Lincoln Electric IDEALARC R3R-300 - Manual (Page 19)

D-7 TROUBLESHOOTING D-7
IDEALARC® R3R, -300, -400, -500
Low
output,
low
OCV
,
or
erratic
welding
T
urn
control
pot.
to
minimum
Check
OCV
OCV
is
35-55V
OCV
is
40-45V
OCV
is
0
Rated
OCV
but
OCV
less
than
rated
erratic
welding
but
more
than
55V
OCV
45-55V
OCV
35-45V
Possible
machine
Check
leads
76,
77,
Possible
Loose
lead
Possible
intermittent
Possible
Possible
wrong
connection
Possible
defective
is
being
212,
213,
210,
21
1
defective
connections
or
loose
connections
defective
of
gate
leads
if
recent
PC
board
single
phased
&
SW2
for
open
PC
board
on
shunt
in
control
circuit.
PC
board
PC
board
or
rectifier
Check
aux.
voltages
Check
PC
board
con-
stack
change.
on
PC
board
nector
,
switches,
potentiometers,
etc.
201-202
=
120V
±
10%
Replace
Retighten
Replace
See
wiring
diagram
Replace
201-202
=
120V
±
10%
leads
and
correct
202-203
=
120V
±
10%
Remove
and
replace
Gate
leads
G-1,
G-2,
G-3
from
PC
board
one
at
a
time.
If
aux.
voltages
are
incorrect,
If
aux.
voltages
If
removing
each
gate
lead
If
removing
and
replacing
check
&
repair
.
are
OK
one
at
a
time
changes
OCV
each
gate
lead
one
at
a
time
does
NOT
change
OCV
Codes
below
9500
with
power
of
f,
remove
leads
from
Identify
gate
lead
that,
when
Codes
above
9500
75,
76,
77
terminal
strip
and
removed,
OCV
did
not
change.
with
power
of
f,
disconnect
welding
leads
from
output
terminals
Remove
gate
lead.
V
oltage
remote
control
amphenol
between
gate
lead
and
204
must
be
13-17V
.
and
welding
leads
from
output
terminals.
Check
resistance
of
each
If
voltage
OK
If
voltage
is
terminal
on
this
terminal
not
correct
strip
to
ground.
Resistance
Check
the
following
pins
must
be
as
follows:
Defective
power
SCR
for
resistance
to
ground.
75-GND
2K
minimum
Possible
defective
Resistance
must
be
as
76-GND
2K
minimum
PC
board
follows:
77-GND
12K
minimum
Replace
75-GND
2K
min.
76-GND
2K
min.
Replace.
77-GND
12K
min.
If
not,
clear
terminal
strip
If
resistance
is
OK,
and
leads,
and
also
check
possible
defective
If
not,
examine
amphenol
SW2
and
R1
for
dirt.
PC
board.
assembly
for
faults.
If
fault
found,
repair
or
If
amphenol
OK,
possible
replace
amphenol
assembly
.
defective
PC
board.