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🏭 Industrial Electrical Conversion · Three-Phase & Single-Phase

42 kW to Amps at 415V Three-Phase AC (UK / AU)

Exact current (Amps), real power (kW), apparent power (kVA), mechanical horsepower (HP), breaker rating, and conductor size for 42 kW on a 415V Three-Phase AC (UK / AU) circuit.

Line Current (0.85 PF)68.74 AAt 1.0 PF: 58.43 A
Active / Apparent Power42.0 kW49.41 kVA · 26.03 kVAR
Recommended Breaker90 A (NEC)70 A (IEC Nominal)
Recommended Copper Wire4 AWGIEC Metric: 16 mm²

Engineering Breakdown for 42 kW at 415V

Input Rating42 kW (415V Three-Phase AC (UK / AU))
Amperage at 0.85 Power Factor (Industrial Motor/Transformer)68.74 Amps
Amperage at 1.00 Power Factor (Resistive Load)58.43 Amps
Real Power (kW / Watts)42.0 kW (42,000 W)
Apparent Power (kVA) & Reactive Power (kVAR)49.41 kVA / 26.03 kVAR
Equivalent Mechanical Horsepower (HP)56.32 HP
NEC 125% Continuous Circuit Breaker90 A
Minimum Copper Conductor (100 ft / 30 m, ≤3% Drop)4 AWG (NEC) / 16 mm² (IEC)

Frequently Asked Questions

How many amps is 42 kW at 415V (3-Phase)?

At 415V Three-Phase AC (UK / AU), 42 kW equals 68.74 Amps at an industrial power factor of 0.85 (or 58.43 Amps at unity power factor 1.0).

What size breaker and wire is needed for 42 kW at 415V?

For 68.74A continuous load, NEC requires a 125% rated breaker of 90A with 4 AWG copper conductors, while IEC standard sizing uses a 70A breaker with 16 mm² copper cable.

Other Power Ratings & Voltages

5 kW at 415V (3P)10 kW at 415V (3P)15 kW at 415V (3P)20 kW at 415V (3P)25 kW at 415V (3P)30 kW at 415V (3P)45 kW at 415V (3P)50 kW at 415V (3P)75 kW at 415V (3P)100 kW at 415V (3P)150 kW at 415V (3P)200 kW at 415V (3P)250 kW at 415V (3P)500 kW at 415V (3P)42 kW at 120V Single-Phase AC42 kW at 208V Single-Phase AC42 kW at 230V Single-Phase AC (IEC)42 kW at 240V Single-Phase AC (NEC)42 kW at 208V Three-Phase AC42 kW at 230V Three-Phase AC42 kW at 400V Three-Phase AC (IEC Europe)42 kW at 480V Three-Phase AC (US Industrial)42 kW at 600V Three-Phase AC (Canada / Heavy)42 kW at 24V DC Direct Current42 kW at 48V DC Battery / Telecom Bus