Identify the instrument that does not exist

(A) Dynamo-meter type ammeter (B) Dynamo-meter type wattmeter

(C) Moving-iron voltmeter (D) Moving-iron wattmeter

1 Answer

Answer :

Identify the instrument that does not exist

(A) Dynamo-meter type ammeter (B) Dynamo-meter type wattmeter

(C) Moving-iron voltmeter (D) Moving-iron wattmeter

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

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

Last Answer : 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 1.001 Ω

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Last Answer : The ratio of maximum displacement deviation to full scale deviation of the instrument is called linearity.

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