In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes areÂ hysteresis and eddy current losses.

For a transformer, operating at constant load current, maximum efficiency will occur at? Answer : For a transformer, operating at constant load current, maximum efficiency will occur atÂ unity power factor. ...

In an actual transformer the iron loss remains practically constant from no load to full load becaus Answer : In an actual transformer the iron loss remains practically constant from no load to full load becauseÂ core flux remains practically constant. ...

The maximum constant load torque under which a synchronous motor will pull into synchronism at rat Answer : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known asÂ pull-in torque. ...

A transformer has negative voltage regulation when its load power factor isÂ Â (1) Zero (2) Unity (3 Answer : Leading...

Reduction in core losses and increase in permeability are obtained with transformer employing? Answer : Reduction in core losses and increase in permeability are obtained with transformer employingÂ core built-up of laminations of cold rolled grain oriented steel. ...

In a synchronous motor which losses varies with load? Answer : In a synchronous motor, copper losses varies with load. ...

In synchronous motor, does the winding losses vary with load? Answer : No, in the synchronous motor the winding losses do not vary with load. ...

Explain the electrical losses of magnetic materials used for the cores of inductors and transformer. Answer : Magnetic materials used in the cores of inductors and transformers experience electrical losses primarily due to two main factors: hysteresis losses and eddy current losses. 1. **Hysteresis Losses**: - **Cause**: These losses occur due to the lag between the change in the magnetic field and the ...

Answer : An ideal transformer will have maximum efficiency at a load such that copper loss equal to iron loss. ...

The maximum load that a power transformer can carry is limited by its? Answer : The maximum load that a power transformer can carry is limited by itsÂ voltage ratio. ...

In a step-down transformer, there is a change of 15 A in the load current. This results in change Answer : In a step-down transformer, there is a change of 15 A in the load current. This results in change of supply current of less than 15A. ...

A 3 -phase, fully controlled, converter is feeding power into a DC load at a constant current of 150 Answer : Please show the solution for this question...

Negative voltage regulation is indicative that the load is? Answer : Negative voltage regulation is indicative that the load isÂ capacitive. ...

Minimum voltage regulation occurs when the power factor of the load is? Answer : Minimum voltage regulation occurs when the power factor of the load is leading. ...

A good voltage regulation of a transformer means? Answer : A good voltage regulation of a transformer meansÂ output voltage fluctuation from no load to full load is least. ...

The voltage transformation ratio of a transformer is equal to the ratio of? Answer : The voltage transformation ratio of a transformer is equal to the ratio ofÂ secondary induced e.m.f. to primary induced e.m.f. ...

If a transformer is switched on to a voltage more than the rated voltage? Answer : If a transformer is switched on to a voltage more than the rated voltage its power factor will deteriorate. ...

Auto-transformer makes effective saving on copper and copper losses, when its transformation ratio Answer : Auto-transformer makes effective saving on copper and copper losses, when its transformation ratio is approximatelyÂ equal to 1. ...

A dc chopper is fed from a constant voltage mains the duty ratio of chopper is progressively increa Answer : A dc chopper is fed from a constant voltage mains the duty ratio of chopper is progressively increased while the chopper feeds an RL load. The per unit current ripple wouldÂ increase to a maximum value atÂ Î±Â = 0.5 and then decrease ...

A 40 kVA transformer has a core loss of 400 W and a full load copper loss of 800 W. The proportion o Answer : A 40 kVA transformer has a core loss of 400 W and a full load copper loss of 800 W. The proportion of full load at maximum efficiency isÂ 0.707 ...

A transformer operates 24 hours day at full -load. It's full -load efficiency is :Â (A) equal all d Answer : A transformer operates 24 hours day at full -load. It's full -load efficiency is :Â equal all day efficiencyÂ ...

Losses which occur in rotating electric machines and do not occur in transformers are? Answer : Friction losses windage lossesÂ ...

Answer : The no load current in a transformer lags behind the applied voltage by an angle of aboutÂ 75Â°. ...

An SSB transmitter produces a peak-to-peak voltage of 200 V across a 100 Î© antenna load. What is the Answer : An SSB transmitter produces a peak-to-peak voltage of 200 V across a 100 Ω antenna load. What is the Peak Envelope Power? A) 49.98 W B) 79.98 W C) 99.96 W D) 199.93 W ...

A zener voltage regulator has load requirements of 12 V and 2 A. The zener diode minimum current req Answer : A zener voltage regulator has load requirements of 12 V and 2 A. The zener diode minimum current requirement is 0.2 A. The minimum voltage at input is 24 V. What is the required value of series resistance with source? A) 5.45 Ω B) 6 Ω C) 7.2 Ω D) 6.38 Ω ...

A 3-phase voltage source inverter operates in 180Â° conduction mode with a star connected resistive l Answer : A 3-phase voltage source inverter operates in 180Â° conduction mode with a star connected resistive load. If input dc voltage is 100 V, then the peak to peak output line voltage is :Â 200 V ...

Answer : In a level compounded D.C. generator, full load terminal voltage isÂ equal to no-load terminal voltage. ...

Answer : In over compounded generator, full load terminal voltage isÂ more than no load terminal voltage. ...

Answer : Induction cup relay is operated due to changes inÂ current,Â voltage,Â impedance. ...

Step-down transformer converts high voltage and low current into:Â (A) How voltage and high current Answer : Step-down transformer converts high voltage and low current into:Â Low voltage and high current ...

The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be :Â (A) 34. Answer : The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be :Â 34.64 kVA ...

What is a capacitor voltage transformer? A) It is a transformer used in power systems to step up lo Answer : What is a capacitor voltage transformer? A) It is a transformer used in power systems to step up low voltage signals and provide extra high voltage B) It is a transformer used in power systems to step up high voltage signals and provide extra high voltage C) It is a transformer used in power ...

What is impulse voltage of transformer?

Answer : yes High Voltage side of Transformer winding have more number of turns. and low voltage side of Transformer winding have less number of turns....

For given applied voltage, with the increase in frequency of the applied voltage? Answer : For given applied voltage, with the increase in frequency of the applied voltageÂ eddy current loss will remain unchanged. ...

Answer : When a given transformer is run at its rated voltage but reduced frequency, itsÂ core flux density is increased. ...

Even at no-load, a transformer draws current from the mains. Why? Answer : Even at no-load, a transformer draws a small amount of current from the mains. This is due to two main reasons: 1. **Magnetizing Current**: To create the magnetic field in the core, the transformer needs a magnetizing current. This current is necessary to establish and maintain the magnetic flux in...

Answer : No-load current in a transformerÂ lags behind the voltage by about 75Â°. ...

Answer : No-load current of a transformer has small magnitude and low power factor. ...

Answer : The full-load copper loss of a transÂ¬former is 1600 W. At half-load, the copper loss will beÂ 400 W. ...

A no-load test is performed on a transformer to determine? Answer : A no-load test is performed on a transformer to determineÂ magnetizing current and loss. ...

Which of the following can reduce the Eddy current losses? A) By making the core of a stack of plat Answer : Which of the following can reduce the Eddy current losses? A) By making the core of a stack of plates electrically insulated from each other B) By making the core of solid block C) By increasing the applied voltageÂ D) None of these ...

Explain the â€śmitigation of power theftâ€ť and â€śfaulty meter replacementâ€ť for energy conservation techn Answer : Energy conservation techniques to reduce commercial losses:Â 1. Mitigation of Power Theft: Power theft being the most important issue which all of the service providing utilities face. It necessitates some strong steps towards mitigation of power theft. State government can contribute in this by ...

The friction losses in Real Transformers are :Â (A) 0% (B) 5% (C) 25% (D) 50% Answer : A...

In DC motor iron losses are occurred in? Answer : In DC motor iron losses are occurred in the armature. ...

Answer : Iron losses in a D.C. machine are independent of variations inÂ load. ...

Answer : In case of D.C. machines, mechanical losses are primary function ofÂ speed. ...

What are the losses in a transmission line? Answer : In a transmission line, losses typically fall into three main categories: 1. **Resistive Losses (IÂ˛R Losses):** These occur due to the resistance of the conductors in the transmission line. As electrical current flows through the conductors, some energy is converted into heat due to the resistance ...

What are the types of power losses in inductor? Answer : Copper losses, Eddy current loss, and hysteresis loss are the types of power losses in inductor. ...

Answer : Iron loss, copper loss and mechanical losses these are the losses in DC machine....

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