Hypertherm Powermax1250 Service Manual - Manual (Page 73)

4
MAINTENANCE
3-40 powermax1250 Service Manual
Power board removal and replacement
It may be necessary to remove the power board from the power supply to replace it or to replace components, such
as IGBTs, located behind it.
CAUTION
STATIC ELECTRICITY CAN DAMAGE CIRCUIT BOARDS
Use proper precautions when handling printed circuit boards.
• Store PC boards in anti-static containers.
• Wear a grounded wrist strap when handling PC boards.
Removal
1. Disconnect the electrical power and the gas supply.
2. Remove the cover from the power supply by removing the 12 screws and then lifting off the cover.
3. Remove the insulation panel by removing the screws on the right edge and bottom edge.
4. Disconnect the torch lead and then remove the ETR barrier.
5. Disconnect the pilot arc gate drive and the IGBT gate drives from the power board. Then remove the nuts that
attach the work lead and power cord ground cable to the power board.
Pilot arc gate
drive (J12)
Work lead and ground
cable attachments
IGBT gate drives
(J6, J7 and J8)