Postby TGTS0907129» Watthour meter

Describe Watthour meter


The watt-hour meter is a device of the measurement of electricity energy. This is the type of meter which is so commonly found in houses for indicating the amount of energy which has been furnished by the electric utility company. The electrodynamometer type of meter is basically a special type of motor revolves at a speed that is proportional to the power used. This is accomplished by having the field coils F and F’ of the motor connected in series with the load, thus producing a magnetic field that Is proportional to the current in the load. The armature is connected in parallel with the load, through a multiplying resistor R. hence its magnetic field is proportional to the voltage of the load. The resultant torque, being separately proportional to each of these fields, is therefore proportional to their produced and hence to the product of current and voltage, or the power. Suitable pointers geared to turn with armature, indicate on their respective dials the number of watt-hours (more often kilowatt-hours) used in the load. The aluminum disk D connected to the armature spindle rotates in the field of the magnets M and M’. the induced eddy currents thereby generated act as brake on the armature and provide a mechanism for adjusting the rate of the rotation when the magnets are moved toward or away from the disk in servicing the device.

By TGTT170912123 on 10/19/2015 3:41:40 AM
TGTS0907129 on 10/19/2015 3:40:05 AM

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