Basic Electrical Engineering

Dynamometer Type Wattmeter

Dynamometer type Wattmeter:

Principle:  When a current carrying moving coil is placed in a magnetic field produced by the current carrying fixed coil, a mechanical force is exerted on the coil sides of the moving coil and deflection  takes place.

when the field produced by the current carrying moving coil(Fr) tries to come in line with the field produced by the current carrying fixed coil (Fm), a deflecting torque is exerted on the moving  system.

Principle:

Construction:

Working Principle: In case of AC system