Voltmeter and Ammeter

VOLTMETER

A voltmeter is connected parallely to the circuit or branch where the differences in the potentials of the two points needs to be measured. Due to high resistance very low amount of current flows through its high internal resistance. According to Ohm’s Law — V = I*R; the potential difference is measured.

Precisely, the amount of current flows through the internal resistance helps to give the deflecting torque to the pointer of a typical Analogue Voltmeter and the scale reads, some Power electronics equipment are also used for Digital meters.

AMMETER

An ammeter is connected in series with the branch and the amount of current flows inside the ammeter deflects the pointer. It has less internal resistance.