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

1 Answer

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) Shunt magnet: produce flux proportional to voltage of circuit and interact in the aluminum disc with flux produced by current magnet for torque production. It is in the form of three-limb core. Its shape is like letter E. 

iii) Aluminum disc: rotates due to interaction of fluxes by current & voltage magnet. Its shape is like circular lamina. 

iv) Brake magnet: brakes the motion of the aluminum disc or slows it down. Its shape is like letter C. 

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