LV4-Trip (Undervoltage in intermediate circuit while charging, 500 V threshold not reached)

What does 124 mean?

This fault indicates an undervoltage condition in the intermediate DC bus circuit during charging, specifically failing to reach the 500V threshold (KPS-600). This suggests an issue with the incoming mains supply or the rectifier section, preventing the DC bus from charging adequately for operation.

• LV4-Trip: Intermediate circuit undervoltage during charging (500V threshold not reached) (P1-21).
• Main DC bus voltage is too low during the charging phase.
• Failure of the pre-charge resistor or relay.
• Low input voltage to the drive.

Click steps to track your progress.

1. 1

   Measure the incoming AC mains voltage at the drive input terminals.

2. 2

   Measure the DC bus voltage at terminals +UDC/-UDC during the charging attempt.

3. 3

   Verify the integrity of the rectifier section of the drive for any component failures.