Tweco XTTM-301 - Manual (Page 63)

Manual 0-4768 5-9 SERVICE
F. No gas flow
1. Gas not connected or pressure too low
a. Check source for proper input pressure.
2. Faulty components in torch and leads assembly
a. Inspect torch assemblies and replace if neces-
sary. Refer to Section 5.07, Torch and Leads
Troubleshooting.
3. Faulty components in power supply system components
a. Return for repair or have qualified technician
repair per Service Manual.
G. Torch cuts but not adequately
1. Current set too low at power supply
a. Increase current setting
2. Torch is being moved too fast across workpiece
a. Reduce cutting speed (refer to Cutting Speed
Charts in the Appendix).
3. Excessive oil or moisture in torch
a. Hold torch 1/8 inch (3 mm) from clean surface
while purging and observe oil or moisture
buildup (do not activate torch)
4. Torch tip contacting workpiece
a. Increase standoff distance
5. Torch tip worn
a. Replace tip
6. Wrong gas pressure
a. Set correct gas pressure
5.06 Servicing Torch Components
WARNINGS
Disconnect primary power to the system before dis-
assembling the torch or torch leads.
DO NOT touch any internal torch parts while the
AC indicator light on the front panel of the Power
Supply is ON.
A. Removing Torch Head
1. Remove the shield cup, cartridge, and consumables
from the torch head.
2. Locate the shrink-on tubing at the back end of the
torch positioning tube. Remove the shrink-on tub-
ing from the torch lead sleeving being careful not
to damage the lead assembly underneath.
3. Under the shrink-on tubing remove the tape from
the torch lead sleeving and slide the sleeving back
(see NOTE).
NOTE
The positioning tube will not slide over the torch
lead sleeving.
4. Unscrew the positioning tube from the torch head
assembly and slide the positioning tube back over
the leads to expose the plasma (+), secondary
(shield), coolant supply (-), and coolant return
connectors.
CAUTION
Hold the torch head stationary and unscrew the
positioning tube. Do not unscrew the torch head.
Do not let the torch leads or connectors twist.
5. Disconnect the plasma (+), secondary (shield), cool-
ant supply (-), and coolant return connectors to
allow removal of the torch head. Note the location
of the torch leads insulator between the negative
and positive leads.