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Single-Phase Power Formula:
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The motor power calculation determines the electrical power consumed by a single-phase AC motor based on voltage, current, and power factor. This helps in sizing electrical components and estimating energy consumption.
The calculator uses the single-phase power formula:
Where:
Explanation: The formula calculates real power (actual work done) as opposed to apparent power (V×I). The power factor accounts for phase difference between voltage and current.
Details: Accurate power calculation is essential for proper circuit design, selecting appropriate wire sizes, circuit breakers, and energy management. It helps prevent electrical overloads and ensures efficient operation.
Tips: Enter voltage in volts, current in amps, and power factor (typically 0.8 for motors unless known otherwise). All values must be positive numbers (voltage > 0, current > 0, 0 < PF ≤ 1).
Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing how effectively current is being converted into useful work. For motors, it's typically between 0.7 and 0.9.
Q2: How does this differ for three-phase motors?
A: Three-phase power calculation includes a √3 factor: P = √3 × V × I × PF. Use a three-phase calculator for those motors.
Q3: Why is my motor drawing more current than calculated?
A: Motors draw more current under load. The nameplate current rating is typically the full-load current. Starting current can be 4-8 times higher.
Q4: How can I improve power factor?
A: Power factor correction capacitors can be added to reduce reactive power and improve power factor, especially in industrial settings.
Q5: Is this the same as mechanical power output?
A: No, this calculates electrical input power. Mechanical output power would be less due to motor efficiency (typically 70-95% for electric motors).