Overvoltage During Deceleration

What does -ObF mean?

This fault occurs when the motor generates excessive regenerative energy back into the drive controller's DC bus during rapid deceleration or when driving an overhauling load (e.g., lowering a weight). This rapid increase in DC bus voltage can exceed safe limits and damage the drive's internal components if not dissipated properly.

Complete Troubleshooting Guide

1. 1

   Increase the deceleration ramp time in the drive controller's settings to allow for a slower, controlled stop, reducing regenerative energy.

2. 2

   If the load is highly inertial or overhauling, install an external braking resistor (and braking unit, if required) to dissipate the regenerative energy generated by the motor.

3. 3

   Consider activating the 'brA' (Braking Control) function in the drive's parameters if supported and compatible with the application, as described on page 63, to optimize regenerative energy handling.