Hypertherm HD4070 Rev.8 - Manual (Page 158)

MAINTENANCE
HD4070 Instruction Manual 5-11
1
Initial Checks
Before tracking down specific problems, do a visual check and verify proper voltages are present at the power
source, transformers and power distribution board.
1. Disconnect line power by turning main disconnect switch OFF.
2. Remove top panel, two side panels, front panel and rear panel of power unit.
3. Inspect interior of power unit for discoloration on PC boards, or other apparent damage. If a component or
module is obviously defective, remove and replace it before doing any testing. Refer to the Parts List section to
identify parts and part numbers.
4. If no damage is apparent, plug in the power supply unit, and apply power by turning the main disconnect
switch ON.
(Continued on next page)
WARNING
SHOCK HAZARD: Always use caution when servicing a power supply when plugged in and the covers are
removed. Dangerous voltages exist within the power supply which could cause injury or death.