Energy & Electronics/

Voltage Drop Calculator

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Voltage Drop Calculation

Calculate voltage drop in electrical circuits to ensure proper wire sizing. Voltage drop occurs when internal resistance of the wire causes a decrease in voltage at the load end. Excessive voltage drop can damaging equipment or cause it to run inefficiently.

Recommendations

  • Lighting/Sensitive Equipment: Aim for less than 3% voltage drop.
  • General Motors/Appliances: Aim for less than 5% voltage drop.
  • Wire Material: Copper is the standard. Aluminum has higher resistance, requiring larger gauges for the same current.