1. What is Motor Overload Current?

Motor overload current is the current setting at which a motor's overload protection device should trip to prevent damage from excessive current. The standard calculation uses 125% of the motor's full load amps (FLA).

2. How Does the Calculator Work?

The calculator uses the standard overload current formula:

Where:

• \( FLA \) — Full Load Amps (motor nameplate rating)
• \( 1.25 \) — Standard safety factor (125% of FLA)

Explanation: The 125% factor provides protection against sustained overloads while allowing for normal startup currents.

3. Importance of Proper Overload Protection

Details: Correct overload settings prevent motor burnout from excessive current while allowing normal operation. This protects both the motor and the electrical system.

4. Using the Calculator

Tips: Enter the motor's full load amps (FLA) from its nameplate. The calculator will determine the proper overload setting.

5. Frequently Asked Questions (FAQ)

Q1: Why use 125% of FLA for overload setting?
A: The 125% factor provides a safety margin that protects the motor while allowing for normal operating variations.

Q2: When might I use a different percentage?
A: Some special applications may require different settings, but 125% is standard for most general purpose motors.

Q3: What's the difference between FLA and RLA?
A: FLA (Full Load Amps) is for motors, RLA (Rated Load Amps) is for compressors. They're similar but not identical concepts.

Q4: Does this apply to both single-phase and three-phase motors?
A: Yes, the 125% rule applies to both, though three-phase motors typically have lower FLA for the same horsepower.

Q5: What about motor service factor?
A: Motors with service factor >1.0 may need special consideration - consult manufacturer recommendations.