Thermadyne CE CutMaster 75, Service Manual

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Manual 0-2869 5-13 SERVICE
H. 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 Fan Shroud that secures the
Bulkhead in position. Pull the Bulkhead upward
to release the Bulkhead tabs from the slots on the
Center Chassis.
3. Release the tab on the vertical face of the Heatsink
Shroud securing the Solenoid/Pressure Switch As-
sembly in position.
4. 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.
5. Remove the Power Supply Back Panel per subsec-
tion 5.07-D.
6. Remove the grommets from the two holes on the
right (rear) edge of the Heatsink Shroud.
7. Remove the Fan Assembly per subsection 5.08C.
8. Label and disconnect the wires from the CD Trans-
former to the CD PC Board.
9. Remove the hardware securing the Pilot Control
Relay in place. Pull the Relay and its dust cover
off the center chassis. Set the dust cover aside.
10. Label and disconnect wires No. 45, 49, 47, and 52
from the Power Output PC Board.
11. Disconnect the wires from the Output Inductor to
terminal E43 on the Power Output PC Board.
12. Disconnect the ground wire connected to the cen-
ter chassis between the Pilot Control Relay and the
CD PC Board.
13. 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.
14. 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.
c. Ensure that the top edge of the Shroud does
not hit the bottom edge of the CD PC Board.
Stand the Heatsink Shroud Assembly against
the Power Supply.