DC overvoltage

What does 7 mean?

If the intermediate circuit voltage exceeds its critical limit, the frequency converter will trip after a time delay. This fault often occurs due to regenerative braking, sudden load changes, or issues with the mains supply. Repeated overvoltage trips can damage the drive's power components.

• DC link voltage exceeding its critical hardware limit due to severe regenerative braking.
• Extremely rapid deceleration of a high inertia load combined with insufficient or absent braking resistance.
• Failure of the internal or external braking chopper circuit, preventing dissipation of regenerative energy.
• Excessively high incoming AC mains voltage supplied to the frequency converter's input terminals.

Click steps to track your progress.

1. 1

   Measure the actual AC input voltage at terminals L1, L2, L3 to confirm it is within the specified range for the drive.

2. 2

   Increase the deceleration ramp time in parameter P3-42 (Ramp Down Time 1) or P3-43 (Ramp Down Time 2) to allow smoother load deceleration.

3. 3

   Verify the connection and resistance (in Ohms) of the external braking resistor; replace if open circuit or incorrect value.

4. 4

   Check the internal braking chopper transistor and associated circuitry for faults; measure gate drive signals if applicable (power OFF, discharged).