A.C. Induction Meter

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A. C. induction-type energy meters are the most common form of meters met within everyday domestic and industrial installations. These energy meters mes sure electric energy in kilowatt hours.(kw H). The principle of these meters. is practically the same as that of the induction watt meters. There are two varieties of induction-type a.c. energy meters: 

Single phase energy meters are used tonearm- sure electric energy. in a.c, single-phase circuits.

Operating Principle In a single-phase energy meter, rotation of the disc is produced by the eddy currents due to the binned fluxes of two electromagnets. The fluxes of these two magnets are kept 90° apart to make the rotating field. 

Construction Figure.

4.15 illustrates the different parts of a single-phase energy meter.  

It consists of a light aluminium disc mounted on a steel spindle pivoted on a jeweled bottom bearing and a pin-type top bearing. The disc is arranged to revolve in the air-gap between the poles of two electromagnets  one supplied with a current proportional to the voltage of the supply and the other with a current proportional to the main current of the circuit. The braking torque is produced by one or two permanent magnets inducing eddy currents in the disc.