The Three-Phase Wattmeter module is fitted with two separate wattmeters, each of which is equipped with a polarity switch. Its electronic design uses voltage and current sensors to sample line voltage and current. Voltage and current circuits are internally connected so that students only have to connect the “line” and “load” terminals of the module. The three-phase active power is the algebraic sum of the two meter indications. When used independently, each meter will indicate active power in single-phase circuits.