Troubleshooting & repair, Pc board troubleshooting procedures, Warning – Lincoln Electric IDEALARC DC 1000 SVM123-A User Manual
Page 43
IDEALARC DC-1000
F-3
TROUBLESHOOTING & REPAIR
F-3
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CAUTION: Sometimes machine failures appear to
be due to PC board failures. These problems can
sometimes be traced to poor electrical connections.
To avoid problems when troubleshooting and
replacing PC boards, please use the following pro-
cedure:
1.
Determine to the best of your technical ability
that the PC board is the most likely component
causing the failure symptom.
2.
Check for loose connections at the PC board to
assure that the PC board is properly connect-
ed.
3.
If the problem persists, replace the suspect PC
board using standard practices to avoid static
electrical damage and electrical shock. Read
the warning inside the static resistant bag and
perform the following procedures:
P.C. Board can be damaged by static electricity.
- Remove your body’s static
charge before opening the
static-shielding bag. Wear an
anti-static wrist strap. For
safety, use a 1 Meg ohm
resistive cord connected to a
grounded part of the equip-
ment frame.
- If you don’t have a wrist
strap, touch an unpainted,
grounded, part of the equip-
ment frame. Keep touching
the frame to prevent static
build-up. Be sure not to touch
any electrically live parts at
the same time.
- Tools which come in contact with the P.C. Board
must be either conductive, anti-static or static-dissi-
pative.
ELECTRIC SHOCK can kill.
Have an electrician install and
service this equipment. Turn
the input power OFF at the
fuse box before working on
equipment. Do not touch elec-
trically hot parts.
- Remove the P.C. Board from the static-shielding
bag and place it directly into the equipment. Don’t
set the P.C. Board on or near paper, plastic or
cloth which could have a static charge. If the P.C.
Board can’t be installed immediately, put it back in
the static-shielding bag.
- If the P.C. Board uses protective shorting
jumpers, don’t remove them until installation is
complete.
- If you return a P.C. Board to The Lincoln Electric
Company for credit, it must be in the static-shield-
ing bag. This will prevent further damage and
allow proper failure analysis.
4.
Test the machine to determine if the failure
symptom has been corrected by the replace-
ment PC board.
NOTE: It is desirable to have a spare (known
good) PC board available for PC board trou-
bleshooting.
NOTE: Allow the machine to heat up so that all
electrical components can reach their operating
temperature.
5.
Remove the replacement PC board and sub-
stitute it with the original PC board to recreate
the original problem.
a.
If the original problem does not reap-
pear by substituting the original board,
then the PC board was not the prob-
lem. Continue to look for bad connec-
tions in the control wiring harness,
junction blocks, and terminal strips.
b.
If the original problem is recreated by
the substitution of the original board,
then the PC board was the problem.
Reinstall the replacement PC board
and test the machine.
6.
Always indicate that this procedure was fol-
lowed when warranty reports are to be submit-
ted.
NOTE: Following this procedure and writing on the
warranty report, “INSTALLED AND SWITCHED PC
BOARDS TO VERIFY PROBLEM,” will help avoid
denial of legitimate PC board warranty claims.
PC BOARD TROUBLESHOOTING PROCEDURES
ATTENTION
Static-Sensitive
Devices
Handle only at
Static-Safe
Workstations
Reusable
Container
Do Not Destroy
WARNING