Solar Wire Size Calculator

Calculate the appropriate wire size for your solar power system based on current, voltage drop, and distance requirements.

Maximum current that will flow through the wire
Nominal system voltage
Length of wire run from source to load
Choose between copper or aluminum conductors
Recommended: 2% for DC circuits, max 3% for critical loads
Average temperature where wire will be installed

How to Use This Calculator

  1. Maximum Current: Enter the highest current that will flow through the wire.
  2. System Voltage: Select your nominal system voltage.
  3. Distance: Input the one-way length of the wire run.
  4. Wire Material: Choose between copper and aluminum conductors.
  5. Voltage Drop: Specify maximum acceptable voltage drop percentage.
  6. Temperature: Enter the ambient temperature where wire will be installed.

Wire Size Reference Table

AWG Size Copper Max Amps (75°C) Aluminum Max Amps (75°C)
142015
122520
103530
85040
66550
48565
211590
1130100
1/0150120
2/0175135

Important Considerations:

  • Always follow local electrical codes and regulations
  • Use appropriate wire insulation for the installation environment
  • Consider derating factors for high temperatures
  • Use proper termination methods and connectors
  • Include appropriate safety factors for future expansion
  • Consider voltage drop for long wire runs

For critical installations, consult with a qualified electrician to verify calculations.