14

15 a)

b)

16 a)

10000EE405122001

industry. This transformer is connected to 11kV supply through an over-head line
of length 2 km. The conductor used is RABBIT with an equilateral spacing of
900 mm. The percentage reactance of the transformer is 3.5% and the full load
copper loss of the transformer is 2%. The three-phase short circuit power at the
utility substation is 300MVA. The resistance of the line conductor is 0.454Q/km.
Calculate the following parameters at the primary and secondary of the
transformer. a) Initial symmetrical short circuit current and b) peak short circuit
current. Any missing data may be assumed
The following motors have to be installed in 8 plastic manufacturing industry (10)

1. 5.5hp, three phase motor (M1)

ii. 3hp, three phase motor (M2)

iii. 1.580, single phase motor (M3)

iv. ۷۸ hp, single phase motor (M4)
The positions of the machines are given below. Select the suitable components
for the motor wiring system and draw the wiring circuit diagram with required

components. Any missing data may be assumed

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30m

PART 0
Answer any two full questions, each carries 10 marks.

Explain Coefficient of utilisation and LLF in illumination systems. Explain in (5)
detail the factors affecting LLF?

State the importance of LLF and CU in lighting design. An illumination of 300 (5)
lux is to be produced on the floor of a room 12m x 9m. 10W LED lamps of
1000lumens are used for the installation. Considering CU and LLF as 0.7,
calculate the number of lamps required for the installation.

How can we optimize the energy consumption in lighting and power circuits? (5)

Suggest effective energy conservation techniques for domestic application.