Lincoln Electric IM697 RED-D-ARC MX 300 - Manual (Page 24)

E-4 TROUBLESHOOTING E-4
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
(SYMPTOMS)
POSSIBLE AREAS OF
MISADJUSTMENT(S)
RECOMMENDED
COURSE OF ACTION
The meter is not accurate:
Fan does not run when turning
machine on:
Fan does not run when welding:
No control, very high output cur-
rent:
No control, maximum output cur-
rent stays around 200A:
No control :
1. The Analog Control Power Supply
PCB or its connections may be
faulty.
2. The Weld Control PCB may be
faulty.
1. Fan does not normally run until
machine is welding. See
Instruction Manual.
1. Faulty Supply voltage to fan, nor-
mal is 40 VDC.
2. Replace fan if supply voltage to
fan is good.
3. The Weld Control PCB may be
faulty.
1. Check input & output cables.
Check connections at (+) Input
stud & (+) Electrode stud, make
sure they donʼt short to case.
2. Faulty shunt lead connection.
3. Faulty output control potentiome-
ter or its connections.
4. Faulty Weld Control PCB.
1. Check output cables. Check con-
nections at (+) Electrode stud and
Work.
2. Faulty voltage feedback connec-
tion. Check continuity from lead
#401 at C1 to lead #301 at pin 1
of P22 (refer to wiring diagram).
3. Faulty Weld Control PCB.
1. Faulty output control potentiome-
ter or its connections.
2. Faulty connections at Weld
Control PCB connectors.
3. Faulty Weld Control PCB.
If all recommended possible areas of
misadjustment have been checked
and the problem persists, Contact
your local Authorized Field
Service Facility.
RED-D-ARC MX350