Advanced Troubleshooting; Pre Power-Up Checks; Initial Setup Conditions; Primary Power Test - Thermal Arc Fabricator 140 Service Manual

ADVANCED TROUBLESHOOTING

6.01 Pre Power-Up Checks

1. Perform Rectifier Assembly Test Procedure section
6.11.
2. Perform C1 & C2 Test Procedure Section 6.13.
3. Check the F1 fuse. Replace if open.

6.02 Initial Setup Conditions

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
identify the possible symptom(s) and the defective circuit.
After repairs are complete, run the following tests again
to verify that the unit is fully operational.
A. Connect the gas supply to the rear of the Power Supply.
B. Adjust the inlet pressure to approximately 20 CFH.
Refer to page 3-4 "Adjusting Regulator".
C. Set the power supply controls as follows:
1. VOLTAGE CONTROL SWITCH SW1 to Position 0.
2. WIRE SPEED CONTROL Potentiometer to 0 (Fully
Counter Clockwise).
3. Connect work cable to negative (-) Polarity Change
Over terminal.
4. Disconnect the wire from the Feed Head assembly
from the positive (+) Polarity Change Over
terminal.
5. Open the PRESSURE ADJUST DEVICE so the wire
will not feed.
6. With the Primary Line Disconnect in the OFF
position, plug the input power cord into the
primary line outlet.
January 25, 2008
SECTION 6:
ADVANCED TROUBLESHOOTING

6.03 Primary Power Test

A. Close the Primary Line Disconnect and observe the
following:
1. Unit should remain off, nothing happens.
B. Turn VOLTAGE CONTROL SWITCH to position 1 and
observe the following:
1. Green AC LED turns on.
2. Fan turns on.
3. OVERTEMP LED is off.
4. Output Voltage measures 0 VDC.
This completes the Primary Power Test. If the above steps
were correct, proceed to the next section, Logic and
Control Test. If the unit does not function as detailed
above, note the symptom and proceed to Section 6.08
Primary Power Problems.
6.04 Logic & Control Test
A. Close the MIG gun switch.
1. Gas flows.
2. Feed roll turns slowly.
3. Output Voltage measures 21 VDC.
B. Release the MIG Gun Switch.
1. Gas flow stops.
2. Feed roll stops turning.
3. Output Voltage slowly decreases to 0 VDC.
C. Disconnect one of the wires connected to the
temperature switch located on the rectifier heat sink:
1. Yellow OVERTEMP LED turns on.
D. Close the MIG gun switch and observe the following:
1. Gas does not flow.
2. Feed roll does not turn.
3. Output Voltage measures 0 VDC.
6-1
FABRICATOR 140, 180
Manual 0-4992