The damping torque must operate only when the moving system of the indicating instrument is:

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The damping torque must operate only when the moving system of the indicating instrument is: Actually moving

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Related questions

For the indicating instrument the preferred damping condition is

Last Answer : For the indicating instrument the preferred damping condition is  a damping coefficient of 0.8 to 1.

As the deflection of the moving system increases, the controlling torque in an indicating instrument.

Description : As the deflection of the moving system increases, the controlling torque in an indicating instrument.

Last Answer : increases

A moving coil instrument is used as an ohmmeter. The indicating scale of the meter will be

Last Answer : A moving coil instrument is used as an ohmmeter. The indicating scale of the meter will be Hyperbolic.

Eddy current damping cannot be used for moving iron instrument because

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

Last Answer : Eddy current damping cannot be used for moving iron instrument because the presence of a permanent magnet required for such purpose would affect the deflection and hence the reading of the instrument

In a moving coil instrument, the deflecting torque is proportional to

Last Answer :  In a moving coil instrument, the deflecting torque is proportional to Current.

When both deflecting and controlling torque act, the pointer of an indicating instrument comes to

Description : When both deflecting and controlling torque act, the pointer of an indicating instrument comes to

Last Answer : rest

If the pointer of an indicating instrument is in motion, then what opposes deflecting torque?

Description : If the pointer of an indicating instrument is in motion, then what opposes deflecting torque?

Last Answer : damping and controlling torque

The pointer of an indicating instrument should be?

Last Answer : The pointer of an indicating instrument should be very light.

Ideally, the damping torque should be

Description : 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 ... operating current.  (4) Independent of the velocity of the moving system and operating current.

Last Answer : Ideally, the damping torque should be Proportional to the velocity of the moving system but independent of operating current. 

In a PMMC instrument, the damping provided is :

Description : In a PMMC instrument, the damping provided is :  (A) air damping (C) eddy current damping (B) fluid damping (D) magnetic damping using a magnet

Last Answer : In a PMMC instrument, the damping provided is : eddy current damping 

The disc of an instrument using eddy current damping should be of?

Last Answer : The disc of an instrument using eddy current damping should be of conducting and non-magnetic material.

In moving coil meters, damping is provided by

Last Answer : In moving coil meters, damping is provided by eddy current disk.

The effect of stray magnetic fields on the actuating torque of a portable instrument is maximum when the

Description : The effect of stray magnetic fields on the actuating torque of a portable instrument is maximum when the operating field of the instrument and the stray fields are  A) Perpendicular B) Parallel C) Inclined at 60" D) Inclined at 30°

Last Answer : The effect of stray magnetic fields on the actuating torque of a portable instrument is maximum when the operating field of the instrument and the stray fields are Parallel 

In a portable instrument, the controlling torque is provided by?

Last Answer : In a portable instrument, the controlling torque is provided by spring.

Which of the following statements regarding the use of a current measuring instrument is correct? A. It must be connected in series with the circuit. B. You should always start with the lowest range until a suitable reading is obtained. C. The indicating needle is deflected from left to right regardless of polarity. D. An external shunt is generally utilized where current is less than 10 amperes.

Description : Which of the following statements regarding the use of a current measuring instrument is correct? A. It must be connected in series with the circuit. B. You should always start with the lowest range ... of polarity. D. An external shunt is generally utilized where current is less than 10 amperes.

Last Answer : Answer: A

In a moving iron meter, the deflecting torque is proportional to

Last Answer : In a moving iron meter, the deflecting torque is proportional to Square of the current through the coil.

A moving coil instrument has a resistance of 10 W and gives full scale deflection when carrying

Description : A moving coil instrument has a resistance of 10 W and gives full scale deflection when carrying a current of 50 mA. To measure current upto 100 A, we will have to connect • 10 W resistance in series • 10 W resistance in parallel • 10/1999 W resistance in series • 10/1999 W resistance in parallel

Last Answer : A moving coil instrument has a resistance of 10 W and gives full scale deflection when carrying a current of 50 mA. To measure current upto 100 A, we will have to connect 10/1999 W resistance in parallel

In a dynamo-meter type of moving coil instrument a swamping resistance is provided in order to:

Last Answer : In a dynamo-meter type of moving coil instrument a swamping resistance is provided inorder to: Provide equal time constant for moving coil and fixed coil, when used for ac measurement

A moving iron instrument can be used for?

Last Answer : A moving iron instrument can be used for both D.C. and A.C.

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.

Coast Guard Regulations (46 CFR), require that an indicating light at the propulsion control station will operate if overloading or overheating occurs in a _______________. A. forced draft blower motor B. steering gear motor C. fuel pump motor D. condensate pump motor

Description : Coast Guard Regulations (46 CFR), require that an indicating light at the propulsion control station will operate if overloading or overheating occurs in a _______________. A. forced draft blower motor B. steering gear motor C. fuel pump motor D. condensate pump motor

Last Answer : Answer: B

The force required to move the pointer in an indicating instruments is

Description : The force required to move the pointer in an indicating instruments is

Last Answer : The force required to move the pointer in an indicating instruments is deflecting force

A rotary system has a damping coefficient of 40 N-m-sec/rad. The damping torque at a velocity of 2 rad/s, will be A) 20 N-m B) 40 N-m C) 80 N-m D) 100 N-m

Description : A rotary system has a damping coefficient of 40 N-m-sec/rad. The damping torque at a velocity of 2 rad/s, will be A) 20 N-m B) 40 N-m C) 80 N-m D) 100 N-m

Last Answer : C) 80 N-m

A control system having unit damping factor will give

Description : A control system having unit damping factor will give  (1) Oscillatory response (2) Undamped response (3) Critically damped response (4) No response

Last Answer : 1

The use of telecommunication for automatic indicating or recording measurement at the distance from the measuring instrument. A. Monitoring B. Tracking C. Telemetry D. Telecommand

Description : The use of telecommunication for automatic indicating or recording measurement at the distance from the measuring instrument. A. Monitoring B. Tracking C. Telemetry D. Telecommand

Last Answer : C. Telemetry

What are the essentials of indicating instrument?

Description : What are the essentials of indicating instrument?

Last Answer : a. Deflecting torque or force (effect of electricity). b. Controlling torque or force (spring control and gravity control). c. Damping torque or force (air friction, eddy current and fluid friction).

An indicating instrument whose movable coils rotate between two-stationary coils, usually used as wattmeter

Description : An indicating instrument whose movable coils rotate between two-stationary coils, usually used as wattmeter

Last Answer : electrodynamometer

A tunable RF instrument, which, by means of a sharp dip of an indicating meter, indicates resonance with an external circuit under test

Description : A tunable RF instrument, which, by means of a sharp dip of an indicating meter, indicates resonance with an external circuit under test

Last Answer : dip meter

What is the force acting on the pointer of an indicating instrument when it is in motion?

Description : What is the force acting on the pointer of an indicating instrument when it is in motion?

Last Answer : controlling, damping and deflecting torques

Indicating instrument is assumed to be most accurate at what part of the scale?

Description : Indicating instrument is assumed to be most accurate at what part of the scale?

Last Answer : at half or full

The pointer of an indicating instrument is generally made of

Description : The pointer of an indicating instrument is generally made of

Last Answer : aluminum

When a synchronous motor is running at synchronous speed, the damper winding produces (A) damping torque. (B) eddy current torque. (C) torque aiding the developed torque. (D) no torque.

Description : When a synchronous motor is running at synchronous speed, the damper winding produces (A) damping torque. (B) eddy current torque. (C) torque aiding the developed torque. (D) no torque.

Last Answer : (D) no torque.

List the different methods to produce damping torque.

Description : List the different methods to produce damping torque.

Last Answer : Methods of providing damping torque in indicating type instruments: 1) Air friction damping. 2) Fluid friction damping. 3) Eddy current damping.

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

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

Last Answer : For controlling the vibration of the disc of ac energy meter, damping torque is produced by Eddy current

Damping torque used in energy meter is : -

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

Last Answer : Damping torque used in energy meter is : - Eddy Current

Eddy current damping is normally used in the instruments of

Description : 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 

Last Answer : Permanent  magnetic  moving  coil  instrument.

Control systems are generally designed with damping

Description : Control systems are generally designed with damping  a) less than one  b) greater than one c) equal to one d) with any value depending upon system requirement

Last Answer : Control systems are generally designed with damping  less than one 

Air friction damping is used in the instruments which is:

Last Answer : Air friction damping is used in the instruments which is: Moving iron

Damping of the Ballistic galvanometer is made small to?

Last Answer : Damping of the Ballistic galvanometer is made small to get first deflection large.

In majority of instruments damping is provided by?

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

The most efficient form of damping in an instrument is

Last Answer : The most efficient form of damping in an instrument is Eddy current.

What does the torque switch mechanism senses to operate?

Description : What does the torque switch mechanism senses to operate? 

Last Answer : Torque switch senses whether the torque of motor has exceeded the set point irrespective of position of valve. 

To reverse the direction of rotation of a three-phase AC induction motor, do one of the following: w) reverse any two of the three-phase connections x) change the frequency of the applied AC power y) operate the motor below the stall torque at very high slip z) none of the above

Description : To reverse the direction of rotation of a three-phase AC induction motor, do one of the following: w) reverse any two of the three-phase connections x) change the frequency of the applied AC power y) operate the motor below the stall torque at very high slip z) none of the above

Last Answer : ANSWER: W -- REVERSE ANY TWO OF THE THREE-PHASE CONNECTIONS 

The meter which does not have any component in it to provide control torque is

Description : 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.

Last Answer : The meter which does not have any component in it to provide control torque is Electrodynamometer for power factor measurement.

The torque produced in wattmeter is proportional to

Description : The torque produced in wattmeter is proportional to

Last Answer : A

In a ballistic galvanometer, the deflecting torque is proportional to

Last Answer :  In a ballistic galvanometer, the deflecting torque is proportional to the current through coil.

In the case of PMMC rectifier type instruments, the deflecting torque is proportional to

Last Answer : In the case of PMMC rectifier type instruments, the deflecting torque is proportional to Average value of AC current.