1. What is the Electric Current Formula?

The electric current formula (I = P/V) calculates the current flowing in an electrical circuit based on power and voltage. It's fundamental for designing and analyzing electrical systems, particularly for electric motors.

2. How Does the Calculator Work?

The calculator uses the basic electrical formula:

Where:

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

Explanation: The formula shows the direct relationship between power and current, and the inverse relationship between voltage and current.

3. Importance of Current Calculation

Details: Accurate current calculation is crucial for selecting proper wire sizes, circuit breakers, and motor protection devices to ensure safe and efficient operation of electrical systems.

4. Using the Calculator

Tips: Enter power in watts and voltage in volts. Both values must be positive numbers. For three-phase systems, additional factors need to be considered.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between single-phase and three-phase current calculation?
A: Three-phase calculations require multiplying by √3 (1.732) and considering power factor: \( I = P / (V \times \sqrt{3} \times PF) \).

Q2: How does power factor affect current calculation?
A: For AC systems, actual current is higher than calculated when power factor is less than 1. Always consider power factor in real-world applications.

Q3: What are typical current ratings for household appliances?
A: Small appliances: 1-10A; Large appliances: 15-30A; Central AC: 20-50A. Always check nameplate ratings.

Q4: Why is current calculation important for motor selection?
A: Proper current calculation ensures the motor won't overload the circuit and helps select appropriate overload protection devices.

Q5: How does efficiency affect current draw?
A: Less efficient motors draw more current for the same power output. Input power (used in calculation) is output power divided by efficiency.