100 amp sub panel wire size copper code#

This size of wire can carry more electricity than 8AWG and will also reduce the amount of voltage drop on the circuit.įurthermore, this size of wire can be used for both long-distance runs as well as short distances. Wire Sizesįor longer wire runs, it is best to use 6AWG aluminum wire. If it is longer than 50 feet, then you will need bigger wire like 6AWG. The NEC has rules that tell you the size of wire you need based on the length.įor example, if you have 8AWG aluminum wire and it is less than 50 feet long, then it can carry 100 amps. When using aluminum wire, it is important to check how much electricity it can carry. Therefore, a wire size of 8AWG would be suitable for a 100-amp sub panel. This means that the wire size should be selected such that it can carry 80% of the rated current of the breaker, which in this case is 100 amps.

100 amp sub panel wire size copper code#

The National Electric Code (NEC) recommends an 80% load capacity for subpanels. When selecting the correct wire for a 100-amp sub panel, you must consider two important things: ampacity and voltage drop.Īmpacity is the maximum amount of current that can be safely carried by the wire, while voltage drop is the difference in voltage between two points on an electrical circuit.ġ00 Amp Wire Breaker Size With 80% NEC Requirement

The number and size of the wires in the feeder cable depends on the current capacity of the subpanel, which must be at least equal to that of the main panel. This cable is made of two or more insulated wires, which are surrounded by an outer protective jacket. The subpanel contains a main breaker, which allows you to turn on or off the entire subpanel at once, as well as individual circuit breakers for each of the circuits in the subpanel.Ī subpanel is usually connected to a main service panel with a feeder cable. This cable goes from the main panel to the subpanel. The main circuit breaker sends some electricity to the subpanel through a thick cable called a feeder cable. It helps to provide more power and extra space.