Hypertherm HPR800XD Auto Gas Rev.2 - Manual (Page 223)

Maintenance
HPR800XD Auto Gas – 806500 5-9
Power supply troubleshooting
If one of the power supplies in an HPR800XD system fails, the system can still be used for cutting with processes up
to 400 amps. The primary and secondary power supplies are identical except for the control board. The power supply
control boards can not be interchanged.
If the secondary power supply fails, turn OFF the main disconnect to the secondary power supply, and use the system
as a 400 amp system. All power to the secondary power supply must be turned off.
If the primary power supply fails, use parts (except the control board) from the secondary power supply to fix the primary
power supply. The system can now be used as a 400 amp system.