Volt drop is voltage lost due to inherent resistance in a cable.
Even though copper is a very good conductor, the wire itself still has some resistance, which over long cable runs can cause voltage to drop a lot.
Volt drop is also affected by ambient temperature. As temperature increases, so does the volt drop.
Standard voltage is 230 volts to earth.
Volt drop must be kept within 5% or 11.5 volts of 230 volts as per ASNZS:3000:2007. This means that voltage cannot go below 218.5 volts.
Volt drop is an important consideration that electricians must take when installing cables. If too much voltage is lost, it will damage appliances, especially motors and electronics.
The way to reduce volt drop is to reduce resistance. This is done by installing larger cables for larger loads and longer cable runs.
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