1. What is the Watts to Amps Calculation?

The Watts to Amps calculation determines the electrical current drawn by a PC power supply based on its wattage rating, accounting for voltage and power factor. This helps ensure proper circuit sizing and prevents overloading.

2. How Does the Calculator Work?

The calculator uses the power formula:

Where:

• \( I \) — Current in amperes (A)
• \( P_{total} \) — Total power in watts (W)
• \( V \) — Voltage in volts (V)
• \( PF \) — Power factor (unitless, 0 to 1)

Explanation: The formula converts power (watts) to current (amps) by accounting for voltage and the efficiency of power conversion (power factor).

3. Importance of Power Factor

Details: Power factor represents how effectively electrical power is converted to useful work. PC power supplies typically have power factors between 0.9-1.0. Lower power factors mean more current is required for the same wattage.

4. Using the Calculator

Tips:

• Enter the total wattage from your power supply label
• Use your local voltage (120V in North America, 230V in Europe)
• For modern PC power supplies, use 0.95 as default power factor

5. Frequently Asked Questions (FAQ)

Q1: Why is my actual current draw different?
A: Actual draw varies with system load. This calculation shows maximum potential draw at full load.

Q2: What power factor should I use?
A: For modern 80+ certified PSUs: 0.95-0.99. For older PSUs: 0.7-0.8.

Q3: How does this relate to circuit breakers?
A: Ensure your circuit can handle the calculated amps. Standard 15A circuits can handle ~1800W at 120V.

Q4: Should I use peak or continuous wattage?
A: Use the continuous (rated) wattage for safety calculations.

Q5: Does this work for three-phase systems?
A: No, this is for single-phase AC systems. Three-phase requires a different calculation.