the rated voltage from the power lines is applied to the primary of a single-phase transformer which is operated on no-load, then input voltage is sinusoidal and input current is non sinusoidal.

Last Answer : Much higher efficiency of transformer compared with that of electrical motors of the same power.