Function of Wattmeter
- We have to measure electric power to know how much power any device or apparatus is drawing from the line.
- A wattmeter registers watts or kilowatts, and by reading it one can tell how much power any piece of apparatus is consuming.
- The amount of electric power delivered by a circuit depends on the amperes flowing and the volts of pressure.
- The meter must be connected so that the entire load current flows through it and the voltage pressure is across it.
- A wattmeter is essentially a combination of two instruments, an ammeter and a voltmeter. It has an ammeter coil of low resistance, which is connected into the circuit, and a voltmeter coil of high resistance, which is connected across the circuit.
- A wattmeter will have four terminals or binding posts, two for the currentcoil leads and two for the voltage-coil leads.