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Electrical Power Formula:
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Electrical power consumption refers to the amount of electrical energy used by an appliance or device over time. It is calculated using the formula P = V × I × PF, where P is power in watts, V is voltage in volts, I is current in amperes, and PF is the power factor.
The calculator uses the electrical power formula:
Where:
Explanation: This formula calculates the real power consumed by an electrical device, taking into account the phase relationship between voltage and current through the power factor.
Details: Accurate power calculation is essential for electrical system design, energy consumption monitoring, circuit protection sizing, and cost estimation for electricity usage.
Tips: Enter voltage in volts, current in amperes, and power factor (typically 0.8-1.0 for most appliances). For resistive loads like incandescent bulbs, use power factor of 1.0.
Q1: What is power factor and why is it important?
A: Power factor represents the efficiency of power usage. A lower power factor means more current is required to deliver the same amount of real power, leading to higher energy losses.
Q2: How do I find the voltage and current values?
A: Voltage is typically listed on the appliance (e.g., 120V, 240V). Current can be measured with a multimeter or found on the device's specification label.
Q3: What's the difference between real power and apparent power?
A: Real power (P) is the actual power consumed, measured in watts. Apparent power (S = V × I) is the product of voltage and current, measured in volt-amperes (VA).
Q4: When should I use power factor less than 1?
A: Use PF < 1 for inductive loads like motors, transformers, and fluorescent lights. For purely resistive loads (heaters, incandescent bulbs), use PF = 1.
Q5: How can I calculate energy consumption from power?
A: Energy (kWh) = Power (kW) × Time (hours). Multiply the calculated power by the usage time to get total energy consumption.