State the working principle of PMMC Analog instrument.

State the working principle of PMMC Analog instrument.
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Answer :

Working Principal of PMMC Analog Instrument: When current carrying conductor is placed in a magnetic field, it experiences mechanical force. In PMMC instrument, when current flows through a coil placed in the gap between the poles, force is produced on the coil. The coil rotates and pointer attached to the coil shows deflection proportional to the current magnitude.
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Description : Controlling torque in PMMC

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role of the series resistance connected in PMMC movement.

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PMMC type instruments normally use

Last Answer : PMMC type instruments normally use Eddy current damping.