Current Calculation Formula for 1 Phase

Single-Phase Current Formula:

\[ I = \frac{P_{kW} \times 1000}{V \times PF} \]

Current (I): amps

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1. What is Single-Phase Current Calculation?

Definition: This calculator determines the electrical current in amperes (A) for single-phase AC circuits based on power, voltage, and power factor.

Purpose: It helps electricians, engineers, and DIYers properly size wires, circuit breakers, and other electrical components.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ I = \frac{P_{kW} \times 1000}{V \times PF} \]

Where:

\( I \) — Current (amperes)
\( P_{kW} \) — Power (kilowatts)
\( V \) — Voltage (volts)
\( PF \) — Power factor (unitless, between 0 and 1)

Explanation: The power in kW is converted to watts (×1000), then divided by the product of voltage and power factor.

3. Importance of Current Calculation

Details: Accurate current calculation ensures electrical safety, prevents circuit overloads, and helps select properly sized components.

4. Using the Calculator

Tips: Enter the power in kW, circuit voltage (default 120V), and power factor (default 0.8). All values must be > 0, and PF between 0.01 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor represents the ratio of real power to apparent power, typically between 0 and 1. It accounts for phase difference between voltage and current.

Q2: What's a typical power factor value?
A: For residential circuits, 0.8-0.9 is common. Motors may have lower PF (0.6-0.8). Pure resistive loads have PF=1.

Q3: Why multiply power by 1000?
A: The formula converts kilowatts (kW) to watts (W) since 1 kW = 1000 W.

Q4: Can I use this for DC circuits?
A: For DC, set PF=1 since there's no phase difference in DC circuits.

Q5: How does voltage affect current?
A: Higher voltage results in lower current for the same power, following Ohm's Law (P=VI).