An induction wattmeter can be used for?

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Answer :

An induction wattmeter can be used for A.C. 

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Related questions

The torque produced in wattmeter is proportional to

Description : The torque produced in wattmeter is proportional to

Last Answer : A

In a 3-phase power measurement by two wattmeter method the reading of one of the wattmeter was zero...

Description : 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?

Last Answer : 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 0.5.

In a 3-phase power measurement by two wattmeter method, both the wattmeters had identical readings...

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

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

In a low power factor wattmeter the compensating coil is connected?

Last Answer : In a low power factor wattmeter the compensating coil is connected in series with pressure coil.

In a low power factor wattmeter the pressure coil is connected?

Last Answer : In a low power factor wattmeter the pressure coil is connected to the load side of the current coil.

The pressure coil of a wattmeter should be connected on the supply side of the current coil when?

Last Answer : The pressure coil of a wattmeter should be connected on the supply side of the current coil when load impedance is high.

A dynamometer wattmeter can be used for?

Last Answer : A dynamometer wattmeter can be used for both D.C. and A.C.

The resistance in the circuit of the moving coil of a dynamometer wattmeter should be?

Last Answer : The resistance in the circuit of the moving coil of a dynamometer wattmeter should be high.

Use Voltmeter, ammeter, wattmeter to determine active, reactive and apparent power consumed in given R-L series circuit, draw phasor diagram.

Description : Use Voltmeter, ammeter, wattmeter to determine active, reactive and apparent power consumed in given R-L series circuit, draw phasor diagram.

Last Answer : Practical Significance In the industry environment Electrical Engineering diploma graduate are expected to measure basic parameters like voltage, frequency, time period etc. for R-L series circuits. Therefore ... /varying L. 7. Draw the phasor diagram for each of reading for verification.

State the principle of wattmeter.

Description : State the principle of wattmeter. 

Last Answer : Working Principle of Wattmeter: It consists of two stationary coils, called current coils and one moving coil, called voltage or potential coil. The current coils are connected such that they ... experiences a force and tends to move in the direction as per Fleming's left hand rule. 

Merits of two wattmeter method

Description : Merits of two wattmeter method

Last Answer : Advantages of Two Wattmeter Method for 3-Phase Power Measurement: 1) It is used for balanced as well as unbalanced load. 2) For the star type load, it is not necessary to ... reactive volt-amperes for balanced loads also. 7) The circuit connections are independent of load connection.

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

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

Last Answer : Errors in wattmeter:  i) pc - inductance: Pressure coil inductance causes wattmeter to read more power than actual .  ii) pc-capacitance: The wattmeter reads less power.  iii) ... iv) Connection: In uncompensated wattmeter , the reading of wattmeter includes the powerloss in coils. 

State any four errors that occur in dynamometer type wattmeter

Description : State any four errors that occur in dynamometer type wattmeter

Last Answer : Errors that occur in dynamometer type wattmeter: 1. Errors due to method of connection. 2. Error due to pressure coil inductance. 3. Error due to pressure coil Capacitance. 4. Error due to mutual ... Error due to eddy currents. 7. Temperature error. 8. Error due to vibration of moving system

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

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

Last Answer : Particulars Current coil (CC) Pressure coil (PC) Connection Connected in series with load Connected in parallel with load Status It is fixed coil in wattmeter It is moving coil in ... number of turns It is having more number of turns Gauge of wire Less More

With neat diagram explain constructional details of dynamometer type wattmeter.

Description : With neat diagram explain constructional details of dynamometer type wattmeter.

Last Answer : Working Principle of Wattmeter: It consists of two stationary coils, called current coils and one moving coil, called voltage or potential coil. The moving coil is mounted on the spindle, in the gap ... experiences a force and tends to move in the direction as per Fleming's left hand rule. 

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

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

Last Answer : State any two disadvantages of one wattmeter method of measurement of 3 phase power. Disadvantages of one wattmeter method:- 1. Only used for balanced load 2. It can not be used for ... connection then neutral point must be available 4. Delta connection must be opened to connect current coil.

State various types of errors in wattmeter.

Description : State various types of errors in wattmeter.

Last Answer : Types of Error in wattmeter: 1. Errors due to method of connection. 2. Error due to pressure coil inductance. 3. Error due to pressure coil Capacitance. 4. Error due to mutual inductance effect. 5. ... . Error due to eddy currents. 7. Temperature error. 8. Error due to vibration of moving system.

Explain construction & working of electrodynamometer type wattmeter.

Description : Explain construction & working of electrodynamometer type wattmeter.

Last Answer : Electrodynamometer Type Wattmeter:  Construction: It essentially consists of the fixed and moving coil. The fixed coil is split into two equal parts which are placed close together and parallel to each other. ... hence these instruments can be used for measurement of A.C. & D.C. power.

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

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

Last Answer : Errors in Wattmeter Compensation method Error due to connection method To overcome this error, wattmeters are provided with additional compensating winding which is connected in series with ... due to friction The weight of moving system be reduced to minimum possible.

List one advantage and one disadvantage of one wattmeter method.

Description : List one advantage and one disadvantage of one wattmeter method. 

Last Answer : Advantages:  1) Only one wattmeter is used.  2) Less number of connections.  3) Cost required is less.  Disadvantages:  1) Used only for 3- Φ balanced load and not for ... be accessible for connecting the Pressure coil.  3) Delta connection must be opened to connect current coil. 

The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is

Description : 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%

Last Answer : 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 11%

An induction type energy meter is found to run fast. Correction for this error can be made by

Description : 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.

Last Answer : An induction type energy meter is found to run fast. Correction for this error can be made by Moving the brake magnet away from the centre of the disc.

Induction type single phase energy meters measure electric energy in?

Last Answer : Induction type single phase energy meters measure electric energy in kWh.

For handling greater currents induction wattmeters are used in conjunction with?

Last Answer : For handling greater currents induction wattmeters are used in conjunction with current transformers.

An induction meter can handle current up to?

Last Answer : An induction meter can handle current up to 100 A.

SINGLE PHASE INDUCTION MOTORS MCQ

Description : SINGLE PHASE INDUCTION MOTORS MCQ

Last Answer : 101. After the starting winding of a single phase induction motor is disconnected from supply, it continues to run only on (a) running winding (b) rotor winding (c) field winding (d) compensating winding Ans: a ... motor is usually reduced by using (a) gearing (b) belts (c) brakes (d) chains Ans: a

THREE PHASE INDUCTION MOTORS MCQ

Description : THREE PHASE INDUCTION MOTORS MCQ

Last Answer : 101. Insertion of resistance in the stator of an induction motor (a) increases the load torque (b) decreases the starting torque (c) increases the starting torque (d) none of the above Ans: b

Explain the working principle of induction motor.

Description : Explain the working principle of induction motor. 

Last Answer : Working principle of induction motor: * When the motor is excited with three-phase supply, three-phase stator winding carries three-phase currents & produces a rotating magnetic field of constant magnitude and ... , which tend to move the rotor in the same direction as the rotating magnetic field. 

Explain the activities carried out during weekly maintenance of 3 ph. Induction motor.

Description : Explain the activities carried out during weekly maintenance of 3 ph. Induction motor. 

Last Answer : Activities Carried out During Weekly Maintenance of 3 ph. Induction Motor:  1) Check belt tension. In cases where this is excessive it should immediately be reduces and in the case of sleeve ... and cooled by oil mist systems its important to check the oil mist flow paths/pressure components.

State the function of following parts in Induction motor. (i) Stator (ii) Slip rings

Description : State the function of following parts in Induction motor. (i) Stator (ii) Slip rings

Last Answer : Name of part Function Stator 1) Stator frame supports the core, terminal box and protects the inner parts. 2) Stator core houses stator winding. 3) Stator winding ... ) Provides facility to connect external resistance to rotor circuit through brushes for starting and control.

Electro Magnetic Induction

Description : Electro Magnetic Induction

Last Answer : Electro Magnetic Induction

List the energy conservation technique in induction motor.

Description : List the energy conservation technique in induction motor. 

Last Answer : Following are the list of energy conservation techniques in electrical motors: 1) Reduction in iron losses by using low loss silicon steel core material laminated to thinner dimension. 2) Using bigger length ... at light load. 13) By rewinding in induction motor 14) By motor survey

With a neat sketch give the working of shaded pole induction motor.

Description : With a neat sketch give the working of shaded pole induction motor.

Last Answer : Explanation: It has squirrel cage rotor and salient pole stator. The stator poles are shaded partially by short circuited conductor band to create the phase difference between the fluxes emerging from shaded ... rotating magnetic field in the air-gap and torque is exerted on the squirrel cage rotor.

What will happen if the induction motor runs at synchronous speed ?

Description : What will happen if the induction motor runs at synchronous speed ?

Last Answer : Since there is always slip present in rotor it cannot run at synchronous speed no current will be developed hence no torque will developed

Define Slip of Induction Motor.

Description : Define Slip of Induction Motor.

Last Answer : Slip: It is the ratio of relative speed of rotor (difference between synchronous speed and rotor speed) to the synchronous speed of rotating magnetic field.  Slip = (NS – N) / NS  where , NS = synchronous speed, N = speed of rotor

Enlist any four advantages of induction heating.

Description : Enlist any four advantages of induction heating. 

Last Answer : Advantages of Induction heating https://youtu.be/RcdH_74VJz0

Explain the working of a single phase capacitor start induction motor.

Description : Explain the working of a single phase capacitor start induction motor. 

Last Answer : Single phase capacitor start induction motor https://youtu.be/31lvvzU5Puc

State any four advantages of three phase induction motor.

Description : State any four advantages of three phase induction motor. 

Last Answer : Advantages of three phase induction motor https://youtu.be/27OIOCKN05U

With a neat diagram explain doubly fed induction generator (DFIG).

Description : With a neat diagram explain doubly fed induction generator (DFIG). 

Last Answer : Diagram of Doubly fed induction generator (DFIG):  Explanation :-  DFIG can feed power through the stator as well as rotor to the grid. The stator is directly connected to the fixed frequency ... voltage is 690 V AC. So it must be step up to 33 KV to connect to power grid.  

Explain Squirrel Cage Induction Generator (SCIG) and also draw a diagram.

Description : Explain Squirrel Cage Induction Generator (SCIG) and also draw a diagram. 

Last Answer : Explanation (Operation):- In this system gearbox is used to increase the speed of high speed shaft as per design. IG require reactive power for excitation. Rotor of SCIG is ... , variable voltage output of the generator into the fixed frequency, fixed voltage output required for grid. 

Explain energy conservation technique in induction motor by minimizing idle and redundant running of motor.

Last Answer : Energy conservation technique in induction motor by minimizing idle and redundant running of motor: 1) Loss of energy as the no load power drawn is approximately about 12% to 16% of rated ... to unnecessary line losses. 4) Reduction in overall system energy efficiency over period of time.

State and explain any four factors governing selection of induction motor.

Description : State and explain any four factors governing selection of induction motor.

Last Answer : The factors governing the selection of Induction motor: 1) Load torque required at normal speed matches with available torque of motor. 2) Break down torque or pull out torque or maximum torque ... If selecting energy efficient motor the cost benefit analysis over the long run must be worked out.

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

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

Last Answer : Energy conservation method in induction motor by improving power quality: Electrical energy can be conserved by improving the power quality. It can be achieved by avoiding voltage unbalance, maintaining ... losses can be minimized by using harmonic filter thus reducing the harmonics in the system.

Split phase induction motor

Description : Split phase induction motor

Last Answer : Split phase induction motor : There are two windings used in split phase induction motor. It is a type of single-phase induction motor. There are two winding one is called main winding and ... motor have low starting torque it is used for small fans, blowers, centrifugal pumps, grinders etc.

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

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

Last Answer : Name the starters used for following motors : i) 3 H.P. 3-Ph squirrel cage I.M: i) DOL starter OR ii) Star-Delta Starter OR ii) Auto transformer starter OR iii) Soft start starter.  ii) D.C Shunt Motor : 1) Armature resistance starter (Three Point Starter) OR 2) Four Point Starter 

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

Description : 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

Last Answer : i) Series magnet: produce flux proportional to current (load current) of circuit and interact in the aluminum disc with flux produced by voltage magnet for torque production. Its shape is like letter U.  ii) ... : brakes the motion of the aluminum disc or slows it down. Its shape is like letter C. 

Draw a neat sketch of 1-ph induction type energy meter and write operating principle of it.

Description : Draw a neat sketch of 1-ph induction type energy meter and write operating principle of it. 

Last Answer : Operating Principal:- The disc is placed between the two-flux due to pressure coil and flux due to current coil, which will set up torque on the disc which is proportional to power causing the ... is proportional to voltage, the second carries a current coil so its flux is proportional to current.

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

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

Last Answer : Errors in Induction Type Energy Meter with their Compensation:  1) Error due to friction: This error can be compensated by the additional shading band provided on the shunt electromagnet.  2) Phase ... error: This error can be compensated by providing a flux diverter' to the current magnet. 

In a double squirrel cage induction motor, good starting torque is produced as

Description : In a double squirrel cage induction motor, good starting torque is produced as (A) Large current flows through the outer high resistance winding. (B) Large current flows through the inner high ... the outer high resistance winding. (D) Large current flows through the inner low resistance winding.

Last Answer : In a double squirrel cage induction motor, good starting torque is produced as Large current flows through the outer high resistance winding.

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

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

Last Answer : A change of 4% in the supply voltage to an induction motor will produce a change of approximately 8% in the rotor torque