Phase Current Calculator

Phase Current Formula:

\[ I_{phase} = \frac{V_{phase}}{Z_{phase}} \]

Phase Current (I_phase):

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1. What is Phase Current?

Phase current (I_phase) is the current flowing through each phase in an AC electrical circuit. It is calculated using Ohm's law for AC circuits, where current equals voltage divided by impedance.

2. How Does the Calculator Work?

The calculator uses the phase current formula:

\[ I_{phase} = \frac{V_{phase}}{Z_{phase}} \]

Where:

\( I_{phase} \) — Phase current in amperes (A)
\( V_{phase} \) — Phase voltage in volts (V)
\( Z_{phase} \) — Phase impedance in ohms (Ω)

Explanation: This formula applies Ohm's law to AC circuits, where impedance (Z) represents the total opposition to current flow, combining resistance and reactance.

3. Importance of Phase Current Calculation

Details: Accurate phase current calculation is essential for proper circuit design, component sizing, protection device selection, and ensuring electrical system safety and efficiency.

4. Using the Calculator

Tips: Enter phase voltage in volts and phase impedance in ohms. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between phase current and line current?
A: Phase current flows through each phase winding, while line current flows in the transmission lines. In star connection, they are equal; in delta connection, line current is √3 times phase current.

Q2: How does impedance differ from resistance?
A: Resistance opposes DC current, while impedance opposes AC current and includes both resistance and reactance (inductive and capacitive).

Q3: When is this formula applicable?
A: This formula applies to balanced three-phase systems and single-phase AC circuits where voltage and impedance are known.

Q4: What are typical phase current values?
A: Phase current values vary widely depending on the application, from milliamps in electronic circuits to hundreds of amps in power systems.

Q5: How does power factor affect phase current?
A: Lower power factor increases phase current for the same real power, requiring larger conductors and equipment. The formula accounts for power factor through impedance.