Regenerative Overvoltage Trip During Deceleration

What does E.OV3 mean?

This fault occurs when the DC bus voltage in the FR-A800 inverter exceeds a permissible limit during deceleration, due to regenerative energy from the motor returning to the DC bus. This typically happens when the deceleration time is too short or the braking capacity (resistor or other means) is insufficient to dissipate the regenerative energy.

• Deceleration time (F011 (Pr.8)) is set too short, causing rapid energy regeneration.
• Insufficient braking resistor capacity or the braking resistor is disconnected/faulty.
• The load has high inertia and is decelerated rapidly.
• Magnetic flux vector control is not selected, leading to less efficient braking.
• Power supply voltage is abnormally high, reducing the headroom for regenerative voltage.

Click steps to track your progress.

1. 1

   Increase the deceleration time (F011 (Pr.8)) to allow for slower dissipation of regenerative energy.

2. 2

   Verify the braking resistor capacity matches the FR-A800 inverter and application requirements. Check its connections and resistance value.

3. 3

   If using magnetic flux vector control, ensure it is enabled, as it can improve braking performance.

4. 4

   Check the incoming power supply voltage to ensure it is within the FR-A800 inverter's specified range.

5. 5

   Consider adding an external braking unit or increasing the braking resistor capacity if the application requires rapid deceleration of high inertia loads.