#Wire size for 100 amp breaker full

Standard lugs may only accept wires up to #4 AWG. Wire Lug TerminationsĪt the main service panel, use properly rated lugs for 3/0 AWG 100a copper wires. For the larger 3/0 AWG, specific 100A rated splicing products must be utilized. Many basic wire nuts only support #10 or #12 AWG wires. When splicing 100A copper wires, choose connectors listed for that size and amperage. Excessive voltage drop results in equipment problems, so keep wire distances within recommended limits. For example, use 2 AWG rather than 3/0 AWG. Voltage Drop Effectsįor long copper wire runs, upsizing one gauge size can help minimize voltage drop.

Properly sized wires prevent excessive heat buildup and damage from potential overload conditions. Using the standard 100a copper wire sizes like 3/0 AWG for service entrance conductors maintains the designed 100A ampacity rating. THHN withstands the high temperatures that can occur in a 100A circuit. For example, a #3 THHN wire supports 100A breakers, while #10 THHN wires work for 30A branch circuits. THHN is a common insulation type used on copper wires in conduit for 100A circuits.

The thicker gauge enables the grounding system to quickly clear any faults. This satisfies NEC standards for proper grounding up to a 100 amp service. The recommended 100a copper wire size for an effective grounding conductor at a 100A service size is #4 AWG. The thicker #3 wire prevents overheating from occurring on the branch circuit. This gauge meets NEC requirements for proper current carrying capacity on a 100 amp circuit. Branch Circuit Wire Sizeįor branch circuits supplied through a 100A circuit breaker, the minimum 100a copper wire size is #3 AWG. In some cases 1 AWG may be seen, but 3/0 AWG offers lower voltage drop. This properly sizes the 100A subpanel feeder wire based on the designed load in the subpanel. Where a 100A subpanel will be fed from the main panel, 3/0 AWG copper is the standard 100a copper wire size used.

#Wire size for 100 amp breaker full

The large diameter of 3/0 AWG enables safe passage of the full 100A current. This meets NEC minimum size requirements for a 100 amp service using copper wiring. For overhead and underground 100A service entrance conductors, the recommended 100a copper wire size is 3/0 AWG.