Troubleshooting & repair, Meter circuit accuracy test (continued) – Lincoln Electric LN-9 SVM127-A User Manual

Page 97

TROUBLESHOOTING & REPAIR

F-39

LN-9 Wire Feeder

METER CIRCUIT ACCURACY TEST

(continued)

Test for AC supply to the meter PC board.

Check for 8 to 11 VAC from lead #601 to
#602. See Figure F.10.

Note: The coating will have to be removed
from the test points.

Test for DC volts on the meter PC board.

Check for 4.75 to 5.25 VDC from TP5 to lead
#510C. See Figure F.10.

NOTE: The coating will have to be removed
from the test points.

If the display is NOT lit and the correct DC volt-
age is present at TP5 to lead #510C, the digital
meter may be faulty. Replace the digital meter.

If AC voltage IS present at leads #601 to #602
and the DC voltage is missing, the meter PC
board may be faulty.

FIGURE F.10 – METER PC BOARD TEST POINTS

561

601

602

510C

517

560

TP5

TP4