Thermal Dynamics CUTMASTER 81, Service Manual

Page: 50 / 88

REPLACEMENT PROCEDURES 5-10 Manual 0-2957
9. Connect wires as follows.
From Output
Diode A
Terminals
To Power
Output
PCB Terminal
From Output
Diode B
Terminals
To Power
Output
PCB Terminal
E34, E39 E37 E34, E39 E36
E48, E50 E47 E48, E50 E45
E56, E60 E58 E56, E60 E57
E53, E54 E52 E53, E54 E49
Output Diode A Output Diode B
CutMaster 81 Output Diode Connections
E. Output Power PC Board Replacement
Follow the antistatic procedures in subsection 5.02.
1. Remove cover per subsection 5.04-A.
2. Locate the Power Output PC Board, mounted to
the Heatsink Shroud.
3. Carefully remove all wire connections to the Out-
put Diodes.
4. Straighten the Output Diode wires to be perpen-
dicular to the Output Power PC Board.
5. Label, then disconnect all other wire connections
to the Output Power PC Board. Refer to Appen-
dix 10 for output power PC Board wiring details.
6. Remove the bolts at the top left and bottom right
corners of the Output Power PC Board.
Art # A-03166
Screw Locations
7. Lift the Output Power PC Board off its supports,
and set aside.
8. Install the replacement Output Power PC Board
by reversing the above steps.
9. Note that the output power PC Board includes a
jumper wire between studs E58 and E57. Refer
to Appendix 10 for output power PC Board wir-
ing details.
F. Heatsink Shroud Assembly Removal
The Heatsink Shroud Assembly must be disengaged for
access to either the Main Transformer or the Output In-
ductor. Follow these steps for access to either compo-
nent.
1. Remove the Power Supply cover per subsection
5.04-A.
2. Release the tab on the vertical face of the Heat-
sink Shroud securing the Solenoid/Pressure
Switch Assembly in position.
3. Remove the gas hose from the Regulator Fitting
on the back panel of the Power Supply by press-
ing on the locking ring on the elbow fitting, while
pulling on the hose.
4. Remove the Power Supply Back Panel per sub-
section 5.07-D.
Remove the grommets from the two holes on the
right (rear) edge of the Heatsink Shroud.
5. Remove the Fan Assembly per subsection 5.08C.
6. Label and disconnect the wires connected to the
Pilot PC Board.
7. Remove the hardware securing the Pilot PC Board
in place. Pull the PC Board off the center chassis.
8. Label and disconnect wires No. 45, 47, 49, and 52
from the Power Output PC Board.
9. Disconnect the wires from the Output Inductor
to terminal E43 on the Power Output PC Board.
Disconnect the torch receptacle ground wire con-
nected to the center chassis.
10. Remove nuts on two studs at the top corners of
the Heatsink Shroud, and nuts on two studs on
the bottom flange of the Heatsink Shroud.
12. Remove the Heatsink Shroud as follows:
a. Use the open left end of the Heatsink Shroud
and the Pressure Switch/Solenoid opening as
handles.
b. Pull the Heatsink Shroud away from the cen-
ter chassis, and then up. It may be necessary
to pry the top and bottom flanges of the Heat-
sink Shroud slightly to release them from their
mounting studs. Movement will be limited
by the wiring harness.