Lincoln Electric INVERTEC POWER WAVE 450 SVM112-B Service Manual page 252

F-192
FET MODULE REMOVAL AND REPLACEMENT (continued)
PROCEDURE
1. Remove main input supply power to the
machine.
2. With the 3/8" nut driver, remove the 4
screws that hold the handle to the machine.
3. Remove the rubber gasket (cover seal) from
the lift bail.
4. With the 5/16" nut driver, remove the sheet
metal screws from the case top.
5. With the 5/16" nut driver, remove the
screws holding the right and left case sides.
Remove the case sides by lifting up and
out.
6. Perform the Capacitor Discharge Proce-
dure described earlier in this section of the
manual.
TROUBLESHOOTING & REPAIR
FIGURE F.73 - FET MODULE LOCATION
POWER WAVE 450
1. FET MODULE
2. PIEZO ALARM BUZZER
3. FET MODULE LOCKING BAR
4. RESISTORS
WARNING
Before continuing with the
test procedure, perform the
capacitor discharge proce-
dure to avoid electric shock.
7. After you have completed the capacitor dis-
charge procedure for all four switch boards,
use the 5/16" nut driver to remove the two
screws holding the printed circuit board
cover in place. Slide the cover forward and
lift up to remove it.
CAUTION
Be sure to follow the recommended static-free
methods for handling printed circuit boards.
Failure to do so can result in permanent dam-
age to the equipment.
8. Remove the molex plugs from the PC
boards except the display board.
F-192