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Motor Efficiency Formula:
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Motor efficiency is a measure of how effectively a motor converts electrical input power into mechanical output power. It is expressed as a percentage and indicates the proportion of input energy that is usefully converted to work.
The calculator uses the motor efficiency formula:
Where:
Explanation: The formula calculates the ratio of useful output power to total input power, multiplied by 100 to express as a percentage.
Details: Calculating motor efficiency is crucial for energy conservation, cost savings, and environmental sustainability. Higher efficiency motors reduce energy consumption and operating costs while lowering carbon emissions.
Tips: Enter both output power and input power in watts. Ensure input power is greater than or equal to output power for valid results. All values must be positive numbers.
Q1: What is a good motor efficiency percentage?
A: Modern electric motors typically have efficiencies between 70-95%, with higher efficiency motors achieving 90% or more. Premium efficiency motors can reach 95-97%.
Q2: Why can't efficiency be 100%?
A: Due to energy losses from friction, heat, magnetic losses, and electrical resistance, no motor can achieve 100% efficiency as some energy is always wasted.
Q3: How does motor size affect efficiency?
A: Generally, larger motors tend to be more efficient than smaller ones due to better scaling of electromagnetic properties and reduced relative losses.
Q4: What factors affect motor efficiency?
A: Key factors include motor design, materials used, operating temperature, load conditions, maintenance quality, and power quality.
Q5: How often should motor efficiency be measured?
A: Efficiency should be checked during initial commissioning, after major repairs, and periodically during maintenance to ensure optimal performance.