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b. A balanced three phase star connected load is connected across a 400 V three phase
ac supply. Power consumed by the load is measured using two wattmeter method. The
readings of the two wattmeters are -500 W and 1500 W. Find the current drawn from
the supply and the power factor of the load. (5)

‎With the help of a neat diagram, explain the working of a thermal power plant.‏ ۔

‎(10)

‎മ. With the help of a diagram, explain a power transmission scheme. (5)

‎b. What are the equipments in a substation? Explain the function of each equipment.

‎(5)
‎MODULE 5
Answer any one full question
. ೩. What are the parts of a ‏عل‎ generator? Explain each part. (5)

‎b. A 150 kVA transformer has an iron loss of 700 W and a full load copper loss of
1800 W. Calculate the efficiency at full load, 0.8 power factor lagging. (5)

‎OR

‎_a. A 120 V de shunt motor draws a current of 200 A. The armature resistance is 0.02 Q

‎and shunt 11016 resistance 30 62. Find the back emf. (5)

‎b. A30 kVA, single phase transformer has 500 primary turns and 30 secondary turns.
The primary is connected to a 3300V, 50 Hz supply. Calculate (i) the maximum flux
in the core, (ii) the secondary emf, (ili) the primary and secondary currents. (5)

‎MODULE 6
Answer any one full question

‎. 8. How does a three phase induction motor start? (5)

‎b. What are the different types of three phase induction motors? What are their
advantages and disadvantages? (5)

‎OR

‎8. The frequency of the emf in the stator of a 4 pole induction motor is 50 Hz, and that
in the rotor is 1.5 Hz. What is the slip and at what speed is the motor running? (5)

‎0, Why a single phase induction motor is not self starting? How it can be made self
starting? (5)

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