07/02/1
1 M40CT_GB
PROBLEM
AS
SO
CI
AT
ED
SY
MP
TO
MS
POSSIBLE CAUSE
VERIFICA
TIONS
WHA
T T
O DO
P1
1
Lack
of
wel
-
ding
current
control
Full
welding
power
(without
current
control)
regardless
of
the
knob
positio
n.
When
the
auto-idle
is
installed,
the
machine
remains
at
low
r.p.m.
Hall sensor failed
In
order
to
check
the
proper
operation
of
the
Hall
sensor
it is
necessary
to
use
specific
test
and
troubleshooting
tools.
Anyway
, a
visual
inspection
coul
be
enough
to
localise
possible
damages,
with
particular
reference
to
possible
wear
of
the
cable
end
coming
out
of
the
Hall
sensor
potting.
Please
check
also
the
connector
contacts
crimping
at
the
opposite end of the cable. In case of evidence of damages consider the suggested action
Replace the Hall sensor
P12
Lack
of
wel
-
ding
current
control
(ap
-
plicable
only
to CS 350)
Full
welding
power
(without
current
control)
regardless
of the knob position
Chopper
and/or
driver
board failed
Disconnect
the
chopper
cable
from
the
connector
J3
of
the
W
AC.
Check
that
the
open
circuit
voltage
is
<
1V
. If
not
put
a
light
resistive
load
at
the
welding
output
(few
kohms
are
enough)
and
check
again
the
previous
condition.
If
it is
not
satisfied
the
chopper
is
faulty
.
If
a
welding
load
bank
and
a
clamp
DC
amp
meter
are
available,
another
test
can
be
done
to
localise
the
failed
section/s.
To
this
purpose
set
the
load
bank
for
a
current
of
a few
tens
of
amps
and
measure
the
current
at
the
output
of
each
chopper
section
(the
group
of
cables
which
connect
the
chopper
to
one
end
of
the
welding
current
leveling
reactor).
The
sections
through
which
the
current
flows
are
failed
or
improperly
driven
by
the
driver
board.
If
the
test
confirms
this
type
of
failure
consider
the
suggested
cor
-
rective action.
Replace
the
chopper
and
the
driver board
P13
Lack
of
wel
-
ding
current
control
(ap
-
plicable
only
to CS 230)
Full
welding
power
(without
current
control)
regardless
of the knob position
Chopper faulty
Disconnect
the
chopper
cable
from
the
connector
J3
of
the
W
AC.
Check
that
the
open
circuit
voltage
is
<
1V
. If
not
put
a
light
resistive
load
at
the
welding
output
(few
kohms
are
enough)
and
check
again
the
previous
condition.
If
it is
not
satisfied
the
chopper
is
faulty
.
In this case consider the suggested corrective action.
Replace the chopper
P14
Knob
irregu
-
lar
or
mis
-
sing
current
adjustment
When
turning
the
knob
the
current
setting
(and
the
vol
-
tage
setting,
if
applicable)
do
not
change
or
change
irregularly
The
potentiometer
which
regulates
the
welding
current
(and
the
welding
voltage,
when
applica
-
ble) is faulty
Check
if the
regulation
through
remote
control
works
properly
. If
confirmed,
consider
the
suggested corrective action.
Replace the potentiometer
CS
M
40.3
REV.0-02/11
Trouble shooting
