Overvoltage

What does OV mean?

This fault occurs when the DC bus voltage inside the inverter exceeds a permissible threshold. It is commonly caused by regenerative energy from the motor during rapid deceleration, an unstable input power supply, or a malfunctioning braking resistor. Sustained overvoltage can damage the inverter's DC link capacitors and power components.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Check the braking resistor and braking unit (if installed) for proper wiring and functionality, ensuring resistance values are correct.

2. 4

   Confirm that the motor is not being driven externally (overspeeding) by the load, forcing regeneration.

3. 5

   Inspect for loose connections in the input power circuit or DC bus.