Motor Efficiency Calculator

How Motor Efficiency works

For Motor Efficiency, use efficiency = output ÷ input × 100. Motor Efficiency uses Shaft output power, Electrical input power to report Motor efficiency.

With the loaded values, motor efficiency evaluates to 88.00%. Test shaft output power separately and preserve the baseline motor efficiency.

Inputs for Motor Efficiency

Shaft output power and Electrical input power belong to Motor Efficiency. Keep source units with shaft output power.

The Motor Efficiency defaults demonstrate arithmetic only. Replace shaft output power with case-specific data.

Shaft output power

Example entry: 11 kW.

Electrical input power

Example entry: 12.5 kW.

Reading the Motor Efficiency result

This output represents Motor Efficiency.

Before selecting equipment for Motor Efficiency, compare motor efficiency with available ratings and operating limits.

Measurement and units

Motor nameplate data, duty, enclosure, starting method, load profile, and thermal limits govern final selection. Check prefixes on shaft output power.

Keep the shaft output power unit and measurement point consistent across Motor Efficiency cases.

Limits of this calculation

Compare values at the same operating point.

Only the listed Motor Efficiency inputs contribute to motor efficiency. Unentered effects remain outside Motor Efficiency.

A useful Motor Efficiency comparison

Record motor efficiency before testing a different shaft output power value.

Document the alternate shaft output power source.

Motor Efficiency record notes

Record source and operating details for shaft output power. Compare this result with Motor Poles Frequency Calculator when required pole count is also needed.

Retain raw motor efficiency beside its selected rating.

Questions about Motor Efficiency