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Power Formula:
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Power calculation using voltage and current is a fundamental electrical engineering principle that determines the electrical power consumed or produced in a circuit. The relationship is defined by the formula P = V × I, where P is power in watts, V is voltage in volts, and I is current in amperes.
The calculator uses the power formula:
Where:
Explanation: This formula applies to DC circuits and single-phase AC circuits with power factor of 1. The power represents the rate at which electrical energy is transferred or converted.
Details: Accurate power calculation is essential for circuit design, electrical system sizing, energy consumption analysis, safety compliance, and determining appropriate component ratings in electrical installations.
Tips: Enter voltage in volts and current in amperes. Both values must be positive numbers greater than zero. The calculator will compute the power in watts.
Q1: Does this formula work for AC circuits?
A: This formula works for DC circuits and single-phase AC circuits with unity power factor. For AC circuits with power factor less than 1, use P = V × I × PF.
Q2: What is the difference between real power and apparent power?
A: Real power (watts) is the actual power consumed, while apparent power (VA) is the product of voltage and current. In DC circuits, they are equal.
Q3: How do I calculate power for three-phase systems?
A: For three-phase systems, use P = √3 × V × I × PF for balanced loads, where V is line voltage and I is line current.
Q4: What are typical voltage and current ranges?
A: Common voltages include 12V, 24V, 120V, 230V, etc. Current ranges vary from milliamps to hundreds of amps depending on the application.
Q5: Why is power calculation important for electrical safety?
A: Proper power calculation ensures components are not overloaded, preventing overheating, fire hazards, and equipment damage in electrical systems.