1. What is Full Load Amps (FLA)?

Full Load Amps (FLA) is the current a motor draws while operating at its rated load and voltage. It's a crucial parameter for sizing motor protection devices, conductors, and starters.

2. How Does the Calculator Work?

The calculator uses the 3-phase motor current formula:

Where:

• \( I \) — Full load current (amps)
• \( P \) — Motor power (watts)
• \( V \) — Line voltage (volts)
• \( PF \) — Power factor (0-1)
• \( \eta \) — Motor efficiency (0-1)

Explanation: The formula accounts for real power consumption (P), system voltage, and losses due to power factor and motor efficiency.

3. Importance of FLA Calculation

Details: Accurate FLA calculation is essential for proper motor circuit design, preventing overheating, and ensuring reliable operation. It helps in selecting the right circuit breakers, overload protection, and wire sizes.

4. Using the Calculator

Tips: Enter motor power in watts, line voltage in volts, power factor (typically 0.8-0.95), and motor efficiency (typically 0.8-0.95 for most industrial motors). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between FLA and LRA?
A: FLA is the current at full load, while LRA (Locked Rotor Amps) is the current when the motor is stalled (typically 5-7 times FLA).

Q2: How do I find my motor's power factor?
A: Check motor nameplate or manufacturer specs. Typical values are 0.85 for standard motors, 0.95 for high-efficiency models.

Q3: What if I have horsepower instead of watts?
A: Convert HP to watts (1 HP = 746 watts) before using the calculator.

Q4: Does this work for single-phase motors?
A: No, single-phase motors use a different formula (I = P / (V × PF × η)).

Q5: Why is efficiency important?
A: Efficiency accounts for power losses in the motor. Higher efficiency means less current for the same output power.