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🔌 Circuit Calculator

🔌 Circuit Calculator

Calculate circuit load, breaker size, and wire sizing. Perfect for DIY projects and planning.

⚡ Enter Circuit Parameters:
Volts
Watts
PF
Resistive: 1.0 | Motors: 0.8 | Electronics: 0.95
For voltage drop calculation (round-trip distance)
Quick Examples:
⚡ Electrical Safety & Standards
Formulas:
• Single-phase: I = P ÷ (V × PF)
• Three-phase: I = P ÷ (√3 × V × PF)
• Voltage drop: Vdrop = 2 × L × I × R
⚠️ Safety First!
• Always consult licensed electricians
• Follow NEC/IEC/BS 7671 codes
• Use proper circuit protection
Breaker Sizing
• Continuous loads: 125% rule
• Non-continuous: 100% rule
• Match wire ampacity
Pro Tips
• Calculate round-trip distance
• Factor in ambient temperature
• Consider future expansion
• Include derating factors
📋 Common Wire Sizes & Ampacities:
AWG mm² Max Ampacity* Typical Use
142.0815ALighting circuits
123.3120AGeneral outlets
105.2630ADryers, water heaters
88.3740ARanges, HVAC
613.355AElectric vehicle
* For 75°C copper wire in free air. Actual values vary by installation.
Disclaimer:
This tool provides educational estimates only. Always consult with a qualified electrician and follow local electrical codes for actual installations.

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