Voltage Drop Calculator

Calculate voltage drop in electrical circuits based on wire size, length, current, and material. This helps ensure proper voltage levels for your electrical system.

Enter the current flowing through the circuit
Select the source voltage
Select the wire gauge
Enter the one-way length of the wire
Select the wire material
Select the circuit phase

Maximum Voltage Drop Guidelines

Application Maximum Voltage Drop Notes
Branch Circuits 3% General purpose circuits
Feeder Circuits 2% Main power distribution
Combined Drop 5% Total from source to load
Critical Loads 1-2% Medical equipment, sensitive electronics
DC Systems 2% Solar, battery systems

Factors Affecting Voltage Drop

  • Wire length and size
  • Current flow
  • Wire material resistivity
  • Circuit phase configuration
  • Temperature effects
  • Connection resistance
  • Load type and characteristics

Tips to Minimize Voltage Drop

  • Use larger wire sizes for long runs
  • Keep wire runs as short as possible
  • Use copper instead of aluminum when possible
  • Maintain proper connections
  • Consider temperature derating
  • Use appropriate wire insulation
  • Regularly inspect connections