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.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

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

2. 4

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