DC Bus Overvoltage

What does ObF mean?

The DC bus voltage inside the drive has exceeded its safe operating limit. This is most commonly caused by regenerative energy from the motor, particularly during rapid deceleration of high-inertia loads, or by an excessively high incoming line voltage. Unresolved overvoltage can lead to damage to the drive's internal power components.

Complete Troubleshooting Guide

1. 1

   Measure the incoming line voltage to ensure it is within the drive's specified operating limits.

2. 2

   Increase the deceleration time of the motor ramp to reduce the amount of regenerative energy fed back to the drive.

3. 3

   If high-inertia loads are present and rapid deceleration is required, consider installing a braking resistor or dynamic braking unit.

4. 4

   Verify that the motor is not being driven by the load (overhauling) when the drive is commanded to stop or decelerate.