Tweco RAS used w-Merlin 6000GST - Manual (Page 23)

Manual 0-2654 19 SERVICE
SECTION 4:
CUSTOMER/OPERATOR
SERVICE
4.01 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.
WARNING
Disconnect primary power at the source before
opening the Arc Starter Box Assembly.
4.02 General Maintenance
The only routine maintenance required for the Arc Starter
Box is a thorough cleaning and inspection, with the fre-
quency depending on the usage and the operating envi-
ronment.
To clean the Arc Starter Box, first make sure that the
power is disconnected. Open the Arc Starter Box enclo-
sure and blow out any accumulated dirt and dust with
compressed air. The unit should also be wiped clean. If
necessary, solvents that are recommended for cleaning
electrical apparatus may be used.
While the enclosure is open, inspect the wiring in the
unit. Look for any frayed wires or loose connections
that should be corrected.
4.03 Troubleshooting Guide
A. Troubleshooting
This Sub-Section covers troubleshooting that requires
disassembly and electronic measurements. It is helpful
for solving many of the common problems that can arise
with this torch assembly.
NOTE
Refer to Appendix I for the Interconnecting Dia-
gram of the Arc Starter Box.
B. How to use this Guide
The following information is a guide to help the Cus-
tomer/Operator determine the most likely causes for
various symptoms.
This guide is set up in the following manner:
X. Symptom (Bold Type)
Any Special Instructions (Text Type)
1. Cause (Italic Type)
a. Check/Remedy (Text Type)
Locate your symptom, check the causes (easiest listed
first) then remedies. Repair as needed being sure to
verify that unit is fully operational after any repairs.
A. Start signal given to the Power Supply. Gas
flows for selected pre-flow time then Pilot LED
flashes momentarily. DC LED is OFF, does not
even come ON momentarily.
1. Problem not in the Arc Starter Box. The Power Sup-
ply is has no DC voltage output.
a. Refer to the Power Supply Service Manual to
test the output of the Power Supply
B. Start signal given to Power Supply. Gas flows for
selected pre-flow time then Pilot and DC LEDs
are ON steady. Pilot doesn't come ON but there
is a spark (repetitive snapping sound) from the
spark gap in Arc Starter Box.
For the spark gap to fire, the Power Supply DC out-
put has to be getting to the Arc Starter Box.
1. Consumable Torch parts are shorted
a. Check or replace the consumable Torch parts
2. Arcing or burning inside Torch Head Assembly
a. Remove the consumables from the Torch Head
Assembly and check for signs of arcing or burn-
ing inside the torch head. Replace Torch Head
Assembly if required.
3. Arcing or burning between the Torch fittings or from
the fittings to the Mounting Tube
a. Remove the Torch Head Assembly from the
mounting tube and check for arcing or burn-
ing between the fittings or from the fittings to
the tube. Repair as required.
4. Defective CD transformer
a. Check for arcing around the CD Transformer
(while spark gap is firing) and look for any
cracks in the ferrite cores. If either problem
exists replace the CD Transformer.