Motor Overload Protection

What does E05 mean?

This fault occurs when the inverter's electronic thermal protection detects that the motor is operating under an excessive load, causing it to overheat. The inverter calculates the motor's thermal state based on current and time, tripping to prevent motor damage from prolonged overload.

• Continuous operation of the motor above its rated current due to excessive mechanical load on the driven equipment.
• Insufficient motor cooling (e.g., blocked fan, high ambient temperature, contaminated cooling fins).
• Motor thermal protection parameters (e.g., P1-03 Motor rated current, P1-05 Motor overload protection level) incorrectly set.
• Voltage imbalance across the three phases of the inverter output, leading to localized heating in the motor windings.
• Long motor cable runs without appropriate cable compensation settings (e.g., P1-06 Motor cable compensation), causing voltage drop and increased current.

Click steps to track your progress.

1. 1

   Measure motor current (display parameter d0-03) and compare it against the motor nameplate rated current during normal operation.

2. 2

   Check the motor's cooling fan and cooling fins for obstructions or excessive dust buildup; ensure proper airflow.

3. 3

   Verify that Parameter P1-03 (Motor rated current) and P1-05 (Motor overload protection level) are accurately set according to motor specifications.

4. 4

   Measure the voltage balance across inverter output terminals U, V, W using a multimeter, ensuring phase voltages are within 2% of each other.

5. 5

   Reduce the mechanical load on the motor if operating current consistently exceeds the motor's rated current or redesign the system.