1. Energy meter measures the
(A) Power consumed in a specific time
(B) Power of a circuit
(C) Both a & b
(D) Apparent power in volt-amperes
2. An energy meter counts one unit when
(A) 1KW power is used in one minute
(B) 1W power is used in one minute
(C) 1KW power is used in one hour
(D) 1W power is used in one second
3. Commercial unit of electrical energy is
(A) KWH
(B) Watt second (WS)
(C) KW
(D) Joule
4. Energy meter is also called
(A) KWH meter
(B) Both a & b
(C) Watt meter
(D) Watt hour meter
5. Single phase induction type energy meter works on
(A) AC supply only
(B) DC supply
(C) Both on AC & DC supply
(D) Any type of supply
6. This is not a part of single phase energy meter
(A) Braking magnet
(B) Current coil
(C) Control spring
(D) Pressure coil
7. Electromechanical type Energy meters being used nowadays
(A) Clock type
(B) Commutator motor type
(C) Induction type
(D) Electrolytic type
8. The shape of electromagnet of pressure coil of single phase energy meter is
(A) None of these
(B) U shaped
(C) L shaped
(D) E shaped
9. The shape of electromagnet of current coil of single phase energy meter is
(A) E shaped
(B) U shaped
(C) L shaped
(D) S shaped
10. Number of terminals used in the single phase energy meter are
(A) 06
(B) 04
(C) 02
(D) 07
11. The magnet used in single phase energy meter
(A) Electromagnet
(B) Permanent magnet
(C) Both a & b
(D) None of these
12. The permanent magnet used in single phase energy meter is called
(A) Control magnet
(B) None of these
(C) Electromagnet
(D) Braking magnet
13. Torque on the disc of energy meter is produced due to
(A) Current coil of the meter
(B) Both current & pressure coils
(C) Pressure coil of the meter
(D) Permanent magnet
14. Purpose of using a permanent magnet in a single phase energy meter is
(A) To produce driving torque
(B) To produce braking torque
(C) To prevent the disc from external magnetic field
(D) To help the disc to start rotation
15. Energy meter is basically a ________ meter with counting mechanism
(A) Watt meter
(B) Ampere meter
(C) Volt meter
(D) KWH meter
16. This type of registering mechanism is used in energy meters
(A) Pointer type
(B) Cyclometer type
(C) Both a & b
(D) None of a & b
17. Current coil of energy meter is connected with
(A) Supply
(B) Between supply and load
(C) Load
(D) Parallel of the supply
18. If disc of energy meter rotates slowly without load, this error is called
(A) Friction error
(B) Speed error
(C) Frequency error
(D) Creeping error
19. The reason of creeping error in energy meters
(A) Supply voltage is more than standard
(B) Any of these
(C) Vibration
(D) Any external magnetic field
20. To eliminate the creeping error of energy meters
(A) Braking magnet is used
(B) Two holes are made on the opposite side of the disc
(C) Pressure coil of meter is removed
(D) Current coil is opened for the time being
21. To check the registration error of energy meter, this test is performed
(A) Long period test
(B) Both a & b
(C) Creep test
(D) Short period test
22. During creep test, load is removed and it is given
(A) 10 % more than the rated supply voltage
(B) Rated supply voltage
(C) 20 % more than the rated supply voltage
(D) 02 % more than the rated supply voltage
23. The purpose of phantom load test of energy meter is
(A) Saving of energy
(B) Both a & b
(C) Saving of time
(D) None of these
24. If percentage of error in energy meters is more than this then it is not usable
(A) 01 %
(B) 05 %
(C) 03 %
(D) 02 %
25. During the low power factor test, energy meter is loaded with rated load having power factor
(A) 0.9 lagging
(B) 0.7 lagging
(C) 0.4 lagging
(D) 0.5 lagging
26. Three phase induction type energy meters have
(A) Single element
(B) Double element
(C) Triple element
(D) Any of these
27. A single element poly phase meter has
(A) 01 disc, 01 pressure and 01 current coil
(B) None of these
(C) 02 disc, 01 pressure and 01 current coil
(D) 01 disc, 02 pressure and 02 current coil
28. Number of connection terminals in a three phase three wire double element energy meter are
(A) 03
(B) 06
(C) 04
(D) 07
29. Number of connection terminals in a three phase four wire triple element energy meter are
(A) 07 or 08
(B) 05 or 06
(C) 06 or 07
(D) 04 or 05
30. MDI is an abbreviation of
(A) Mutual double induction
(B) Maximum demand indicator
(C) Maximum dynamic intensity
(D) Moving drum indicator
31. MDI pointer moves when a consumer consumes the power more than its demand for
(A) 15 minutes to 30 minutes
(B) 05 Minutes
(C) 10 minutes
(D) 30 seconds
32. Number of pointers in indicating type MDI are
(A) 01
(B) 03
(C) 02
(D) None
33. All the MDIs are designed to record
(A) Momentary increase in power
(B) Permanent increase in power
(C) Increase in power for 30 minutes or more
(D) Both b or c