calc.engineer / Solar & Power / Wire Gauge
Wire Gauge v1.0.0
Determines the minimum AWG (American Wire Gauge) conductor size for a given current, voltage, one-way cable distance, and maximum allowable voltage drop percentage. Supports copper and aluminum conductors. Computes round-trip resistance, actual voltage drop in volts and percent, and wire cross-sectional area. Essential for DC solar runs, battery bank wiring, EV charging circuits, and low-voltage landscape lighting. NEC recommends 3% max drop for branch circuits and 5% total including feeder. Outputs the smallest AWG that satisfies the drop constraint.
Fill in the inputs and Compute to see the structured result.
From an agent (MCP) or the API
curl -X POST https://calc.engineer/api/wire_gauge \
-H "Content-Type: application/json" \
-d '{"current_amps": …, "voltage": …, "distance_m": …}'MCP: connect to https://calc.engineer/mcp and call wire_gauge.
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