420 kW to Amps at 480V Three-Phase AC (US Industrial)
Exact current (Amps), real power (kW), apparent power (kVA), mechanical horsepower (HP), breaker rating, and conductor size for 420 kW on a 480V Three-Phase AC (US Industrial) circuit.
Line Current (0.85 PF)594.33 AAt 1.0 PF: 505.18 A
Active / Apparent Power420.0 kW494.12 kVA · 260.29 kVAR
Recommended Breaker800 A (NEC)600 A (IEC Nominal)
Recommended Copper Wire2× 1000 kcmil (Parallel)IEC Metric: 2× 400 mm²
Engineering Breakdown for 420 kW at 480V
| Input Rating | 420 kW (480V Three-Phase AC (US Industrial)) |
| Amperage at 0.85 Power Factor (Industrial Motor/Transformer) | 594.33 Amps |
| Amperage at 1.00 Power Factor (Resistive Load) | 505.18 Amps |
| Real Power (kW / Watts) | 420.0 kW (420,000 W) |
| Apparent Power (kVA) & Reactive Power (kVAR) | 494.12 kVA / 260.29 kVAR |
| Equivalent Mechanical Horsepower (HP) | 563.23 HP |
| NEC 125% Continuous Circuit Breaker | 800 A |
| Minimum Copper Conductor (100 ft / 30 m, ≤3% Drop) | 2× 1000 kcmil (Parallel) (NEC) / 2× 400 mm² (IEC) |
Frequently Asked Questions
How many amps is 420 kW at 480V (3-Phase)?
At 480V Three-Phase AC (US Industrial), 420 kW equals 594.33 Amps at an industrial power factor of 0.85 (or 505.18 Amps at unity power factor 1.0).
What size breaker and wire is needed for 420 kW at 480V?
For 594.33A continuous load, NEC requires a 125% rated breaker of 800A with 2× 1000 kcmil (Parallel) copper conductors, while IEC standard sizing uses a 600A breaker with 2× 400 mm² copper cable.
Other Power Ratings & Voltages
5 kW at 480V (3P)10 kW at 480V (3P)15 kW at 480V (3P)20 kW at 480V (3P)25 kW at 480V (3P)30 kW at 480V (3P)45 kW at 480V (3P)50 kW at 480V (3P)75 kW at 480V (3P)100 kW at 480V (3P)150 kW at 480V (3P)200 kW at 480V (3P)250 kW at 480V (3P)500 kW at 480V (3P)420 kW at 120V Single-Phase AC420 kW at 208V Single-Phase AC420 kW at 230V Single-Phase AC (IEC)420 kW at 240V Single-Phase AC (NEC)420 kW at 208V Three-Phase AC420 kW at 230V Three-Phase AC420 kW at 400V Three-Phase AC (IEC Europe)420 kW at 415V Three-Phase AC (UK / AU)420 kW at 600V Three-Phase AC (Canada / Heavy)420 kW at 24V DC Direct Current420 kW at 48V DC Battery / Telecom Bus