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Miller MW100, KC256506 Owner's manual

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June
1992
Form:
OM-154
405
Effective
With
Seria
No.
KC256506
MW100
OWNERS
MANUAL
~
IMPORTANT:
Read
and
understand
the
entire
contents
of
this
manual,
with
special
emphasis
on
the
safety
material
throughout
the
manual,
before
installing,
operating,
or
maintaining
this
equipment.
This
unit
and
these
instructions
are
for
use
only
by
persons
trained
and
experienced
in
the
safe
operation
of
welding
equipment.
Do
not
allow
untrained
persons
to
install,
operate,
or
maintain
this
unit.
Contact
your
distributor
if
you
do
not
fully
understand
these
instructions.
tbois
coven
5/92
ST.155
502
PRINTED
IN
USA
The
following
safety
alert
symbol
and
signal
words
are
used
throughout
this
manual
to
call
attention
to
and
identify
different
levels
of
hazard
and
special
instructions.
a
WARNING
WARNING
statements
identify
procedures
or
practices
which
must
be
followed
to
avoid
serious
personal
injury
or
loss
of
life.
a
CAUTION
CAUTION
statements
identify
procedures
or
practices
which
must
be
followed
to
avoid
minor
personal
injury
or
damage
to
this
equipment.
~
IMPORTANT:
statements
identify
special
instructions
necessary
for
the
most
efficient
operation
of
this
equipment.
ARC
WELDING
SAFETY
PRECAUTIONS
ELECTRIC
SHOCK
can
kill.
Touching
live
electrical
parts
can
cause
fatal
shocks
or
severe
burns.
The
electrode
and
work
circuit
is
electrically
live
whenever
the
output
is
on.
The
input
power
circuit
and
machine
internal
circuits
are
also
live
when
power
is
on.
In
semiautomatic
or
automatic
wire
welding,
the
wire,
wire
reel,
drive
roll
housing,
and
all
metal
parts
touching
the
welding
wire
are
electrically
live.
Incorrectly
installed
or
improperly
grounded
equipment
is
a
hazard.
1.
Do
not
touch
live
electrical
parts.
2.
Wear
dry,
hole-free
insulating
gloves
and
body
protection.
3.
Insulate
yourself
from
work
and
ground
using
dry
insulating
mats
or
covers.
4.
Disconnect
input
power
or
stop
engine
before
installing
or
servicing
this
equipment.
5.
Properly
install
and
ground
this
equipment
according
to
its
Owners
Manual and
national,
state,
and
local
codes.
Turn
oft
all
equipment
when
not
in
use.
Do
not
use
worn,
damaged,
undersized,
or
poorly
spliced
cables.
Do
not
wrap
cables
around
your
body.
Ground
the
workpiece
to
a
good
electrical
(earth)
ground.
Do
not
touch
electrode
while
in
contact
with
the
work
(ground)
circuit.
11.
Use
only
well-maintained
equipment.
Repair
or
replace
damaged
parts
at
once.
12.
Wear
a
safety
harness
to
prevent
falling
if
working
above
floor
level.
13.
Keep
all
panels
and
covers
securely
in
place.
A~
WARNING
ARC
WELDING
can
be
hazardous.
PROTECT
YOURSELF
AND
OTHERS
FROM
POSSIBLE
SERIOUS
INJURY
OR
DEATH.
KEEP
CHILDREN
AWAY.
PACEMAKER
WEARERS
KEEP
AWAY
UNTIL
CONSULTING
YOUR
DOCTOR.
In
welding,
as
in
most
jobs,
exposure
to
certain
hazards
occurs.
Welding
is
safe
when
precautions
are
taken.
The
safety
information
given
below
is
only
a
summary
of
the
more
complete
safety
information
that
will
be
found
in
the
Safety
Standards
listed
on
the
next
page.
Read
and
follow
all
Safety
Standards.
HAVE
ALL
INSTALLATION,
OPERATION,
MAINTENANCE,
AND
REPAIR
WORK
PERFORMED
ONLY
BY
QUALIFIED
PEOPLE.
6.
7.
8.
9.
10.
ARC
RAYS
can
burn
eyes
and
skin;
NOISE
can
damage
hearing.
Arc
rays
from
the
welding
process
produce
intense
heat
and
strong
ultraviolet
rays
that
can
burn
eyes
and
skin.
Noise
from
some
processes
can
damage
hearing.
1.
2.
3.
4.
5.
Wear
a
welding
helmet
fitted
with
a
proper
shade
of
filter
(see
ANSI
Z49.1
listed
in
Safety
Standards)
to
protect
your
face
and
eyes
when
welding
or
watching.
Wear
approved
safety
glasses.
Side
shields
recommended.
Use
protective
screens
or
barriers
to
protect
others
from
flash
and
glare;
warn
others
not
to
watch
the
arc.
Wear
protective
clothing
made
from
durable,
flame-resistant
material
(wool
and
leather)
and
foot
protection.
Use
approved
ear
plugs
or
ear
muffs
if
noise
level
is
high.
FUMES
AND
GASES
can
be
hazardous
5.
Work
in
a
confined
space
only
if
it
is
well
ventilated,
or
while
to
your
health.
wearing
an
air-supplied
respirator.
Shielding
gases
used
for
Weldingproducesfumesandgases.
Breathingthese
fumes
and
gases
can
be
hazardous
to
your
health.
welding
can
displace
air
causing
injury
or
death.
Be
sure
the
breathing
air
is
safe.
1.
2.
Keep
your
head
out
of
the
fumes.
Do
not
breath
the
fumes.
.
If
inside,
ventilate
the
area
and/or
use
exhaust
at
the
arc
to
6.
Do
not
weld
in
locations
near
degreasing,
cleaning,
or
spraying
operations.Theheatandraysofthearccanreactwithvaporsto
form
highly
toxic
and
irritating
gases.
remove
welding
fumes
and
gases.
7.
Do
not
weld
on
coated
metals,
such
as
galvanized,
lead,
or
3.
If
ventilation
is
poor,
use
an
approved
air-supplied
respirator.
cadmium
plated
steel,
unless
the
coating
is
removed
from
the
4.
Read
the
Material
Safety
Data
Sheets
(MSDSs)
and
the
weld
area,
the
area
is
well
ventilated,
and
if
necessary,
while
manufacturers
instruction
for
metals,
consumables,
coatings,
wearing
an
air-supplied
respirator.
The
coatings
and
any
metals
and
cleaners,
containing
these
elements
can
give
off
toxic
fumes
if
welded.
ERRATA
SHEET
CHANGES
TO
SECTION
1
SPECIFICATIONS
September
7,
1993
FORM:
OM-154
405
Use
above
FORM
number
when
ordering
extra
manuals.
Replace
Figure
1-1.
Volt-Ampere
Curve
And
Duty
Cycle
Chart
Figure
1-1.
Volt-Ampere
Curve
And
Duty
Cycle
Chart
CHANGES
TO
SECTION
2-INSTALLATION
Replace
Section
2-6.
Threading
And
Feeding
Welding
Wire
(see
Page
2
on
this
Errata
Sheet)
CHANGES
TO
SECTION
6
PARTS
LIST
Change
Parts
List
as
follows:
12-
120964
12-
120077
12-
Added
113
494
Deleted
135
615
~First
digit
represents
page
no
digits
following
dash
represent
item
no.
BE
SURE
TO
PROVIDE
MODEL
AND
SERIAL
NUMBER
WHEN
ORDERING
REPLACEMENT
PARTS.
After
this
manual
was
printed,
refinements
in
equipment
design
occurred.
This
sheet
lists
exceptions
to
data
appearing
later
in
this
manual.
0
20
30
25
~20
-J
~15
0
o
10
5
0
150
I
25
00
75
a
x
~
50
-J
37.5
25
0
40
60
80
100
DC
AMPERES
120
The
volt-ampere
curves
show
the
minimum
and
maximum
voltage
and
amperage
output
capabilities
of
the
welding
power
source.
Curves
of
other
settings
fall
be
tween
the
curves
shown.
Duty
cycle
is
how
long
the
unit
can
operate
withina
ten
minute
period
without
causing
overheating
or
damage.
This
unit
is
rated
at
20%
duty
cycle
allowing
welding
2
minutes
out
of
every
10
minutes.
This
gun
is
rated
at
60%
duty
cycle
when
using
CO2
shielding
gas
and
30%
when
using
mixed
shielding
gas.
ssbl.1
10/91
ST155869/sbl.310/91
SB-121
475
10
IS
20
25
30 40
50 60
70
60
90
00
DUTY
CYCL~
%
Part
Replaced
--
No.
With
Description
Cord
Set
Bushing,
nylon
.390
ID
x
.750
OD
x
.750
Ig
2-6.
Threading
And
Feeding
Welding
Wire
a
WARNING
CYLINDERS
can
explode
if
damaged.
Keep
cylinders
away
from
welding
and
other
electrical
circuits.
Never
touch
cylinder
with
welding
electrode.
Always
secure
cylinder
to
running
gear,
wall,
or
other
stationary
support.
ELECTRIC
SHOCK
can
kill.
Do
not
touch
live
electrical
parts.
The
welding
wire,
drive
rolls,
drive
assembly,
and
all
metal
parts
touching
the
welding
wire
are
electrically
live
when
welding
or
feeding
wire
using
gun
trigger.
WELDING
WIRE
can
cause
puncture
wounds.
Do
not
press
gun
trigger
until
instructed
to
do
so.
Do
not
point
gun
toward
any
part
of
the
body,
other
people,
or
any
metal
when
threading
welding
wire.
HOT
SURFACES
can
burn
skin.
Allow
gun
to
cool
before
touching.
swarn5
1
10/91
/
swarn2.1
9/91
1
Wire
Spool
2
Hub
Tension Nut
Remove
and
retain
Tools
Needed:
~
9/16
in
Install
1
lb
spool
Grasp
spool
in
one
hand
and
turn
while
using
a
wrench
to
adjust
nut.
When
a
slight
force
is
needed
to
turn
spool,
tension
is
set.
Loosen
wire
from
spool,
cut
oft
bent
wire,
and
pull
6
in.
(150
mm)
of
wire
from
spool.
3
Pressure
Adjustment
Open
pressure
assembly.
4
Wire
Inlet
Guide
5
Drive
Roll
6
Wire
Outlet
Guide
Thread
wire
through
inlet
guide,
along
drive
roll
groove,
and
into
out
let
guide.
Close
pressure
assembly.
Lay
gun
cable
out
straight.
7
Nozzle
8
Contact
Tube
Remove
nozzle
and
contact
tube.
9
Gun
Trigger
Turn
ON
unit,
press
gun
trigger,
and
feed
2
in.
(55
mm)
of
wire
out
of
gun.
Turn
OFF
unit
and
reinstall
contact
tube
and
nozzle.
10
Adjusting
Pressure
Turn
ON
unit
and
check
drive
roll
pressure
by
feeding
wire
against
a
wood
board
or
concrete
surface;
wire
should
feed
steadily
without
slipping.
Tighten
pressure
adjustment
if
necessary.
Figure
2-5.
Feeding
Welding
Wire
TO
USE
I
LB SPOOL:
2
3
9
Close
door.
7
8
ST.800
316
/
Ret
ST.
155
505
/
Ret
ST.
155
504
/
S.0627.A
OM-154
405
Page
2
FLYING
SPARKS
AND
HOT
METAL
can
cause
injury.
Chipping
and
grinding
cause
flying
metal.
As
welds
cool,
they
can
throw
off
slag.
CYLINDERS
can
explode
if
damaged;
Shielding
gas
cylinders
contain
gas
under
high
pressure.
If
damaged,
a
cylinder
can
explode.
Since
gas
cylinders
are
normally
part
of
the
welding
process,
be
sure
to
treat
them
carefully.
1.
Protect
compressed
gas
cylinders
from
excessive
heat,
mechanical
shocks,
and
arcs.
2.
Install
and
secure
cylinders
in
an
upright
position
by
chaining
them
to
a
stationary
support
or
equipment
cylinder
rack
to
prevent
falling
or
tipping.
1.
Wear
approved
face
shield
or
safety
goggles.
Side
shields
recommended.
2.
Wear
proper
body
protection
to
protect
skin.
3.
Keep
cylinders
away
from
any
welding
or
other
electrical
circuits.
4.
Never
allow
a
welding
electrode
to
touch
any
cylinder.
5.
Use
only
correct
shielding
gas
cylinders,
regulators,
hoses,
and
fittings
designed
for
the
specific
application;
maintain
them
and
associated
parts
in
good
condition.
6.
Turn
face
away
from
valve
outlet
when
opening
cylinder
valve.
7.
Keep
protective
cap
in
place
over
valve
except
when
cylinder
is
in
use
or
connected
for
use.
8.
Read
and
follow
instructions
on
compressed
gas
cylinders.
associated
equipment,
and
CGA
publication
P-i
listed
in
Safety
Standards.
PRINCIPAL
SAFETY
STANDARDS
Safety
in
Welding
and
Cutting,
ANSI
Standard
Z49.1,
from
American
Welding
Society,
550
N.W.
LeJeune
Rd,
Miami
FL
33126
Safetyand
Health
Standards,
OSHA
29
CFR
1910,
from
Superintendent
of
Documents,
U.S.
Government
Printing
Office,
Washington,
D.C.
20402.
Recommended
Safe
Practices
for
the
Preparation
for
Welding
and
Cutting
of
Containers
That
Have
Held
Hazardous
Substances,
American
Welding
Society
Standard
AWS
F4.
1,
from
American
Welding
Society,
550
N.W.
LeJeune
Rd,
Miami,
FL
33126
National
Electrical
Code,
NFPA
Standard
70,
from
National
Fire
Protection
Association,
Batterymarch
Park,
Quincy,
MA
02269.
Safe
Handling
of
Compressed
Gases
in
Cylinders,
CGA
Pamphlet
P-I,
from
Compressed
Gas
Association,
1235
Jefferson
Davis
Highway,
Suite
501,
Arlington,
VA
22202.
Code
for
Safety
in
Welding
and
Cutting,
CSA
Standard
Wi
17.2,
from
Canadian
Standards
Association,
Standards
Sales,
178
Rexdaie
Boulevard,
Rexdale,
Ontario,
Canada
M9W
1
R3.
Safe
Practices
For
Occupation
And
Educational
Eye
And
Face
Protection,
ANSI
Standard
Z87.
1,
from
American
National
Standards
Institute,
1430
Broadway,
New
York,
NY
10018.
Cutting
And
Welding
Processes,
NFPA
Standard
51
B,
from
National
Fire
Protection
Association,
Batterymarch
Park,
Quincy,
MA
02269.
TABLE
OF
CONTENTS
SECTION
1
SPECIFICATIONS
i-i.
Volt-Ampere
Curve
And
Duty
Cycle
Chart
SECTION
2
INSTALLATION
2-i.
Installing
Work
Clamp
2
2-2.
Installing
Gas
Supply
2
2-3.
Connecting
Input
Power
2
2-4.
Gun
Polarity
For
Wire
Type
3
2-5.
Installing
Welding
Gun
3
2-6.
Threading
And
Feeding
Welding
Wire
4
SECTION
4
MAINTENANCE
&
TROUBLESHOOTING
4-i.
Overload
Protection
6
4-2.
Drive
Assembly
Maintenance
4-3.
Gun
Maintenance
4-4.
Troubleshooting
7
8
8
SECTION
5
ELECTRICAL
DIAGRAMS
9
SECTION
6
PARTS
LIST
Figure
6-1.
Main
Assembly
Figure
6-2.
MWG-i
60M
Gun
11
12
WELDING
can
cause
fire
or
explosion.
Sparks
and
spatter
fly
off
from
the
welding
arc.
The
flying
sparks
and
hot
metal,
weld
spatter,
hot
workpiece,
and
hot
equipment
can
cause
fires
and
burns.
Accidental
contact
of
electrode
orwelding
wire
to
metal
objects
can
cause
sparks,
overheating,
or
fire.
5.
Watch
for
fire,
and
keep
a
fire
extinguisher
nearby.
7.
8.
6.
Be
aware
that
welding
on
a
ceiling,
floor,
bulkhead,
or
partition
can
cause
fire
on
the
hidden
side.
1.
Protect
yourself
and
others
from
flying
sparks
and
hot
metal.
2.
Do
not
weld
where
flying
sparks
can
strike
flammable
material.
3.
Remove
alt
flammables
within
35
ft
(10.7
m)
of
the
welding
arc.
If
this
is
not
possible,
tightly
cover
them
with
approved
covers.
4.
Be
alert
that
welding
sparks
and
hot
materials
from
welding
can
easily
go
through
small
cracks
and
openings
to
adjacent
areas.
Do
not
weld
on
closed
containers
such
as
tanks
or
drums.
Connect
work
cable
to
the
work
as
close
to
the
welding
area
as
practical
to
prevent
welding
current
from
traveling
long,
possibly
unknown
paths
and
causing
electric
shock
and
fire
hazards.
9.
Do
not
use
welder
to
thaw
frozen
pipes.
10.
Remove
stick
electrode
from
holder
or
cut
off
welding
wire
at
contact
tip
when
not
in
use.
Ii.
Wear
oil-free
protective
garments
such
as
leather
gloves,
heavy
shirt,
cuffless
trousers,
high
shoes,
and
a
cap.
SECTION
3OPERATION
5
SECTION
1
SPECIFICATIONS
Table
1-1.
Welding
Power
Source
Rated
Output
(Air
Cooled)
Cable
Length
160
Amperes
At
60%
Duty
Cycle
Using
CO2
Shielding
Gas
10
ft.
(3
m)
1-1.
Volt-Ampere
Curve
And
Duty
Cycle
Chart
a
CAUTION
wfwam8.1
10/91
i
~
d
~
S
The
volt-ampere
curves
show
the
minimum
and
maximum
voltage
and
amperage
output
capabilities
of
the
welding
power
source.
Curves
of
other
settings
fall
be
tween
the
curves
shown.
Duty
cycle
is
how
long
the
unit
can
operate
within
a
ten
minute
period
without
causing
overheating
or
damage.
This
unit
is
rated
at
20%
duty
cycle
allowing
welding
2
minutes
out
of
every
10
minutes.
This
gun
is
rated
at
60%
duty
cycle
~N
~Z
.~
~;
~
RM~E
S
~,R
S~~
~
M~
63
~S
~
~__,
0
20 .0 60
so
oo so
.o
D.C.
~
ISO
25
100
-
-..
when
using
CO2
shielding
gas
and
30%
when
using
mixed
shielding
gas.
-.
-
-
-
-
-
-.-
-
-
-
75
~,-.~-
---
~
~-.
~
SO
s
37.5
- -
-
25
-
---
0

...
0
IS
20
25
30
.0
50
o.rry
c,o.E
S
--
-
.
~
-
--
-
.
-
60
70
60
9000
SSb1.1
10191
SB-121
090/
sDl
.310/91
5B-121
475
Specification
Description
Type
Of
Output
Rated
Weld
Output
Type
Of
Input
Power
Input
Amperes
At
Rated
Output
KVAJKW
Used
At
Rated
Output
Max.
Open-Circuit
Voltage
Control
Circuit
Voltage
At
Gun
Welding
Processes
Speed
Range
At
No
Load
Wire
Diameter
Range
Overall
Dimensions
Weight
Direct
Current/Constant
Voltage
(DCICV)
70
Amperes,
16
Volts
DC,
20%
Duty
Cycle
Single-Phase;
60
Hz;
At
115
Volts
AC
I
5A
At
11
5V
2.2
kVA/2
kW
29
Volts
DC
24
Volts
DC
Gas
Metal
Arc
(GMAW)
And
Flux
Cored
Arc
Welding
(FCAW)
22
To
286
ipm
(0.6
To
7.3
mpm)
.023
And
.030
in.
(0.6
And
0.8
mm)
Length:
16-1/2
in.
(419
mm);
Width:
9-1/2
in.
(241
mm);
Height:
17
in.
(432
mm)
Net:
53
lbs.
(24
kg);
Ship:
62
lbs.
(28
kg)
Welding
Gun
USING
GUN
BEYOND
DUTY
CYCLE
RATING
can
damage
gun.
Do
not
use
gun
beyond
rated
amperage
when
using
CO2
shielding
gas.
Use
gun
at
30%
duty
cycle
when
using
mixed
shielding
gas.
Figure
1-1.
Volt-Ampere
Curve
And
Duty
Cycle
Chart
OM-154
405
Page
1
2-1.
Installing
Work
Clamp
SECTION
2INSTALLATION
Insert
screw
through
terminal
on
work
cable.
Thread
screw
through
jaw
and
clamp.
5
Flange
Nut
2-2.
Installing
Gas
Supply
a
WARNING
C
S
YLINDERS
can
explode
if
damaged.
Keep
cylinders
away
from
welding
and
other
electrical
circuits.
Never
touch
cylinder
with
welding
electrode.
Always
secure
cylinder
to
running
gear,
wall,
or
other
stationary
support.
~
BUILDUP
OF
SHIELDING
GAS
can
harm
health
or
kill.
Shut
off
shielding
gas
supply
when
not
in
use.
warn4.1
9/91
6
D~
U
U
U
1
2
3
Obtain
gas
cylinder
and
chain
to
running
gear,
wall,
or
other
station
ary
support.
1
Cap
2
Cylinder
Valve
Remove
cap,
stand
to
side
of
valve,
and
open
valve
slightly.
Gas
flowblowsdustanddirtfromvalve.
Close
valve.
3
Cylinder
(CO2
Shown)
4
CO2
0-Ring
5
Regulator
Install
onto
gas
cylinder
so
that
face
is
vertical.
Tools
Needed:
7
6
Flowmeter
Flow
rate
is
set
to
20
cfh
(cubic
feet
per
hour).
7
Gas
Hose
Connection
1-1/Bin.,
5/8
in.
Install
gas
hose
between
flow-
meter
and
welding
power
source.
ssb3.1
2/92
ST-154
583/
ST-154
623
Figure
2-2.
Typical
CO2
Regulator/Flowmeter
Installation
2-3.
Connecting
Input
Power
Connect
unit
to
a
properly
grounded
receptacle
of
al
5
or
20
ampere
individual
branch
circuit
protected
by
time-delay
fuses
or
circuit
breakers.
Select
an
extension
cord
of
14
AWG
for
up
to
60
ft.
(19
m)
or
12
AWG
for
up
to
75
ft.
(23
m).
1
Work
Cable
2
Work
Clamp
Tools
Needed:
3
1/4-20
x
1/2
in.
Self-Thread
ing
Screw
______~
3/8
in.,
~
7/16
in.
4
Clamp
Jaw
Figure
2-1.
Installing
Work
Clamp
Secure
screw
with
nut.
OM-154
405
Page
2
2-6.
Threading
And
Feeding
Welding
Wire
a
WARNING
CYLINDERS
can
explode
if
damaged.
Keep
cylinders
away
from
welding
and
other
electrical
circuits.
Never
touch
cylinder
with
welding
electrode.
Always
secure
cylinder
to
running
gear,
wall,
or
other
stationary
support.
ELECTRIC
SHOCK
can
kill.
Do
not
touch
live
electrical
parts.
The
welding
wire,
drive
rolls,
drive
assembly,
and
all
metal
parts
touching
the
welding
wire
are
electrically
live
when
welding
or
feeding
wire
using
gun
trigger.
WELDING
WIRE
can
cause
puncture
wounds.
Do
not
press
gun
trigger
until
instructed
to
do
so.
Do
not
point
gun
toward
any
part
of
the
body,
other
people,
or
any
metal
when
threading
welding
wire.
HOT
SURFACES
can
burn
skin.
Allow
gun
to
cool
before
touching.
Swarn5.1
10/91
/
Swarn2.1
9/91
1
Wire
Spool
Tools
Needed:
~
9/16
in.
Figure
2-5.
Feeding
Welding
Wire
2
Hub
Tension
Nut
Grasp
spool
in
one
hand
and
turn
while
using
a
wrench
to
adjust
nut.
When
a
slight
force
is
needed
to
turn
spool,
tension
is
set.
Loosen
wire
from
spool
and
cut
off
bent
wire
and
pull
6
in.
(150
mm)
of
wire
from
spool.
3
Pressure
Adjustment
Open
pressure
assembly
4
Wire
Inlet
Guide
5
Drive
Roll
6
Wire
Outlet
Guide
Thread
wire
through
inlet
guide,
along
drive
roll
groove,
and
into
Out
let
guide.
Close
pressure
assembly.
Lay
gun
cable
out
straight.
7
Nozzle
8
Contact
Tube
Remove
nozzle
and
contact
tube.
9
Gun
Trigger
Turn
ON
unit,
press
gun
trigger,
and
feed
2
in.
(55
mm)
of
wire
out
of
gun.
Turn
OFF
unit
and
reinstall
contact
tube
and
nozzle.
10
Adjusting
Pressure
Turn
ON
unit
and
check
drive
roll
pressure
by
feeding
wire
against
a
wood
board
or
concrete
surface;
wire
should
feed
steadily
without
7
slipping.
Tighten
pressure
adjustment
if
nec
essary.
Close
door.
Ret.
ST.
155
505
/
Ref
ST.155
~fl4
/
S.0R27.A
OM-154
405
Page
4
SECTION
3
OPERATION
2
Wire
Speed
Control
Use
control
to
select
a
wire
feed
speed.
The
numbers
around
the
control
are
not
a
wire
feed
speed
(see
rear
cover).
3
Weld
Selector
Switches
Switches
are
used
to
select
an
arc
voltage
(see
rear
cover).
4
Work
Clamp
Use
wire
brush
or
sandpaper
to
clean
metal
at
weld
(oint
area.
Connect
work
clamp
to
clean,
paint-free
location
on
workpiece,
as
close
as
possible
to
weld
area.
~t
~
READ
SAFETY
BLOCKS
at
beginning
of
manual
before
proceeding.
M
OVING
PARTS
can
cause
injury.
ARCING
can
damage
switch.
Keep
away
from
pinch
points
such
as
drive
rolls.
Do
not
change
VOLTAGE
switch
position
while
Keep
all
doors,
panels,
covers,
and
guards
closed
welding.
and
securely
in
place.
.
Arcing
inside
switch
can
damage
contacts,
causing
switch
to
fail.
1
2
/
~s8
3
1
Insulating
Gloves
2
Safety
Glasses
With
Side
Shields
3
Welding
Helmet
Wear
dry
insulating
gloves,
safety
glasses
with
side
shields,
and
a
welding
helmet
with
a
correct
shade
of
filter
(see
ANSI
Z49.1).
sb3.1
10/91
Figure
3
-1.
Safety
Equipment
1
Power
Switch
Use
switch
to
turn
unit
ON
and
OFF.
Tools
Needed:
4
Figure
3-2.
Controls
Ref.
ST-155
503/
SC-153
020
OM-154
405
Page
5
SECTION
4
MAINTENANCE
&
TROUBLESHOOTING
a
WARNING
ELECTRIC
SHOCK
can
kill.
Do
riot
touch
live
electrical
parts.
Turn
OFF
welding
power
source,
and
disconnect
input
power
before
inspecting,
maintaining,
or
servicing.
HOT
PARTS
can
cause
severe
burns.
Allow
cooling
period
before
maintaining
or
servicing.
~
4
M
OVING
PARTS
can
cause
injury.
Keep
away
from
moving
parts.
Keep
away
from
pinch
points
such
as
drive
rolls.
m
.
Maintenance
and
troubleshooting
to
be
performed
only
by
qualified
persons.
swari,8
2~
ia/sr
Table
4-1.
Maintenance
Schedule
Time
Maintenance
Before
each
use.
Tighten
all
connections.
Check
gun
and
clean
nozzle.
After
each
spool
of
wire.
Blow
out
gun
liner.
Clean
and
check
wire
drive
parts;
replace
as
necessary.
Every
3
months.
Tape
or
replace
cracked
cables:
clean
and
tighten
connections.
Replace
unreadable
labels.
Every
6
months.
Blow
out
or
vacuum
inside
of
unit.
4-1.
Overload
Protection
READ
SAFETY
BLOCKS
at
start
of
Section
4
before
proceeding.
Thermostat
TP1
protects
the
unitfrom
damage
due
to
overheating.
If
main
transformer
TI
gets
too
hot,
TP1
opens
and
weld
output
stops.
The
fan
keeps
running
to
cool
the
transformer.
Wait
several
minutes
before
trying
to
weld.
A.
Overheating
B.
Motor
Fuse
Fl
Turn
OFF
and
unplug
unit.
Unlatch
door,
remove
handle,
and
remove
door/wrapper.
1
Fuse
Fl
(See
Parts
List
For
Rating)
If
this
fuse
opens,
the
wire
drive
motor
does
not
run.
Check
and
replace
fuse
if
neces
sary.
Twist
fuse
holder
clockwise
to
secure.
Reinstall
wrapper
and
handle,
and
latch
door.
ST-155
723
/
ST-r52
031
Tools
Needed:
~:~===z~
~:
~r
3/8
in.
Figure
4-1.
Fuse
Fl
Location
OM-154
405
Page
6
4-2.
Drive
Assembly
Maintenance
~}i~~J
~-jjjjlIrm~
READ
SAFETY
BLOCKS
at
start
of
7
1_1r
~
Section
4
before
proceeding.
Turn
OFF
and
unplug
unit.
1
Wire
Spool
2
Gun
Contact
Tube
Cut
welding
wire
off
at
contact
tube.
Retract
wire
onto
spool
and
secure.
3
Pressure
Roll
Arm
4
Cotter
Pin
5
Pin
6
Screw
7
Bearing
Remove
bearing
as
shown.
Install
new
bearing
and
secure
with
screw.
Reinstall
arm
onto
pin
and
secure
2
with
cotter
pin.
8
Setscrew
9
Smooth
Groove
For
Hard
Wire
10
Drive
Roll
Remove
drive
roll
as
shown.
Use
a
wire
brush
to
clean
drive
roll.
Push
drive
roll
onto
shaft
with
de
sired
groove
in.
Turn
drive
roll
so
one
setscrew
faces
flat
side
of
shaft,
and
tighten
both
setscrews.
11
Knurled
Groove
For
Flux-
Cored
Wire
12
WirelnletGuide
Remove
guide
by
pressing
on
barbed
area
or
cutting
off
one
end
near
housing
and
pulling
it
out
of
hole.
Push
new
guide
into
hole
from
rear
until
it
snaps
in
place.
Thread
welding
wire
(see
Section
2-6).
Close
door.
Tools
Needed:
~
5/6~1
ST-155504/ST-154
199
Figure
4-2.
Drive
Assembly
Maintenance
OM-154
405
Page
7
4-3.
Gun
Maintenance
____
READ
SAFETY
BLOCKS
at
start
of
Section
4
before
proceeding.
I
FLYING
METAL
CHIPS
AND
DIRT
can
cause
injury
and
damage
equipment.
Point
gun
away
from
people
and
in
a
safe
direction
when
blowing
out
with
compressed
air.
swarniOl
10/91
Turn
OFF
and
unplug
unit.
I
Wire
Spool
Cut
welding
wire
off
at
contact
tube.
Retract
wire
onto
spool
and
Se-
2
Gun
Securing
Nut
Disconnect
trigger
leads.
Loosen
nut
and
remove
gun
and
trigger
leads.
3
Nozzle
4
Contact
Tube
5
Head
Tube
4
6
Liner
Collet
Disassemble
gun
as
shown.
5
7
Liner
Pull
liner
from
this
end.
Blow
gun
casing
out
with
compressed
air.
Insert
new
liner
into
gun
casing
6
until
even
with
end
of
head
tube.
Install
collet
onto
liner.
~
~
Insert
gun
into
feeder
and
mark
Install
contact
tube
and
nozzle.
where
liner
touches
drive
roIl.
Re
move
gun
and
cut
liner
off.
Rein
~
stall
gun
so
that
liner
is
as
close
as
possible
to
drive
rolls
without
touching.
Thread
welding
wire
(see
Section
2-6).
Close
door.
R~t
ST-155
506
/
R~f
ST.lcS
~
Figure
4-3.
Gun
Maintenance
4-4.
Troubleshooting
____
READ
SAFETY
BLOCKS
at
start
of
Section
4
before
proceeding.
Remedy
-~
-~
-~
-~
Section
2-3
4-1
B
2-5
]
-~
Secure
power
cord
plug
in
receptacle.
Motor
fuse
Fl
open,
replace
Fl.
Replace
building
line
fuse
or
reset
circuit
breaker
if
open.
Secure
gun
trigger
leads
or
repair
leads,
or
replace
trigger
switch.
Tools
Needed:
3/8
in.
5/16
in.
1
2
3
cure.
Welding
Trouble
No
weld
output;
wire
does
not
feed.
No
weld
output;
wire
feeds.
No
weld
output;
wire
does
not
feed;
fan
-~
Thermostat
TP1
open
(overheating).
Allow
fan
to
run;thethermo-
-~
4-lA
motor
continues
to
run,
stat
will
close
when
the
unit
has
cooled.
I
Low
weld
output.
--~
Connect
work
clamp
to
get
good
metal
to
metal
contact.
~Replace
contact
tube.
1
-.~I
Connect
unit
to
proper
input
voltage
or
check
for
low
line
voltage.
-..~
2-3
Figure
3-2
j
4-3
OM-154
405
Page
8
SECTION
5
ELECTRICAL
DIAGRAMS
Figure
5-1.
Circuit
Diagram
For
Welding
Power
Source
SA-1
53694-A
Straighten
gun
cable
and/or
replace
damaged
parts.
Adjust
drive
roll
pressure.
Readjust
hub
tension.
Replace
contact
tube
if
blocked.
Wire
Drive/Gun
Trouble
________________________________________________
Electrode
wire
feeding
stops
during
 
-~
-~
4-3
welding.
________________________________________________________
____________
2-6
2-6
-~
4-3
-a
4-2,4-3
-a
4-2
-~
2-5
-~
4-lB
______________________________________________
4-2,
4-3
---
--
Clean
or
replace
wire
inlet
guide
or
liner
if
dirty
or
plugged.
Replace
drive
roll
or
pressure
bearing
if
worn
or
slipping.
Secure
gun
trigger
leads
or
repair
leads,
or
replace
trigger
switch.
Check
and
replace
Fl.
Check
and
clear
any
restrictions
at
drive
assembly
and
liner
Have
nearest
Factory
Authorized
Service
Station
check
drive
motor.
2
//
CR1
I
L.
PLG
I
Dl
CR/V.
TORCH
OM-154
405
Page
9
SI
S2
S3
rDSo.1
TPIGDSP
LEADS
0
En
0
En
-o
C)
Co
CD
0
SPLICE
P2
GND
POWER
CORD
SC-154
134-A
Figure
5-2.
Wiring
Diagram
For
Welding
Power
Source
SECTION
6
PARTS
LIST
E
U,
C
CD
C,
U,
U,
U,
p
C~)
c,J
(0
c,J
(0
c~J
0)
0
(4
U,
C,,
/
/
/
/
/
0)
r
U,.
(4
0)
U-
OM-154
405
Page
11
Parts
For
Main
Assembly
NOTE:
All
items
indented
by
a
dot(s)
are
included
with
the item
listed
directly
above.
Item
Part
No.
No.
Description
126
838
Drive
Assembly
1
090 416
Hinge
Pin
2
124817
DriveHousing
3
151
828
~CotterHairPin
4
112031
~Pressure
Lever
5
090
443
Bearing
111
622
Spacer
6
092 237
Knob
7
090415
Spring
8
085244
CuppedWasher
9
085
242
Fastener
10
010
224
Spring
Pin
11
058 549
Wire
Guide
12
149332
HoseClamp
13
134834
Hose
14
154
827
Drive
Roll
15
602169
Set
Screw
16
129
893
Insulator
17
119021
DriveMotor
18
153727
Baffle
19
111
929
Hub
20
010910
Washer
21
073 355
Spring
22
010909
Nut
23
111
998
Cotter
Hair
Pin
24
120706
Relay
25
120675
Bracket
I
Item
Part
-_________________
J
No.
No.
Description
26
111
931
Fan
Motor
27
005
656
Fan
Blade
28
153729
Handle
154596
Cap,
Handle
29
+153
724
Wrapper
30 134
464
Warning
Label
31
089899
Latch
32
053
297
Fuse
Holder
33
*012
663
Fuse,
slo-blo
3A
34
119
264
Rectifier
35
010047
Tubing
36
116
619
Terminal
Assembly
038618
Link
37
Case
w/Cmpts
116996
GasValve
605
227
Nyl
Nut,
gas
valve
120964
Cord
Set
111
644
Bushing,
cord
set
119
653
Rheostat
097922
~Knob
153
698
Rocker
Switch,
SPST
153
699
Rocker
Switch
SPOT
155530
~Case
155
569
Nameplate
111
443
Bushing,
.875mtg
025 338
Bushing,
.625nitg
1
Item
Part
J
No.
No.
Description
38
153722
Side
Panel
39
120638
Thermostat,
NC
40
154
015
Transformer
153695
Coil
41
117
116
Resistor
42
087
156
Varistor
43
109039
Capacitor
44
108105
Clamp
45
118
457
Stabilizer
46
019663
Foot
47
600 325
Cable
48
153
969
Clamp
49
154
845
MWG-160M
Gun,
(Fig
6-2)
120
077
Blank,
1
.250sq
153
714
Regulator/Flowmeter
154
829
Hose
Kit
112863
.
Adapter
Fitting
113129
~PVCTubing
089
120
Hose
Clamp,
.375450
+When
ordering
a
component
originally
dis
playing
a
precautionary
label,
the
label
should
also
be
ordered.
*Recommended
Spare
Parts.
Be
sure
to
provide
Model
and
Serial
Number
when
ordering
replacement
parts.
Ret.
ST.l1O
832-0
Item
Part
No.
No.
Description
1
155
817
Handle
Assembly,
red
110795
Head
Tube
2
110780
~Nut
3
110779
~Jacket
4
110781
~Stop
5
128878
Adapter
6
154819
~Spring
7
154826
ContactTube,
.023
7
154825
ContactTube,
.030
8
154822
NozzlØ,1/2orf
8
154
821
Nozzle,
3/8
on
8
154
820
Nozzle,
flat
spot
9
110
794
Trigger
Switch
Assembly
10
080565
Terminal
11
110
792
Cable/Conduit
12
110797
Sleeve
13
154
823
LIner,
.030-.035
14
120
715
.
Collet,
.035
15
079974
0-Ring,
.500
16
110
796
Connector
17
047994
Terminal
OPTIONAL
Figure
6-2.
MWG-160M
Gun
(Fig
6-1
Item
49)
2,
.9
14
17
OM-154
405
Page
12
Suggested
Welding
Settings
Shielding
Gas
Wire
Diameter
(inch)
Operator
Control
Settings
Material
Thickness
12
ga.
and
Thicker
14-13
ga.
17-15
ga.
20-18
ga.
Thinner
Than
20
ga.
Solid
Steel
Co2
.023025
Voltage
High!
Mm
or
Max
Hi9h/
Mm
Low/
Max
Low!
Mm
.
Feed
Speed*
100
95
70
55
Solid
Steel
75%
Ar
25%
CO2
.023.
025
Voltage
-
High!
Mm
or
Max
Hi~h/
Mm
Low!
Max
Low!
Mm
Feed
Speed*
100
100
90
65
E-71T-GS
.030
Voltage
Highl
Max
High!
Mm
Low!
Max
Low!
Mm
LowI
Mm
Feed
Speed*
90
.
50
50
60
30
*Adjust
WIRE
SPEED
control
as
required.
IMPORTANT:
If
in
doubt,
set
WELD
SELECTOR
SWITCHES
for
thickness
desired
and
set
WIRE
SPEED
to
50.
The
weld
can
be
started
and
fine
tuned
during
operation.
If
input
voltage
is
low,
a
higher
WELD
SELECTOR
SWITCHES
setting
may
be
required
to
obtain
desired
weld.
OM-154
405
Page
13
/