Motor Full Load Current Calculator
Calculate full load current for single-phase and three-phase AC motors. Determine wire sizing, breaker requirements, and motor protection based on electrical specifications.
Step 1: Motor Specifications
Understanding Full Load Current
Full Load Current (FLC) is the current drawn by a motor when operating at its rated power, voltage, and frequency. This is critical for selecting proper wire size, circuit breakers, and overload protection devices.
Step 2: Calculation Options
Full Load Current Formulas
Single-Phase: I = P / (V × PF × Eff)
Three-Phase: I = P / (√3 × V × PF × Eff)
DC Motor: I = P / (V × Eff)
Where P is power in watts, V is voltage, PF is power factor, Eff is efficiency.
Motor Full Load Current Results
Full Load Current
Protection & Sizing Recommendations
| Component | Recommended Size | Standard | Notes |
|---|
Important Safety Notes
Always consult local electrical codes (NEC, IEC, etc.) and a qualified electrician before installation. These recommendations are for informational purposes only and assume normal operating conditions.
Motor Current Calculation Formulas
Single-Phase AC Motors
Formula: I = P / (V × PF × η)
Where: I = Current (Amps), P = Power (Watts), V = Voltage (Volts), PF = Power Factor, η = Efficiency
Example: 5 HP (3730W), 230V, PF=0.8, Efficiency=0.85 → I = 3730 / (230 × 0.8 × 0.85) = 26.1 A
Three-Phase AC Motors
Formula: I = P / (√3 × V × PF × η)
Where: √3 ≈ 1.732 (three-phase constant)
Example: 10 HP (7460W), 400V, PF=0.85, Efficiency=0.9 → I = 7460 / (1.732 × 400 × 0.85 × 0.9) = 14.1 A
DC Motors
Formula: I = P / (V × η)
Example: 2 HP (1492W), 120V, Efficiency=0.88 → I = 1492 / (120 × 0.88) = 14.1 A
Power Unit Conversions
Horsepower to Watts: 1 HP = 746 W
Kilowatts to Watts: 1 kW = 1000 W
Watts to HP: 1 W = 0.00134 HP
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