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Generators for peak load plants are usually designed for maximum efficiency at 50 to 75 percent full load.

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Description : What is base load and peak load power plants?

Description : For a transformer, operating at constant load current, maximum efficiency will occur at?

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Description : Compare base load plant with peak load plant. 

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Answer : The condition for maximum efficiency for a D.C. generator is variable losses equal to constant losses.

Description : Compare base load plant with peak load plant on any two points.

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Description : 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

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Answer : Transformer efficiency is maximum when copper losses are equal to iron losses.

Description : A transformer operates 24 hours day at full -load. It's full -load efficiency is :  (A) equal all day efficiency (B) more than all -day efficiency (C) less than all -day efficiency (D) equal to maximum efficiency

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

Description : The efficiency of two identical transformers under load conditions can be determined by?

Answer : The efficiency of two identical transformers under load conditions can be determined by back-to-back test.

Description : A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is (A) 28.2 mm (B) 26.4 mm (C) 24.4 mm (D) 22.0 mm

Answer : A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is 22.0 mm

Description : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as?

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

Description : 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 its voltage ratio.

Description : The synchronous motor will develop maximum power when the load angle is?

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Description : In hydroelectric power plants  (1) both operating and initial cost are high (2) both operating and initial cost are low (3) operating cost is low and initial cost is high (4) operating cost is high and initial cost is low

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Description : The rankine cycle efficiency of steam power plant is  (1) 60-80% (3) 30-45% (2) 45-80% (4) 20-30%

Answer : The rankine cycle efficiency of steam power plant is 30-45%

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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

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Description : Two synchronous generators G1, G2 are operating in parallel and are equally sharing KVAR (Lag) component of load. To shift part of KVAR from G2 to G1, while keeping terminal voltage fixed, the following action must be done

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Answer : In D.C. generators the pole shoes are fastened to the pole core by counter sunk screws.

Description : In DC generators lamination core are generally made of?

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