Permanent magnet moving coil instruments are used for

Permanent magnet moving coil instruments are used for
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2 Answers

Answer :

Permanent magnet moving coil instruments are used for DC 

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Answer :

PMME are mostly used for measuring voltage and current.
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Related questions

Name the material used for :- (i) Moving coil (ii) Permanent magnet in PMMC instrument.

Description : Name the material used for :- (i) Moving coil (ii) Permanent magnet in PMMC instrument.

Last Answer : (i) Material used for Moving coil: Copper, Aluminum( some times)  (ii) Permanent magnets are made of special alloys such as :  Aluminum-Nickel-Cobalt (Alnicos)  Strontium-Iron  Neodymium-Iron-Boron  Samarium-Cobalt.

A moving-coil permanent-magnet instrument can be used as flux-meter?

Last Answer : A moving-coil permanent-magnet instrument can be used as flux-meter by eliminating the control springs.

A moving-coil permanent-magnet instrument can be used as what by using a low resistance shunt?

Last Answer : A moving-coil permanent-magnet instrument can be used as ammeter by using a low resistance shunt.

When the voltage across a battery is measured using a D.C potentiometer, the reading shows 1.08 V. But

Description : When the voltage across a battery is measured using a D.C potentiometer, the reading shows 1.08 V. But when the same voltage is measured using a Permanent Magnet Moving Coil (PMMC) voltmeter, the voltmeter reading shows 0.99 ... resistance of the battery, in Ohm , is (A) 150 (B) 100 (C) 50 (D) 200

Last Answer : When the voltage across a battery is measured using a D.C potentiometer, the reading shows 1.08 V. But when the same voltage is measured using a Permanent Magnet Moving Coil (PMMC) voltmeter, ... resistance of the voltmeter is 1100 Ohm , the internal resistance of the battery, in Ohm , is 100

State the material used for moving coil and former for PMMC instruments.

Description : State the material used for moving coil and former for PMMC instruments. 

Last Answer : Material Used for Moving Coil and Former for PMMC Instruments:  Material used for moving coil: Copper  Material used for Former: Aluminium

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Description : Compare variable reluctance and permanent magnet motors.

Last Answer : Variable reluctance Motor  Permanent magnet motors   The rotor is not magnetised The rotor is magnetised  High torque to inertia ratio  Low torque to inertia ratio  ... rotor has salient pole construction The rotor has mostly smooth cylindrical type of construction. 

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Description : What is permanent magnet and electromagnet?

Last Answer : Permanent magnet: A permanent magnet is an object made from a material that is magnetized and creates its own persistent magnetic field. As the name suggests, a permanent magnet is 'permanent'. ... an electric current passes through the coil. If the current is interrupted, the magnetism is lost.

A neodymium magnet is a permanent magnet made from an alloy of _________

Description : A neodymium magnet is a permanent magnet made from an alloy of _________ A) Neodymium and iron B) Neodymium, iron and iodine C) Neodymium and boron D) Neodymium, iron and boron

Last Answer : A neodymium magnet is a permanent magnet made from an alloy of Neodymium, iron and boron

A moving coil of meter has 100 turns, and a length and depth of 10mm and 20mm respectively. It is positioned

Description : A moving coil of meter has 100 turns, and a length and depth of 10mm and 20mm respectively. It is positioned in a uniform radial flux density of 200 mT. The coil carrier current capacity is 50 mA. The torque on the coil is

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Commonly used instruments in power system measurement are?

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A moving coil meter has a resistance of 3 Ω and gives full scale deflection with 30 mA. To measure voltage up

Description : A moving coil meter has a resistance of 3 Ω and gives full scale deflection with 30 mA. To measure voltage up to 300 V, the external resistance to be connected in series with the instrument is (A) 9997 Ω (B) 10000 Ω (C) 997 Ω (D) 10003 Ω

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Peterson coil is used for :

Description : Peterson coil is used for :  (A) shunt compensation of lines (B) grounding of system neutral (B) reduce fault currents (D) connecting interconnected systems

Last Answer : Peterson coil is used for : grounding of system neutral

An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic

Description : An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be  (1) unaffected (2) decreased (3) increased (4) either decreased or increased depending on the direction of the DC field

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Description : Eddy current damping cannot be used for moving iron instrument because

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The self inductance of a coil can be measured using

Description : The self inductance of a coil can be measured using (A) Wien’s Bridge (B) Schering Bridge (C) Anderson’s Bridge (D) Wheatstone Bridge

Last Answer : The self inductance of a coil can be measured using Anderson’s Bridge

A PMMC instrument has FSD of 100 μA and a coil resistance of 1 kΩ. To convert the instrument into an

Description : A PMMC instrument has FSD of 100 μA and a coil resistance of 1 kΩ. To convert the instrument into an ammeter with full scale deflection of 100 mA, the required shunt resistance is (A) 1 Ω (B) 1.001 Ω (C) 0.5 Ω (D) 10 Ω

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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 multiplier and the meter coil in a voltmeter are in?

Last Answer : The multiplier and the meter coil in a voltmeter are in series.

The use of _____ instruments is merely confined within laboratories as standardising instruments.

Description : The use of _____ instruments is merely confined within laboratories as standardising instruments.

Last Answer : The use of absolute instruments is merely confined within laboratories as standardizing instruments.

Operating torques in analogue instruments are?

Last Answer : Operating torques in analogue instruments are deflecting, control and damping.

The power factor of a single phase load can be calculated if the instruments available are?

Last Answer : The power factor of a single phase load can be calculated if the instruments available are three ammeters or three voltmeters.

The switch board instruments?

Last Answer : The switch board instruments should be mounted in vertical position.

In majority of instruments damping is provided by?

Last Answer : In the majority of instruments, damping is provided by eddy currents.

According to application, instruments are classified as?

Last Answer : According to application, instruments are classified as switch board, portable.

The use of which instruments is merely confined within laboratories as standardizing instruments?

Last Answer : The use of absolute instruments is merely confined within laboratories as standardizing instruments.

What do you mean by secondary instruments?

Description : What do you mean by secondary instruments?

Last Answer : The instruments which will give the direct readings are called secondary instruments

Hard steel is suitable for making permanent magnets because?

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Those materials are well suited for making permanent magnets which have _____ retentivity and _______ coercivity.

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Last Answer : Those materials are well suited for making permanent magnets which have high retentivity and high coercivity.

Permanent magnets are normally made of?

Description : Permanent magnets are normally made of?

Last Answer : Permanent magnets are normally made of alnico alloys.

A permanent magnet moving coil ammeter has a coil resistance of 99 ohm and Full Scale Deflection (FSD)

Description : A permanent magnet moving coil ammeter has a coil resistance of 99 ohm and Full Scale Deflection (FSD) current of 0.1mA. Shunt resistance is 1 ohm. Current through the meter at 0.5 F.S.D is:

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Description : State the function of overload coil and No volt coil in dc motor starter.

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The purpose of the restraining coil in a biased differential relay is

Description : The purpose of the restraining coil in a biased differential relay is  (A) To reduce CT saturation during fault.  (B) To increase the sensitivity of the relay.  (C) To match the transformation ratio.  (D) To limit the spill current through the relay during heavy external fault.

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lt the length, number of turns and area of a coil are doubled, the inductance of the coil

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Last Answer : lt the length, number of turns and area of a coil are  doubled, the inductance of the coil is quadrupled

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

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Description : The rate of rise of current through an inductive coil is maximum?

Last Answer : The rate of rise of current through an inductive coil is maximum at the start of the current flow.

The inductance of a coil can be increased by?

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Inductance of coil?

Description : Inductance of coil?

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Inductance of a coil Varies?

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Armature coil is short circuited by brushes when it lies?

Last Answer : Armature coil is short circuited by brushes when it lies along neutral axis.

Open circuited armature coil of a D.C. machine is?

Last Answer : Open circuited armature coil of a D.C. machine is identified by the scarring of the commutator segment to which open circuited coil is connected and indicated by a spark completely around the commutator.

In a shaded pole motor, the shading coil usually consist of?

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Description : List of Scientific Instruments

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Description : Electrical Measuring Instruments

Last Answer : Electrical Measuring Instruments

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calibration and the need of calibration for measuring instruments.

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