DC over voltage

What does 7 mean?

The intermediate DC link voltage within the drive has exceeded its maximum permissible limit. This condition can arise from regeneration from the motor, excessive input supply voltage, or very rapid deceleration ramp times, which can stress internal components.

• Rapid deceleration of a high inertia load without adequate braking resistor capacity or dynamic braking enabled (Parameter P2-21).
• External brake resistor either disconnected, open-circuited, or undersized for the application.
• Input supply voltage (L1, L2, L3) exceeding the drive's maximum permissible input voltage (e.g., 480VAC for a 400V drive).
• Faulty or miscalibrated voltage sensing circuit within the drive.
• Motor operating in generator mode (regenerating energy) for extended periods without proper energy dissipation.

Click steps to track your progress.

1. 1

   Measure the AC input supply voltage at the drive's L1, L2, L3 terminals using a multimeter to confirm it is within specification (e.g., 380-480VAC +/-10%).

2. 2

   Verify the connection and resistance of the external braking resistor at the drive's B1, B2 terminals using an ohmmeter, comparing to the rated value.

3. 3

   Increase the deceleration ramp time (Parameter P1-03) to reduce the rate of energy regeneration during stops.

4. 4

   Enable or adjust dynamic braking functionality (e.g., Parameter P2-21, DC Bus Overvoltage Controller gain) if not already active.

5. 5

   If using an active front end (AFE) drive, verify its grid synchronization and regeneration settings are correct.