Symptoms, When gun trigger is pulled, there is no wire feed, Troubleshooting guide – Lincoln Electric LN-25 SVM114-C User Manual
Page 42: Troubleshooting and repair, Caution
1. W i t h t h e g u n t r i g g e r c i r c u i t
activated and the mode switch
in the CV position, check for
the presence of 2 to 23 VDC at
leads 539 to 541. This is the
n o r m a l ra n g e fo r a r m a t u r e
voltage, which is dependent on
the wire speed setting.
2. If the normal armature voltage
is present at leads 539 to 541,
t h e n
t h e
m o t o r
o r
m o t o r
brushes may be faulty. Check
or replace.
3. If the correct armature voltage
is missing, then remove any
o p t i o n
p l u g s
t h a t
m ay
b e
connected to J3 on the control
board.
Install the jumper plug
into the J3 receptacle. If the
p r o bl e m i s s o l ve d , t h e n t h e
option board may be faulty.
4. Check the wire speed control,
range switch and associated
wiring to the control board.
5. If the correct armature voltage
is still not present at leads 539
to 541, then the control board
may be faulty. Replace.
FEEDING PROBLEMS
Observe Safety Guidelines
detailed in the beginning of this manual.
Troubleshooting Guide –
See Wiring Diagrams for location of specified
components. See Wiring Diagrams for troubleshooting of specific circuits.
NOTE: Many options and possible option combinations are available for the LN-25™. In many cases, it is
best to disconnect the options and test the LN-25™ in its “basic” form. In this manner, many possible faulty
circuits can be isolated and/or eliminated from the troubleshooting procedure.
F-4
TROUBLESHOOTING AND REPAIR
F-4
LN-25™
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
When gun trigger is pulled, there is
no wire feed.
NOTE:On codes above 10100, the
motor leads (541 & 539) are
in Control Board Connector
J4, pins 13 & 14.
1. Check to see if the drive rolls
a r e
t u r n i n g
w h e n
t h e
g u n
tr igger is pulled. If the dr ive
rolls are turning, then check for
a mechanical restriction in the
wire feed path.
2. If the drive rolls do not tur n,
then check to ensure the power
s o u r c e i s o n a n d a n o p e n
circuit voltage (OCV) is present
at the weld terminals.
3. Make sure the LN-25™ work
clip is connected to the work
piece or work terminal.
4. Ensure the LN-25™ polar ity
switch matches the electrode
polarity.
5. Check if the jumper plug on the
c o n t r o l
b o a r d
o r c o n t a c t o r
b o a r d ( i f u s e d ) i s l o o s e o r
missing.
6. Make certain the power source
open circuit voltage is above 15
V D C bu t n o t m o r e t h a n 1 1 0
VDC.
7. C h e ck i f t h e g u n t r i g g e r i s
faulty. Repair or replace.
8. O n “ o l d e r ” c o n t r o l
b o a r d s,
c h e ck t h e 1 / 8 a m p f u s e. I f
“blown”, the gun may be faulty.
Major physical or electrical damage
is evident when the box cover is
removed.
1. C o n t a c t
L i n c o l n
E l e c t r i c
S e r v i c e D e p a r t m e n t 1 - 8 8 8 -
935-3877.
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely,
contact the Lincoln Electric Service Department for technical troubleshooting assistance before you proceed.
Call 1-888-935-3877.
CAUTION