3-9
M
AINTENANCE
Service Manual
WARNING
SHOCK HAZARD: Do not attempt repairs on the power board or control
board. Do not in any way cut away or remove the protective conformal
coating from either board. To do so will risk a short between the AC input
circuit to the output circuit and may cause serious injury or death.
The power supply and PC boards are subjected to dielectric and insula-
tion resistance tests per applicable CSA and IEC standards for the safety
of the operator and service technicians.
Removal of the protective conformal coatings and other unauthorized
repairs to the PC boards will void the warranty.
If questions or problems arise during servicing, call the Hypertherm Tech-
nical Services department at 1-800-643-9878.
1.
Set the Powermax800 power switch to O (off), unplug the power cord, and disconnect the
gas supply - see warnings.
2.
Remove the cover of the power supply by removing 22 securing screws.
3.
Visually inspect the inside of the power supply, especially on the side with the power board
(see Figures 4-2 and 4-3). Look for broken or loose wiring connections, burn and char
marks, damaged components, etc. Repair or replace as necessary.
Initial Resistance Checks
1.
After visually inspecting the exterior and interior of the power supply, always perform the
initial resistance checks before applying power to the power supply. If these checks are not
performed prior to power up, further damage to the power supply could result.
2.
Perform the initial resistance checks beginning on the following page.
3.
After the problem has been located and repaired, refer to the
Sequence of Operation flow
diagram in this section to test the power unit for proper operation.