Undervoltage in power section

What does E8026 mean?

This warning signifies that the DC bus voltage within the IndraDrive MPx02's power section has dropped below a specified undervoltage threshold. This can lead to reduced motor performance and, if prolonged, can trigger a fault condition to protect the drive from improper operation.

• Insufficient incoming AC mains voltage to the drive.
• Excessive load current demand causing transient DC bus voltage sag.
• High resistance connections in the power supply path (e.g., loose wires, faulty contactors).
• Internal DC bus capacitor degradation, reducing its energy storage capacity.
• Temporary power dip in the mains supply.

Click steps to track your progress.

1. 1

   Measure the incoming AC mains voltage at the drive input terminals (L1, L2, L3) and confirm it is stable and within the drive's specified operating range.

2. 2

   Monitor the actual DC bus voltage through the IndraDrive MPx02's diagnostic interface during operation, especially under peak load conditions.

3. 3

   Inspect all power cable connections, circuit breakers, and contactors in the power supply circuit for tightness and absence of corrosion or damage.

4. 4

   Reduce the dynamic load on the motor or optimize the motion profile to prevent sudden, large current demands that could cause DC bus sag.

5. 5

   Verify that the drive's nominal mains voltage parameter (e.g., P-0-0120) is correctly set to match the actual supply voltage.