# An induction wattmeter can be used for?

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An induction wattmeter can be used for A.C.

## Related questions

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.

The torque produced in wattmeter is proportional to

In a 3-phase power measurement by two wattmeter method the reading of one of the wattmeter was zero. The power factor of the load must be?

In a 3-phase power measurement by two wattmeter method, both the watt meters had identical readings. The power factor of the load was?

List the different errors in wattmeter & explain compensation for it.

The synchronous speed of an 8 pole induction motor supplied power from a 50 Hz source will be ?

State starters used for i) 3-Ph squirrel cage induction motor (3HP) ii) D.C. motor

Why starter is required for starting an induction motor?

Consider the following statements with regard to induction type wattmeter :  1. Can be used on both ac and dc systems.  2. Power consumption is relatively low.  3. It is accurate only at stated frequency and temperature.  Which of the above statements is/are correct ?  (a) 1 only (b) 2 only (c) 3 only (d) 1, 2 and 3

Merits of two wattmeter method

State the effects of errors in dynamometer type wattmeter due to i) pc- inductance ii) pc- capacitance iii) mutual inductance iv) Connection.

State any four errors that occur in dynamometer type wattmeter

Compare CC and PC of wattmeter on the basis of:- (i) Connection (ii) Status (iii) Number of turns (iv) Gauge of wire.

With neat diagram explain constructional details of dynamometer type wattmeter.

State any two disadvantages of one wattmeter method of measurement of 3 phase power.

State various types of errors in wattmeter.

Explain construction & working of electrodynamometer type wattmeter.

The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is (A) 11% (B) 9% (C) 1.1% (D) 3%

how can we reverse the direction of rotation of three phase induction motor ?

The rotor impedance of a slip ring induction motor is (0.1 + j0.6)Ohm/ ph . The resistance/ph to be inserted into rotor to get maximum torque at starting should be

The number of poles in a phase induction motor at 50 Hz and running at 1500 rpm will be?

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 range of frequencies used in induction heating is :  (A) 0-25 Hz  (C) less than 200 Hz  (B) 50 to 100 Hz  (D) more than 1 kHz

A change of 4% in the supply voltage to an induction motor will produce a change of approximately

In an induction motor if the flux density is reduced to one-half, of its normal value then the torque will  (1) reduce to one-half (2) reduce to one-fourth (3) remain unchanged (4) increase four times

An 8-pole, 50Hz, three-phase induction motor is running at 705rpm and has a rotor copper loss of 5kW. Its rotor input is (A) 5.06 kW (B) 0.3 kW (C) 100 kW (D) 83.33 kW

In a 3-phase slip-ring induction motor, the slip at some speed is 0.05. The speed is reduced by inserting an external resistance in the rotor circuit and the slip is 0.15. If the rotor winding resistance per phase is 0.2 Ω, the external resistance is (A) 0.2 Ω (B) 0.3 Ω (C) 0.4 Ω (D) 0.5 Ω

A synchronous motor has better power factor as compared to that of an equivalent induction motor. This is mainly because?

Explain energy conservation technique “by improving power quality” for induction motor.

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

A 400 V, 50 Hz three-phase induction motor rotates at 1440 rpm on full -load. The motor is wound for

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