Undervoltage in power section

What does E8026 mean?

The DC bus voltage in the drive's power section has dropped below the minimum acceptable threshold. This indicates insufficient power available for motor operation.

• Insufficient incoming AC mains voltage (see E2814).
• Excessive load causing a momentary drop in DC bus voltage.
• Faulty rectifier stage or pre-charge circuit in the drive.
• Internal power supply issue within the drive.

Click steps to track your progress.

1. 1

   Measure the incoming AC mains voltage at the drive's input terminals and ensure it is stable and within specified limits.

2. 2

   Check the DC bus voltage at the +UDC/-UDC terminals on the drive during operation and ensure it remains above the undervoltage threshold.

3. 3

   Verify that the drive is correctly sized for the motor and application load, avoiding momentary overloads.

4. 4

   Inspect the pre-charge resistors and contactors/relays for proper functionality if the fault occurs during power-up.