Measured in Volts.
Voltage can be explained as the electrical ‘pressure’ that pushes current.
Voltage consists of the difference in ‘electrical pressure’ between two points. E.g – your hand touching a live wire and your feet touching earth.
The ‘electrical pressure’ between the phase and earth is 230 volts (different in other countries). As voltage increases, the strength of wire insulation needs to increase.
Voltage is affected by how much resistance is in a circuit. If resistance is too high (such as a long cable run or using a too small cable), then voltage is lost (known as volt drop).
Voltage drop must not exceed 5% or 11.5 volts for single phase (ASNZS:3000:2007 section 3.6)
An electrician’s job is to ensure that voltage is not dropped by more than this amount. Voltage is measured with a voltmeter or a multimeter.
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