4 kW to Amps at 240V Single-Phase AC (NEC)
Exact current (Amps), real power (kW), apparent power (kVA), mechanical horsepower (HP), breaker rating, and conductor size for 4 kW on a 240V Single-Phase AC (NEC) circuit.
Line Current (0.85 PF)19.61 AAt 1.0 PF: 16.67 A
Active / Apparent Power4.0 kW4.71 kVA · 2.48 kVAR
Recommended Breaker25 A (NEC)20 A (IEC Nominal)
Recommended Copper Wire10 AWGIEC Metric: 4 mm²
Engineering Breakdown for 4 kW at 240V
| Input Rating | 4 kW (240V Single-Phase AC (NEC)) |
| Amperage at 0.85 Power Factor (Industrial Motor/Transformer) | 19.61 Amps |
| Amperage at 1.00 Power Factor (Resistive Load) | 16.67 Amps |
| Real Power (kW / Watts) | 4.0 kW (4,000 W) |
| Apparent Power (kVA) & Reactive Power (kVAR) | 4.71 kVA / 2.48 kVAR |
| Equivalent Mechanical Horsepower (HP) | 5.36 HP |
| NEC 125% Continuous Circuit Breaker | 25 A |
| Minimum Copper Conductor (100 ft / 30 m, ≤3% Drop) | 10 AWG (NEC) / 4 mm² (IEC) |
Frequently Asked Questions
How many amps is 4 kW at 240V (1-Phase)?
At 240V Single-Phase AC (NEC), 4 kW equals 19.61 Amps at an industrial power factor of 0.85 (or 16.67 Amps at unity power factor 1.0).
What size breaker and wire is needed for 4 kW at 240V?
For 19.61A continuous load, NEC requires a 125% rated breaker of 25A with 10 AWG copper conductors, while IEC standard sizing uses a 20A breaker with 4 mm² copper cable.
Other Power Ratings & Voltages
5 kW at 240V (1P)10 kW at 240V (1P)15 kW at 240V (1P)20 kW at 240V (1P)25 kW at 240V (1P)30 kW at 240V (1P)45 kW at 240V (1P)50 kW at 240V (1P)75 kW at 240V (1P)100 kW at 240V (1P)150 kW at 240V (1P)200 kW at 240V (1P)250 kW at 240V (1P)500 kW at 240V (1P)4 kW at 120V Single-Phase AC4 kW at 208V Single-Phase AC4 kW at 230V Single-Phase AC (IEC)4 kW at 208V Three-Phase AC4 kW at 230V Three-Phase AC4 kW at 400V Three-Phase AC (IEC Europe)4 kW at 415V Three-Phase AC (UK / AU)4 kW at 480V Three-Phase AC (US Industrial)4 kW at 600V Three-Phase AC (Canada / Heavy)4 kW at 24V DC Direct Current4 kW at 48V DC Battery / Telecom Bus