Lincoln Electric X-TRACTOR 3A Service Manual page 24

X-TRACTOR ® 3A
CONTROL TRANSFORMER (TR1) RESISTANCE TEST
PROCEDURE
1. Remove input power to the X-Tractor 3A.
2. Perform the Case Cover Removal Procedure.
3. Locate the control transformer on the DIN rail. See Figure F.3.
4. Using a small slotted screwdriver, label and remove the two
secondary leads from the control transformer (Leads 0 and 24).
See Figure F.4. See the Wiring Diagram.
5. Using a small slotted screwdriver, label and remove the two
primary leads from the control transformer (Leads 0 and 460).
Lead numbers will vary with 230 Volt X-Tractor 3A machine.
See Figure F.4. See the Wiring Diagram.
6. Check the resistance of the 24 Volt secondary winding in the
control transformer. Normal resistance is approximately 0.2 ohms.
This resistance may vary if testing an 230 Volt X-Tractor 3A
machine.
7. Check the resistance of the 460 Volt primary winding in the
control transformer. Normal resistance is approximately 61 ohms.
This resistance may vary if testing an 230 Volt X-Tractor 3A
machine.
8. Check the resistance between the primary and secondary
windings. Normal resistance should be at least 500,000 ohms.
9. Also check the resistance from the primary and secondary
windings to ground. Normal resistance should be at least 500,000
ohms to ground.
(460V MACHINE)
Figure F.3 – Control transformer location
TRANSFORMER
(LOCATED ON DIN RAIL)
10. If further testing is required carefully apply the correct input
11. Connect all leads previously removed.
12. Perform the Case Cover Replacement Procedure.
F-10
TROUBLESHOOTING AND REPAIR
(continued)
voltage (230VAC or 460VAC) to the correct primary terminals of
the control transformer and verify that 24VAC is being generated
at the secondary terminals of the control transformer.