Voltage, measured in volts, is the electrical potential difference between two points in an electrical circuit. Checking for voltage is an important safety procedure to ensure that electrical circuits are operating correctly and to prevent electrical shock.
There are a few different ways to check for voltage, but the most common method is to use a voltmeter. A voltmeter is a device that measures the electrical potential difference between two points. To use a voltmeter, simply connect the positive lead of the voltmeter to the positive terminal of the circuit and the negative lead of the voltmeter to the negative terminal of the circuit. The voltmeter will then display the voltage in volts.