Inverter Overload shut-off (electronic overcurrent protection)

What does E.THT mean?

This protective function activates to prevent damage to the inverter's output transistors. It triggers when a current exceeding 150% of the inverter's rated output current flows for an extended duration, typically if immediate overcurrent protection (for currents >200%) does not activate. The protection utilizes inverse-time characteristics, with an overload immunity of 150% for 60 seconds, leading to an inverter output stop.

• Inverter output current exceeds the programmed overload limit (P1-18).
• Overheating of the inverter power module due to insufficient cooling.
• Abnormal load conditions on the motor causing excessive current draw.
• Short circuit within the motor or its power leads.

Click steps to track your progress.

1. 1

   Measure the output current from the inverter (terminals U, V, W) to the motor and compare it against the inverter's rated output current.

2. 2

   Evaluate the mechanical load on the motor for any conditions that might cause excessive current draw on the inverter, and reduce the load if necessary.

3. 3

   Inspect the driven equipment for any signs of mechanical binding, excessive friction, or misalignment that could increase the power demand.