# Damping torque used in energy meter is : -

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Damping torque used in energy meter is : - a) Electrostatic b) Electro magnetic c) Eddy Current d) None

Damping torque used in energy meter is : - Eddy Current

## Related questions

For controlling the vibration of the disc of ac energy meter, damping torque is produced by

The disc of a single phase Induction-type energy meter makes 60 revolutions in 6 minutes. Meter Constant is 1200 rev/kWh. Power consumption in the load is (A) 1.2 kW (B) 1 kW (C) 600 W (D) 500 W

In a single phase induction energy meter, in order to obtain true value of energy, the shunt magnetic flux should lag behind the applied voltage by   (a) 90o (b) 0o (c) 45o (d) 60o

State the function and shape of following parts used in induction type energy meter: i) Series magnet ii) Shunt magnet iii) Al disc iv) Brake magnet

The best and efficient damping in Analog instruments is : - a) Air Friction damping b) Fluid Friction damping c) Eddy Current damping d) None of the above

In the time response analysis of control system, Damping Ratio is given by - a) Actual damping / Critical damping b) Critical damping /Actual damping c) ( Sum of the Actual damping and critical damping) /Actual damping d)( Difference of the Actual damping and critical damping) / critical damping

Energy meter runs slowly even if power is not used. This error is called (a) Speed error (b) Phase error (c) Creeping error (d) None of these

Phantom loading for testing of energy meter is used (A) to isolate the current and potential circuits (B) to increase power loss during testing (C) for meters having low current ratings (D) to test meters having a large current rating for which loads may not be available

In a flux meter, the controlling torque is _____.

In a particular meter, the deflecting torque is directly proportional to the current flowing through it, the type of meter is (a) moving coil (b) moving iron (c) induction (d) electro-static

The meter which does not have any component in it to provide control torque is (A) Electrodynamometer for current measurement (B) Electrodynamometer for voltage measurement (C) Electrodynamometer for power measurement. (D) Electrodynamometer for power factor measurement.

In an induction type energy meter, the steady speed attained by the rotating disc is  1. Proportional to the deflecting torque. 2. Proportional to the resistance of the path of eddy currents. 3. Inversely proportional to the effective readings of disc from its axis. 4. Inversely proportional to the square of brake magnet flux.  Which of the above are correct ?

The major cause for creeping in energy—meter is:  (1) Over compensation for friction (2) Vibrations (3) Stray magnetic fields (4) Excessive voltage across the potential coil

If an energy meter disc makes 10 revolutions in 100 seconds when a load of 450W is connected to it, the meter constant in revolutions per kWh is  A) 1000 B) 500 C) 1600 D) 800

Copper shading is provided in energy meter to  (A) Bring flux exactly in quadrature with applied voltage (B) To increase speed of aluminium disc (C) To count the rotation (D) To balance the system from vibration

Eddy current damping is normally used in the instruments of (a) Induction type (b) Moving iron type (c) Permanent magnet moving coil type (d) Nothing can be said

The damping winding in synchronous motor is generally used to?

A 0 -10 mAPMMC ammeter reads 5 mA in a circuit; its bottom control spring snaps out suddenly the meter will now read:- a) 5 mA b) 10 mA c) 2.5 mA d). 0

In a household single phase induction type wattmeter, the meter can be reversed by: - a) reversing the supply terminals b) reversing the load terminal c) opening the meter connection and reversing either the potential coil terminals or current coil terminals d) opening the meter and reversing the connection of both the potential coil terminals and current coil terminals

List the different methods to produce damping torque.

Ideally, the damping torque should be  (1) Proportional to velocity of the moving system and operating current.  (2) Proportional to the velocity of the moving system but independent of operating current.  (3) Independent of the velocity of the moving system and proportional to the operating current.  (4) Independent of the velocity of the moving system and operating current.

State the meaning of creeping error in 1 phase energy meter.

List any four errors in induction type energy meter. Give method of compensation for each.

An energy meter has a constant of 600 rev/kWh. If the meter makes 10 revolutions in 20 s, what is the load in kW?  (A) 0.75 kW (B) 1.5 kW (C) 3 kW (D) 6 kW

In moving iron instruments, eddy current damping cannot be used as  (a) They have a strong operating magnetic, field (b) They are not normally used in vertical position (c) They need a large damping force, which can only be provided by air friction (d) The introduction of a permanent magnet required for eddy current damping would distort the existing weak operating magnetic field

In the snubber circuit used in a thyristor to limit the peak voltage overshoot applied across it damping ratio is taken as about  A) 0.14 B) 0.21 C) 0.36 D) 0.62

Which one of the following frequency meter is suitable for measuring radio frequency?   (a) Vibrating reed frequency meter (b) Weston frequency meter (c) Electrical resonance frequency meter (d) Heterodyne frequency meter

A toothed type Tacho-generator has 60 teeth. A magnetic pickup is used in conjunction with it. The number of pulses generated per second in the magnetic pick up is : -  a) 3000 b) 1500 c) 1800 d) 1200

An aquadog is used in a 'CRO' to collect -  a) Secondary emission electrons b) Primary emission electrons c) Both Primary and Secondary emission electrons d) None of the above

Transformer coupling is used in class A amplifier to make it : -  a) more efficient b) less bulky c) less costly d) distortion free

In an electronic ohmmeter an op -amp is used as a: -  a) sommer b) multiplier c) buffer amplifier d) integrator

In a distortion factor meter, the filter at the front end is used suppress   (A) odd harmonics (B) even harmonics (C) fundamental component (D) dc component

What is meant by energy meter constant?

Why energy meter is integrating type measuring instrument?

The constant of a given energy meter is 500 revolution/kWh. At the test 4.4 kW full load, meter completes 50 revolutions in 86 seconds. The percentage error of the meter is (a) –4.86% (b) 4.86% (c) 2.0% (d) 3.0%

The disc of domestic supply energy meter is made of which material ? (a) Zinc (b) Copper (c) Aluminium (d) Silver

An induction type energy meter is found to run fast. Correction for this error can be made by  (A) Over-load compensation. (B) Voltage compensation. (C) Moving the brake magnet away from the centre of the disc. (D) Moving the brake magnet towards the centre of the disc.

A 200 V, 5 A d.c. energy meter is tested at its marked ratings. The resistance of the pressure circuit is 8000 Ω and that of current coil is 0.1 Ω. The power consumed when testing the meter with phantom loading with current circuit excited by a 6 V battery is (A) 2.5 W (B) 5 W (C) 32.5 W (D) 35 W