Tweco Max 300 w-TD-750 - Manual (Page 33)

Manual 0-2557 27 SERVICE
SECTION 5:
CUSTOMER/OPERATOR
SERVICE
5.01 Introduction
This Section describes basic maintenance procedures per-
formable by operating personnel. No other adjustments
or repairs are to be attempted by other than Thermal
Dynamics Trained personnel.
WARNINGS
Disconnect primary power at the source before dis-
assembling the torch or torch leads.
Frequently review the Important Safety Precau-
tions (page 1). Be sure the operator is equipped with
proper gloves, clothing, eye and ear protection.
Make sure no part of the operator’s body comes into
contact with the workpiece while the torch is acti-
vated.
CAUTION
Sparks from the cutting process can cause damage
to coated, painted, and other surfaces such as glass,
plastic and metal.
NOTE
Handle torch leads with care and protect them from
damage.
5.02 General Torch Maintenance
A. Cleaning Torch
Even if precautions are taken to use only clean air with
a torch, eventually the inside of the torch becomes
coated with residue. This buildup can affect the pilot
arc initiation and the overall cut quality of the torch.
WARNINGS
Disconnect primary power to the system before
disassembling 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.
The inside of the torch should be cleaned with electri-
cal contact cleaner using a cotton swab or soft wet
rag. In severe cases, the torch can be removed from
the leads (refer to Section 5.06, Servicing Machine
Torch Components) and cleaned more thoroughly by
pouring electrical contact cleaner into the torch and
blowing it through with compressed air.
CAUTION
Dry the torch thoroughly before reinstalling.
B. Checking Center Insulator
The center insulator separates the negative and posi-
tive sections of the torch. If the center insulator does
not provide adequate resistance, current which is in-
tended for the pilot arc may be dissipated into the
torch head, resulting in torch failure.
WARNINGS
Disconnect primary power to the system before
disassembling 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.
1. Remove the shield cup, tip, gas distributor, and
electrode from the torch. Disconnect the torch leads
from the system to isolate the torch from power
supply circuits.
2. Using an ohmmeter (set to 10K or higher), check
for continuity between the positive and negative
torch quick disconnect fittings. Infinite resistance
(no continuity) should be found. If continuity is
found, refer to Section 5.08, Torch and Leads
Troubleshooting.