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3 Phase Breaker Calculation:
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The 3 Phase Breaker Calculation determines the current (in amperes) required for a three-phase electrical system based on power (in watts) and voltage (in volts). This is essential for selecting the appropriate circuit breaker size to ensure safety and system reliability.
The calculator uses the 3 Phase formula:
Where:
Explanation: This formula calculates the current flow in a balanced three-phase system, accounting for the phase relationship between the voltages.
Details: Correct breaker sizing prevents electrical hazards such as overloads, short circuits, and potential fires. It ensures the electrical system operates within safe limits and complies with electrical codes.
Tips: Enter the power in watts and voltage in volts. Both values must be positive numbers. The result will be the current in amperes, which can guide breaker selection.
Q1: Why is the square root of 3 used in the formula?
A: The square root of 3 accounts for the phase difference in a three-phase system, where the voltage between phases is √3 times the phase-to-neutral voltage.
Q2: What is a typical voltage for three-phase systems?
A: Common voltages include 208V, 240V, 480V, and 600V, depending on the region and application.
Q3: How do I choose a breaker based on the calculated amps?
A: Select a breaker with a rating equal to or next highest standard value above the calculated current, considering any safety margins required by local codes.
Q4: Can this calculator be used for single-phase systems?
A: No, this calculator is specifically for three-phase systems. For single-phase, use Amps = P / V.
Q5: Where can I find breakers at Home Depot?
A: Home Depot carries a wide range of circuit breakers in the electrical department, available for various brands and amperage ratings.