Tweco PAK 200i - Manual (Page 78)

PAK 200i
7-10 TORCH INFORMATION Manual 0-5335
B. Reassembling Machine Torch Assembly
NOTE
Verify that the small rubber duck valve is in torch plasma fitting.
1. Remove the rigid insulator from the old Torch Head Assembly from between the layers of Estermat paper.
�. Slide the rigid insulator between the layers of Estermat paper on the replacement Torch Head Assembly (see
NOTE).
NOTE
Over a period of time there may be a breakdown of the Estermat paper causing the Torch Head to short out if the
rigid insulator is not installed.
Two Layers Of
Estermat Paper
Rigid Torch
Leads Insulator A-01577
Figure 7-9: Rigid Insulator Installation
3. Secure the rigid insulator in place with electrical tape.
4. Slide replacement shrink on tubing on leads.
5. Connect the plasma (+), secondary, coolant supply, (-) and coolant return connectors.
6. Secure leads and tubing with single layer of electrical tape.
7. Slide the torch adapter down over the leads and screw the adaptor securely onto the back of the Torch Head
assembly.
8. Slide the positioning tube down over the leads and thread it into the torch adaptor on the Torch Head as-
sembly.
9. Apply tape to the torch leads sleeving at the back end of the positioning tube.
10. Position shrink on tubing over the tape and shrink.
11. Install the front end torch parts.
7.08 Torch And Leads Troubleshooting
A. General Information
Failures in the Torch and Leads can be isolated to the Torch Head or Torch Lead components. To properly isolate
the failed part requires the use of an ohmmeter and a Hi-Pot Tester.
WARNING
The use of a Hi-Pot Tester should be performed only by a qualified electronic technician.
In the Torch Head the center insulator separates the negative and positive charged sections of the torch. If the center
insulator does not provide adequate resistance, current which is intended for the pilot arc may be dissipated into
the Torch Head, resulting in torch failure.