DC Bus Overvoltage

¿Qué significa DC Overvoltage ?

The DC bus voltage inside the drive has risen beyond its acceptable operating limit. Common causes include excessively short deceleration times, disabled stall prevention, a malfunctioning braking chopper or resistor, unstable motor control, or an excessively high input voltage. This condition poses a risk of damage to the drive's internal DC link capacitors and power components.

• Deceleration time (e.g., P1-06) is set too short for the inertia of the load, causing excessive regenerative energy.
• Braking resistor (if installed) is incorrectly sized (too high resistance), disconnected, or its braking chopper circuit (internal or external) has failed.
• 'Stall Prevention (Decel)' function (e.g., L3-04) is disabled or set too low, preventing the drive from extending deceleration time.
• High inertia load application experiencing rapid speed reduction, overpowering the drive's regenerative braking capacity.
• Input supply voltage (e.g., L1, L2, L3) is intermittently or continuously too high, exceeding the drive's nominal input voltage range (e.g., 400V).

Haga clic en los pasos para seguir su progreso.

1. 1

   1. Increase the deceleration time parameter (e.g., P1-06) by at least 20% to allow for slower energy dissipation from the load.

2. 2

   2. Enable and properly configure the 'Stall Prevention (Decel)' function (e.g., L3-04) to allow the drive to automatically extend deceleration time and prevent overvoltage.

3. 3

   3. If a braking resistor is installed, verify its resistance value with an ohmmeter (e.g., X ohms) matches the drive's specifications and check wiring to terminals (e.g., B1, B2).

4. 4

   4. Check the functionality of the internal or external braking chopper. Monitor the DC bus voltage (U1-03) during deceleration to see if the chopper activates.

5. 5

   5. Measure the incoming AC line voltage (e.g., between L1-L2, L2-L3, L3-L1) with a multimeter to ensure it is within the drive's specified operating range.

6. 6

   6. For high inertia loads, consider installing an appropriately sized external braking resistor and chopper if not already present, or increasing the existing one's capacity.