Lincoln Electric LN-25 Service Manual page 53

F-16
FIGURE F.8 Ð IN-LINE CONNECT ORS BEHIND MYLAR INSULA TION.
DRIVE MOTOR
LEAD IN-LINE
CONNECTOR
HALL EFFECT MODULE
LEAD IN-LINE
CONNECTOR
TEST PROCEDURE
1. Open the case door . Remove the wire
reel by removing the retaining collar
See Figure F .1.
2. Remove the three screws holding the
control box cover in place and remove
the control box cover . See Figure F .1.
3. For codes 10148 and above, separate
the in-line connector (containing the
drive motor leads) located behind the
mylar insulation. Be sure to identify
the correct in-line connector
also an in-line connector for the hall
ef fect module behind the mylar
insulation. See Figure F .8. For codes
9812 and below , remove the two
motor
541(black) from the control PC board.
See Figure F .7.
TROUBLESHOOTING AND REPAIR
WIRE DRIVE MOTOR TEST (continued)
leads 539(white)
4. Apply a variable DC voltage to the
drive motor from lead 541(black)(+) to
lead 539(white)(-).
.
5. When the supply voltage is varied
from 2 to 23 VDC, the drive motor
speed (RPM) should vary accordingly
If the motor does not run or vary in
speed, the motor , gearbox or motor
brushes may be faulty . Check or
replace.
6. Check the resistance between each
of the motor leads [541(black) and
. There is
539(white)] and the motor case.
resistance should be very high (at
least 500,000 ohms). If the resistance
is low , the motor is grounded to the
motor case and should be replaced.
and
LN-25
F-16
.
The