Estimate single-phase and three-phase motor current using horsepower or kilowatts, voltage, efficiency, and power factor.
Use this for early electrical design, feeder estimates, wire sizing checks, overload review, control panel planning, and automation retrofit work.
Motor current is usually an early sizing check. After estimating current, verify voltage drop, wire size, ampacity reference values, and any PLC or panel-side design concerns.
Start with motor current, then check wiring and electrical delivery.
Estimate motor amps using horsepower or kilowatts, voltage, phase, efficiency, and power factor.
This calculator provides an engineering estimate. Actual motor nameplate current can vary by motor design, service factor, efficiency class, starting method, and manufacturer. Always verify final values using motor nameplate data and applicable electrical code requirements.
Common industrial motor estimate for small-to-medium automation equipment.
Useful for smaller single-phase equipment or utility motor estimates.
Use this when your motor power is listed in kilowatts instead of horsepower.
Save motor current setups, reload previous inputs, and reuse common electrical sizing checks.
This calculator is intended for practical estimating. For final design, always verify actual motor nameplate current, overload settings, conductor sizing, branch circuit protection, applicable electrical code requirements, and site-specific standards.
Calculated FLA is useful for planning, but real motors may not match perfectly. Nameplate current and applicable electrical standards should drive final design decisions.
Approximate full load current values for common 3-phase motors at typical industrial voltages.
| Motor Size | 230V 3-Phase | 460V 3-Phase | 575V 3-Phase |
|---|---|---|---|
| 1 HP | 3.2 A | 1.6 A | 1.3 A |
| 2 HP | 6.0 A | 3.0 A | 2.4 A |
| 3 HP | 9.6 A | 4.8 A | 3.9 A |
| 5 HP | 15.2 A | 7.6 A | 6.1 A |
| 7.5 HP | 22.0 A | 11.0 A | 8.8 A |
| 10 HP | 28.0 A | 14.0 A | 11.2 A |
| 15 HP | 42.0 A | 21.0 A | 16.8 A |
| 20 HP | 54.0 A | 27.0 A | 21.6 A |
| 25 HP | 68.0 A | 34.0 A | 27.2 A |
| 30 HP | 80.0 A | 40.0 A | 32.0 A |
Reference table values are approximate and intended for quick comparison only. For final design, always confirm motor nameplate current and applicable code tables.
Once you know the estimated motor current, the next step is checking voltage drop, conductor sizing, ampacity references, and panel-side electrical design details.
Use this after estimating current to check whether the circuit will deliver enough voltage under load.
Use this when moving from estimated current into conductor sizing and practical electrical design checks.
Use this to jump back into the larger troubleshooting and electrical workflow system.
If you are sizing feeders, selecting controls hardware, planning a retrofit, checking motor loads, or reviewing a machine electrical issue, use the support path below.
These pages work best together when you are validating motors, wiring, field power, and controls-panel sizing.