Question

An electrical engineering student is assigned to measure power consumed by a single phase 220 VAC load. With the help of illustrations, explain the two possible ways he/she could accomplish the task if he only has ammeters, voltmeters VT, CT Megga, Zero adjustable ohmmeter, VAR-meter in the workshop.

Answer 1

Given that we have 220v AC supply and the load is given.

1st method

We have one ammeter and one voltmeter, ammeter is connected in series with the load and voltmeter is connected across the load we can get the ammeter and voltmeter readings.In order to get the power consumed by the load we will multiply the both reading of ammeter and voltmeter which gives the power consumed by the load.

2nd method

As we have ohmmeter we can measure the resistance of the load and from the voltmeter we can get the voltage across the load.

Power consumed=V^2/R