1. What is Power Supply Calculation?

Power supply calculation determines the amount of electrical power (in watts) being consumed or required by a device or circuit. It's fundamental in electrical engineering and electronics design.

2. How Does the Calculator Work?

The calculator uses the basic power equation:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Voltage in volts (V)
• \( I \) — Current in amperes (A)

Explanation: This fundamental equation shows that power is the product of voltage and current in a DC circuit or purely resistive AC circuit.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for designing power supplies, selecting appropriate components, ensuring circuit safety, and optimizing energy efficiency.

4. Using the Calculator

Tips: Enter voltage in volts and current in amps. Both values must be positive numbers. The calculator will compute the power in watts.

5. Frequently Asked Questions (FAQ)

Q1: Is this formula valid for AC circuits?
A: This simple formula works for DC circuits and AC circuits with purely resistive loads. For reactive loads, power factor must be considered.

Q2: What's 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 RMS voltage and current. They differ in AC circuits with reactive components.

Q3: How does this relate to energy consumption?
A: Energy is power multiplied by time. For example, 100 watts for 10 hours = 1,000 watt-hours (1 kWh).

Q4: Why is power calculation important for power supplies?
A: Proper power supply sizing prevents overheating, ensures reliable operation, and maintains efficiency. Undersized supplies may fail or cause voltage drops.

Q5: How do I account for efficiency in power supply design?
A: Divide the calculated power by the supply's efficiency rating (typically 0.7-0.95) to determine input power requirements.