Wire Gauge Amp Chart | PES Supply

Wire Gauge & Ampacity Chart

Complete AWG wire gauge ampacity chart for solar, battery, and generator installations. Find the right wire size for any current.

Formula

AWG Wire Gauge Ampacity Chart (Copper, 90°C)

AWG Ampacity Copper Area Common Uses
14 AWG 15A 2.08 mm² Lighting, small appliances
12 AWG 20A 3.31 mm² Standard outlets, small inverters
10 AWG 30A 5.26 mm² RV shore power, small solar
8 AWG 40A 8.37 mm² Solar panel arrays, charge controllers
6 AWG 55A 13.3 mm² Large solar arrays, inverter input
4 AWG 70A 21.2 mm² Battery banks, large inverters
2 AWG 95A 33.6 mm² Large battery banks, generator leads
1/0 AWG 150A 53.5 mm² Commercial solar, standby generators
2/0 AWG 175A 67.4 mm² Large commercial installations
4/0 AWG 230A 107 mm² Industrial solar, utility-scale

Solar Wire Sizing Guide

  • Always add 25% safety margin to your calculated current
  • For wire runs over 10 feet, increase wire size to reduce voltage drop
  • Use PV-rated wire (THWN-2 or USE-2) for outdoor solar installations
  • Battery interconnect cables should be sized for peak discharge current
  • Generator leads must handle full rated output continuously
  • DC wiring requires larger gauge than AC for the same power
What wire gauge do I need for a 30A solar charge controller?

For 30A at short distances (under 10ft), use 10 AWG. For longer runs, upgrade to 8 AWG or 6 AWG to minimize voltage drop.

What size wire for a 48V battery bank at 100A?

100A requires at least 2 AWG copper wire (rated 95A, so use 1/0 AWG for safety margin). For runs over 5 feet, use 1/0 AWG or larger.

How do I account for voltage drop in long wire runs?

For every 10 feet beyond the first 10, increase the wire size by one gauge. Alternatively, use a voltage drop calculator with specific resistance values: Voltage Drop = 2 x Length x Current x Resistance per foot.