Wire Size For 30 Amp Circuit Breaker

The 30 amp is a standard ansi c73 13 tt 30p plug tt 30r receptacle.

Wire size for 30 amp circuit breaker.

If you are going by the nec using a copper conductor at the typical 75f sheathing material rating and using it in an environmentally controlled area then it would be 10awg per nectable 310 16 nec 2008 it s a new table number i. Wire gauge refers the physical size of the wire rated with a numerical designation that runs opposite to the diameter of the conductors in other words the smaller the wire gauge number the larger the wire diameter. This designation was made specifically for trailers. When plugged into a shore power using a single cable an rv turns into a single appliance.

These factors are what makes choosing the size of gauge wire to use for a 30 amp breaker not as straightforward as it seems. This article will explain how to wire a 30 amp rv breaker safely and adequately. The most common household item that requires a 30 amp circuit is a central air conditioner often people living in rvs use 30 and sometimes 50 amp systems to run all the appliances in the vehicle. 30 amp wire size for a maximum of 30 amps you ll need a wire gauge of 10.

Wire is sized by the american wire gauge awg system. The nec allows a maximum of a 3 voltage drop on the main branch of a circuit at the farthest outlet of power and 5 total to both feeders and branch circuits to the farthest outlet. From the chart above a 10 gauge copper wire with an ambient temperature rating of 60 or 140 is seen as standard in most conditions. Calculations the calculator uses the following formulas for calculating wire size which are based on ohm s law.

For example a 30 amp circuit breaker will trip at 30 amp no matter if is it continuous or non continuous load. It uses a 120 volt current. That s why we must select 20 25 higher size of current for circuit breaker than the flowing current in the cables and wires to the connected device. The 30 amp service for an rv is 120 volt with a 3 prong receptacle and a single 30 amp dedicated breaker.

Breaker size wire size based on copper thhn wire increase one size when using aluminum conductors at 115 volts at 230 volts 15 amp 14 1 380 2 760 20 amp 12 1 840 3 680 30 amp 10 seldom used on 115 voltage 5 520 40 amp 8 seldom used on 115 voltage 7 360 50 amp 6 seldom used on 115 voltage 9 200 60 amp 6 seldom used on 115 voltage.