Draw and describe working of electronic energy meter.

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Answer :

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working of electronic energy meter:- 1. CT reduces current to reasonable value for current scaling network. 2. Voltage & current scaling networks reduce proportionally the voltage & current to values suitable for the analog multiplier. 3. Analog multiplier gives a dc voltage proportional to the product of the voltage and current drawn from supply that is the power drawn. 4. The voltage controlled oscillator gives a frequency proportional to its input (which is proportional to the power). 5. The ADC converts the square wave frequency analog output to display the energy in watthour. 

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