What is the function of a voltmeter? A voltmeter is an instrument used for measuring the voltage or potential difference between two points in an electrical circuit. The voltmeter is always connected parallel. The voltmeter is of two types: digital voltmeter and analog voltmeter. In an analog voltmeter the pointer moves on the scale in proportion to the potential difference between the two points of the circuit. The digital voltmeter shows the voltage in numerical, it has an analog to digital converter.
Some of the voltmeters are designed to be used in DC circuits, others are manufactured for AC circuits. Voltmeter works on the principle of Ohm’s law.