Troubleshooting for low DC bus voltage

Diagnostic code 622

Diagnostic code 622 occurs when the Direct Current (DC) bus voltage is too low.

Symptoms

Code Symptoms XPR® models XPR action Code cancels with...
622 The DC bus voltage is less than 280.5 V. All models Shut down Remote on-off

Corrective action

  1. Make sure that the input-line voltage is within ±14% of nominal.

    Refer to General input power requirements.

  2. Remove the power from the cutting system.
  3. Remove the cover from the contactor.
  4. Examine the contacts for excess wear, and replace the contactor if there is excess wear.
  5. Examine the following contactor components for loose connections:
    • Contactor
    • Input to the chopper
    • Power cord
  6. Tighten loose connections if found.
  7. Examine the connections from the control Printed Circuit Board (PCB) on J6:
    1. Look for loose or bad connections on pin 5 and pin 6.
    2. Tighten loose connections, or replace bad connections.
  8. Make sure that Light Emitting Diode (LED) D1 on the power distribution PCB is illuminated.
  9. If D1 is not illuminated, examine the power distribution PCB for:
    • 120 VAC at the input (J1 pin 5 and pin 6)
    • Continuity on fuse FH2 (with power OFF)
    • 120 VAC at the output (J5 pin 7, pin 8, pin 9, and pin 10)
  10. If 120 VAC is not present on the J5 contactor output pins, examine the J4 and K1 relay connections for damage.
  11. If K1 is bad, replace either the power distribution PCB or the K1 relay (003257).
  12. If you cannot find or correct the problem, speak to your cutting machine supplier or regional Hypertherm® Technical Service team.