1. What is Full Load Current?

Full Load Current (FLC) is the maximum current drawn by an electric motor when operating at its rated power (in this case 90kW) under full mechanical load.

2. How Does the Calculator Work?

The calculator uses the Full Load Current equation:

Where:

• 90 × 1000 — Converts kW to Watts (90,000W)
• √3 — Factor for three-phase systems (≈1.732)
• Voltage — Line voltage in volts
• Power Factor — Ratio of real power to apparent power (typically 0.8-0.95)
• Efficiency — Motor efficiency (typically 0.85-0.95)

Explanation: The equation accounts for the electrical characteristics of three-phase motors and their power conversion efficiency.

3. Importance of FLC Calculation

Details: Knowing the full load current is essential for proper circuit breaker sizing, cable selection, overload protection settings, and overall electrical system design.

4. Using the Calculator

Tips: Enter voltage in volts, power factor as decimal (e.g., 0.85), and efficiency as decimal (e.g., 0.9). All values must be positive (voltage > 0, 0 < power factor ≤ 1, 0 < efficiency ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: Why is power factor important in FLC calculation?
A: Power factor represents how effectively current is being converted to useful work. Lower power factor means higher current for the same real power.

Q2: What are typical power factor values for motors?
A: Induction motors typically have power factors between 0.8-0.9 at full load, lower at partial loads.

Q3: How does voltage affect full load current?
A: Current is inversely proportional to voltage. Higher voltage systems require less current for the same power.

Q4: What if my motor isn't 90kW?
A: This calculator is specifically for 90kW motors. For other sizes, the numerator (90×1000) would change to match the motor's kW rating.

Q5: Is this calculation valid for single-phase motors?
A: No, this formula is for three-phase motors. Single-phase motors use a different calculation without the √3 factor.