What is the standard measurement for evaluating motor efficiency?

The standard measurement for evaluating motor efficiency is expressed as a percentage. Motor efficiency refers to how well a motor converts electrical energy into mechanical energy, and this conversion is often evaluated by comparing the output power with the input power. The formula used to calculate efficiency is:

Efficiency (%) = (Output Power / Input Power) × 100

This percentage indicates the proportion of input energy that is successfully transformed into useful work, with the remaining energy typically lost as heat or through other forms of energy dissipation. A higher percentage reflects a more efficient motor, meaning that it uses electricity more effectively.

The other options do not measure motor efficiency. Wattage reflects electrical power but does not directly assess how effectively that power is used. Decibels measure sound intensity and are irrelevant to motor efficiency. Amperes indicate electrical current but do not provide information about energy conversion efficiency. Thus, percentage is the accurate and standard measurement used to quantify and compare motor efficiency.