Manual 0-2725 4-3 SERVICE TROUBLESHOOTING
C. How to use the Troubleshooting Guide
The following information is a guide to help the Service
Technician determine the most likely causes for various
symptoms. This guide is set up in the following manner:
1. Perform operational check(s) on the equipment to iso-
late problem to possible circuit(s) per Section 4.05,
Circuit Fault Isolation.
2. Determine symptom and isolate to defective assem-
bly using the following format:
X. Symptom (Bold Type)
Any Special Instructions (Text Type)
1. Cause (Italic Type)
a. Check/Remedy (Text Type)
3. Locate your symptom in the appropriate Sub-Section.
4. Check the causes (easiest listed first) for the symptom.
5. Check the remedies listed for each cause.
6. Repair as needed being sure to verify that unit is fully
operational after any repairs.
NOTES
Many signals are transferred between Printed Cir-
cuit Board Assemblies on Ribbon Cables. If these
cables become faulty they can then cause various
problems. Do not forget about these cables when
troubleshooting.
While troubleshooting visually inspect the inter-
nal components for signs of over heating, fractures
and damage.
4.05 Circuit Fault Isolation
NOTE
Follow all instructions as listed and complete each
in the order presented.
This section is to help isolate the defective circuit before
troubleshooting, identify symptoms, and test the unit for
proper operation. Follow the instructions as given to iden-
tify the possible symptom(s) and the defective circuit.
After repairs are complete then run the following tests
again to verify that the unit is fully operational.
A. Initial Setup Conditions
Connect gas supply to rear of Power Supply.
Turn on gas supply and adjust Power Supply Gas Regu-
lator to 60 psi (4.1 bar).
Set the Power Supply controls as follows:
ON/OFF switch to OFF.
RUN/SET switch to SET.
CURRENT control potentiometer to maximum.
B. Main Input and Internal Power Tests
Connect main AC power to the unit.
Set the Power Supply ON/OFF switch to ON and note
the following:
• AC indicator blinks for six seconds, then steady
ON.
• Main Contactor energizes (clicks) while AC indi-
cator is blinking.
• Relay on Input PC Board energizes (clicks) after
AC indicator stops blinking.
• TEMP indicator OFF.
• GAS indicator ON.
• Gas flows.
• Fans will operate.
• DC lndicator is OFF.
Set the Power Supply RUN/SET switch to the RUN posi-
tion and note the following:
• Gas indicator goes OFF.
• Gas flow stops.
This completes the Main Input and Internal Power Tests.
If the above are all correct then proceed to paragraph 'C'.
If the above does not function as noted then note the
symptom and proceed to Section 4.06, Main Input and
Internal Power Problems.
C. Pilot Arc Test
Press the torch switch to establish a pilot arc and note the
following:
• Gas flows.
• GAS indicator turns ON.
• After preflow delay DC indicator turns ON.
• Pilot arc establishe.d
This completes the Pilot Arc Test. If the above are all cor-
rect then proceed to paragraph 'D'.
If the above does not function as noted then note the
symptom and proceed to Section 4.07, Pilot Arc Problems.
To Next Page
Loading...
Need help?
General
