Troubleshooting & repair – Lincoln Electric POWER MIG 255 SVM144-B User Manual
Page 51
POWER MIG 255
F-13
F-13
TROUBLESHOOTING & REPAIR
11. Turn the machine ON.
12. Make the following voltage tests at plug
J5.
a. Turn the machine OFF between
each test.
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity to perform the test.
c. If the voltage tested is incorrect,
check for loose or broken leads
between the test points and the
main transformer.
d. If the voltage is not corrected, go to
step 16.
13. Turn OFF the machine power.
6. Connect main input power to the
machine.
7. Turn the POWER MIG 255 ON/OFF
POWER SWITCH to ON.
8. Carefully make the following voltage
tests at plug J6.
a. Turn the machine OFF between
each test.
b. Carefully insert the meter probes
into the back of each Molex plug
pin cavity to perform the test.
9. Turn OFF the machine.
10. Locate the following leads on plug J5
on the G3521 control PC board. See
Figure F.1.
MAIN TRANSFORMER TEST (continued)
FROM
LEAD
X5
(6J6)
X5
(6J6)
X6
(5J6)
TO
LEAD
X6
(5J6)
X7
(4J6)
X7
(4J6)
EXPECTED
VOLTAGE
15VAC
30VAC
15VAC
PLUG
LOCATION
16J5
8J5
LEAD
X8
X9
FROM
LEAD
X8
(16J5)
TO
LEAD
X9
(8J5)
EXPECTED
VOLTAGE
115VAC