MAC TOOLS MW165 User manual

February
1997 Form:
OM-185
356
Effective
With
Serial
No.
KH31
31 00
MW165
OWNERS MANUAIL
~
IMPORTANT: Read
and
understand
the
entire
contents
of
this
manual,
with
special
emphasis
on
the
safety
material
throughout
the
manual,
before
in
stalling,
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.
L~u_
TOOLSfi
cover
I
5/92

Ref.
ST-801
785
PRINTED
IN
USA

The
following
safety
alert
symbol
and
signal
words
are
used
throughout
this
manual
to
call
attention
to
and
identity
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.
AA
CAUTION
CAUTION
statements
identify
procedures
or
practices
which
must
be followed
to
avoid
minor
personal
injury
or
damage
to
this
equipment.
ARC
WELDING
SAFETY
PRECAUTIONS
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.
/~
-~~
-
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.
\
I
Welding
produces
fumes and
gases.
Breathing
I
these
fumes and
gases
can
be
hazardous
to
your
-.
I
health.
i-
6.
wearing
an
air-supplied respirator.
Shielding
gases
used
for
welding
can
displace
air
causing
injury
or
death.
Be
sure
the
breathing
air
is
safe.
Do
not
weld
in
locations
near
degreasing,
cleaning,
or
spraying
1.
Keep
your
head
out
of
the
fumes.
Do
not
breath
the
fumes.
2.
If
inside,
ventilate the
area
and/or
use
exhaust
at
the
arc
to
operations.
The
heat
and
rays
of
the
arc can
react
with
vapors
to
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.
ELECTRIC
SHOCK
can
kill.
Touching
live
electrical
parts
can
cause
fatal
shocks
or
severe
bums.
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
touchin9
the
welding
wire
are
electrically
live.
Incorrectly
installed
or
improperly
grounded
equipment
is
a
hazard.
5.
Properly
install and
ground
this
equipment
according
to
its
Owners
Manual and
national,
state,
and
local
codes.
6. Turn
off
all
equipment
when
not
in
use.
8.
9.
10.
7.
Do
not
use
worn,
damaged,
undersized,
or
poorly spliced
cables.
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.
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.
level.
12.
Wear
a
safety
harness
to
prevent
falling
if
working
above
floor
13.
Keep
all
panels
and
covers
securely
in
place.

WELDING
can
cause
fire
or
explosion.
Sparks
and
spatteufly
off
from
the
welding
arc.
The
flying
sparks
and
hot
metal,
weld
spatter,
hot
workpiece,
and
hot
equipment
can
cause
fires and
bums. Accidental
contact
of
electrode
or
welding
wire
to
metal
objects
can
cause
sparks, overheating,
orlire.
1.
Protect
yourself
and
others
from
flying
sparks
and hot
metal.
2.
Do
not
weld where
flying
sparks
can
strike
flammable
material.
3.
Remove
all 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
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.
lfdamaged,
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.
5.
Watch for
fire,
and
keep
a
fire
extinguisher
nearby.
6.
Be
aware
that
welding
on a
ceilIng,
floor,
bulkhead,
or
partition
can cause
fire
on
the
hidden
side.
7.
Do
not
weld
on
closed
containers
such
as
tanks
or
drums.
8.
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.
11.
Wear oil-free
protective
garments
such
as
leather
gloves,
heavy
shirt,
cuffless
trousers,
high
shoes,
and
a
cap.
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
Weld
ing Society
Standard
AWS
F4.1,
from American
Welding Society,
550
N.W.
LeJeune
Ad,
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
forSafety
in
Welding
and
Cutting,
CSA
Standard
Wi
17.2,
from Canadian Standards
Association,
Standards
Sales,
178 Rexdale
Boulevard.
Rexdale,
Ontario,
Canada M9W
1
R3.
Safe
Practices
ForOccupationAndEducational
Eye
And
Face
Protection,
ANSI Standard
Z87.
i,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
Ref.
sri 2/92
SECTION
1

SPECIFICATIONS
i-i.
DutyCycleChart
1-2.
Volt-Ampere
Curves
SECTION
2
INSTALLATION
2-1.
Installing
Work
Clamp
2-2.
Installing
Welding
Gun
2-3.
Gun
Polarity
For
Wire
Type
2-4.
Installing
Gas
Supply
2-5. Electrical
Service Guide
2-6.
Selecting
A
Location
And
Connecting
Input
Power
2-7.
Threading
And
Feeding Welding
Wire
2-8. Weld
Parameters
SECTION
3-OPERATION
SECTION
4
MAINTENANCE
&
TROUBLESHOOTING
4-1.
Overload Protection
4-2.
Drive
Assembly
Maintenance
4-3.
Gun Maintenance
4-4.
Troubleshooting
SECTION 5-ELECTRICAL
DIAGRAM
12
SECTION
6
PARTS
LIST
Figure
6-1. Main
Assembly
Figure
6-2.
MWG-16OMA
Gun
2
2
3
3
4
4
5
6
7
8
9
10
ii
ii
13
14

SECTION
1

SPECIFICATIONS
Table
1-1.
Welding
Power
Source
SpecificatIons
Type
Of
Output
Rated Weld
Output
Type
Of
Input
Power
Input
Amperes
At Rated
Output
KVAIKW
Used
At
Rated
Output
Max.
Open-Circuit
Voltage
Control
Circuit
Voltage
At Gun
Welding
Processes
Calculated
Speed Range
At
No Load
Wire Diameter
Range
Overall
Dimensions
Weight
Welding
Gun
Description
Direct Current/Constant
Voltage
(DC/CV)
130
Amperes,
20
Volts
DC,
30%
Duty
Cycle
Single-Phase;
60
Hz;
At 230
Volts
AC
20
A
At 230
V
4.7
kVAI4
kW
33
Volts DC
24
Volts DC
Gas
Metal Arc
(GMAW)
And Flux
Cored
Arc
Welding
(FCAW)
126
To 722
ipm
(3.2
To
18.3
mpm)
.02310
.035
Ifl
(0.58100.89mm)
Solid/Stainless
Steel;
.030
To
.045 in
(0.8
To
1.1
mm)
Flux
Cored/Aluminum
Length:
16-112
in
(419
mm); Width:
9-1/2 in
(241 mm);
Height:
17
in
(432
mm)
Net:
73 lb
(33
kg)
160
Amperes
At
60%
Duty
Cycle
Using
CO2 Shielding
Gas
lOft
(3m)
1-1.
Duty
Cycle
Chart
41
CAUTION
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.
wfwłm8.1 10/91
Duty
cycle
is
how
long
the
unit
can
300
250
_
~
a a
a
E
operate
within
a
ten
minute
period
without
causing
overheating
or
damage.
200
=
= = :
:
:
:
E
Thisunitisratedat3o%dutycycie
allowing
welding
3
minutes
out
of
(1)
150
W
~
a-
~100




~::::~~


-
-
-- -

:
:
: :
:

 .-
-

  
:
-
- 
~
-
:

-
everylOminutes.
.
This
gun
is
rated
at
60%
duty
cycle
when
using CO2
shielding
gas
and
30%
when
using
mixed
shielding
gas.
o

   -
- -
-
- 
-

::i
10
15
20 2530
40
50 607080100
%
DUTY CYCLE
sbl.3
1O/91S8-180844
Figure
1-1.
Duty
Cycle
Chart
Rated
Output
(Air-Cooled)
Cable
Length
OM-185 356
Page
1

1-2.
Volt-Ampere
Curves
10
0
SECTION
2
-
INSTALLATION
5
50
100 150
200
250
LOAD
AMPS
0
I
I
I I
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.
ssbl.1
1O/91SB-180765
FIgure
1-2.
Volt-Ampere
Curves
2-1.
Installing
Work
Clamp
1
Insulator
2
Bolt
3
Smaller
Hole
4
Work
Clamp
Tabs
Bend
tabs
around
work
cable.
5
Work
Cable
From
Unit
6
Nut
2
3
4
Tools
Needed:
~
3/8,7/161n
Figure
2-1.
Installing
Work
Clamp
ST-025
190D
OM-185
356
Page
2

2-2.
Installing
Welding
Gun
FIgure
2-2.
Gun Connections
2-3.
Gun
Polarity
For
Wire
Type
WARNING
Tools
Needed:
c::::::zJ::==::c
3/8
in
Figure
2-3.
Gun
Polarity
Connections
3
1
Gun
Securing
Nut
2
Drive
Assembly
3
Gun End
Loosen
securing
nut.
Insert
end
through
front
panel
opening
until
it
bottoms
against
drive
assembly.
Tighten
nut.
4
Gun
Trigger
Plug
Insert
plug
into
receptacle,
and
tighten
threaded
collar.
Close
door.
Tools
Needed:
~
5/16 in
Ref. ST-155
50~A
__
)
_
_____
~
(
_________
r ~ r
j
i
4
ELECTRIC SHOCK
can
kill.
~\

Do
not
touch
live electncal
parts.

Turn
Off
welding
power
source,
and
disconnect
input
power
before
inspecting
or
installing.
swaml.1
2/93
I
Polarity Changeover
Label
1
2
Polarity
Jumper
Links
Always
read
and
follow
welding
wire
manufacturers
recom
mended
polarity.
Close
door.
Ref. ST-155
506-A
2
OM-185 356
Page
3

2-4.
Installing
Gas
Supply
4~
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
CJ
L.
other
stationary
support.
BUILDUP
OF
SHIELDING
GAS
can
harm
health
or
kill.

Shut
off
shielding
gas
supply
when
not
in
use.
wam4.1
9/91
Figure
2-4.
Typical
CO2
Regulator/Flowmeter
Installation
2-5.
Electrical
Service
Guide
Input
Voltage
230
Input
Amperes
At
Rated
Output
20.5
Max Recommended
Standard
Fuse
Or
Circuit
Breaker
Rating
In
Amperes
25
Mm
Input
Conductor
Size In
AWG/Kcmil
14
Max Recommended
Input
Conductor
Length
In
Feet
(Meters)
64(19)
Mm
Grounding
Conductor
Size
In
AWGIKcmiI
14
Reference:
1996
National
Electrical
Code
(NEC)
S-0092-J
1
Chain gas
cylinder
to
running
gear,
wall,
or
other
stationary
support
so
cylinder
cannot
fall
arid
break off
valve.
2
3
1
Cap
2
Cylinder
Valve
3
Cylinder
4
Regulator/Flowmeiter
5
Gas
Hose
Connection
Fitting
has
5/8-18
right-hand
threads.
n-.

OR
6
Flow
Adjust
Typical
flow
rate
is
20
cfh
(cubic
feet
per
hour).
Check
wire
manufacturers
recommended
flow
rate.
Argon
Gas Or
Mixed
Gases
~
.2
Make
sure
flow
adjust
is
closed
when
opening
cylinder
to
avoid
damage
to
the
flowmeter.
7
CO2
Adapter
8
0-RIng
Install
adapter
with
0-ring
between
regulator/ftowmeter
and
CO2
cylinder.
Tools Needed:
3
1-1/8,5/8in
ssbal

5/94

ST-158
697-A
I
Rcf.
ST-149
627-B
OM-1
85
356
Page
4

2-6.
Selecting
A
Location
And
Connecting
Input
Power
a
WARNING
ELECTRIC
SHOCK
can
kill.
~

Do
not
touch live
electrical
parts.
S
Turn Off
welding
power
source,
and disconnect
input
power
before
inspecting
or
installing.
swaml.1
V93
1
Rating
Label
Supply
correct
input
power.
2
Plug
Figure
2-5.
Connecting Input
Power
3
Receptacle
Ref.
ST-801
785 / Ref.
ST-80t
504
4
Connect
plug
to
receptacle.
4
Une
Disconnect
Device
See Section
2-5.
A Special
Installation
may
be
required
where
gasoline
or
volatile
liquids
are
present

see
NEC
ArtIcle
511
or
CEC
Section
20.
Li
A
Always
connect
grounding
conductor
first.
~=GNDIPE
A
Do
not
move or
operate
unit
where
it
could
tip.
OM-185
356
Page
5

2-7.
Threading
And
Feeding
Welding
Wire
£~
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.
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
threadinq
welding
wire.
1
Wire
Spool
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,
cutoff 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.
.

TO USE
1
LB
SPOOL:
ELECTRIC
SHOCK
can
kill.

Do
not
touch
live
electrical
parts.
j
H

OT SURFACES
can
burn
skin.
Allow
gun
to
cool
before
touching.
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.
s~m5.1
10/91
/swam2.i
9/91
TO USE
Standard Wire
Reel:
Part
No.
135615
Lay
gun
cable
out
straight.
7
Nozzle
23
8
Contact
Tip
Remove
nozzle and
contact
tip.
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
tip
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.
Close door.
Tools Needed:
~
9/16
in
9
8
7
Figure
2-6.
Feeding
Welding
Wire
ST-BOO
316
/ Ref.
ST-
155 505-A
/
Ref. ST-i
55
504-A I
S-0627-A
OM-l85
356
Page
6

2-8. Weld
Parameters
Wire
Type,
Shielding
Gas,
And
Flow Rate
Wire
Diameter
(inch)
Operator
Controls
Material
Thickness
1/4
in.
(6.4
mm)
3/16
in.
(4.8 mm)
1/8
in.
(3.2
mm)
14
ga.
16
ga.
18
ga.
2Oga.
22
ga.
E7OS-6
CO2
2Ocfh
.023
Voltage
Tap

5
4
3
3 2
2
1
Wire
Speed

70
60 50 30
20
5
0
.030
Voltage
Tap
65
4
3 3 2
1
~


Wire
Speed
60
45
4.0
35
30 25 20

.035
Voltage
Tap
6 5
4
3 22
2 ~
Wire
Speed
30 20
20 20
20
15
5

E7OS-6
75%
Argon
25%
CO2
2ocfh
.023
Voltage
Tap
6
5
4
3
3 2
2
1
Wire
Speed
100 90
75 60 50 35
20
10
.030
Voltage
Tap
6
5
4
3
3 2
11
Wire
Speed
70
60
50 40
30
20
10
0
.035
Voltage
Tap
6
5
5
4
3
2
2
.
Wire
Speed
50
45
40 30
25
25
10

E71T-GS
Flux
Core
.030
Voltage
Tap
6 6 5
4
3
2
2

Wire
Speed
50
45
30
20
20
10 10


.035
Voltage
Tap
6
6 5
4
3

 

Wire
Speed
40
40
30 20 20
  
ER 308
Stainless
Steel
Tn-Mix
2ocfh+
.023
Voltage
Tap

5
4
4
3 333
Wire
Speed


100
90 75 60
50
40
25
.030
Voltage
Tap


6
5
4
3
3



Wire
Speed

75
70 60 50
40


Do
not
change Voltage
switch
position
while
welding.
Wire
Speed
value
in
Table
is
a
starting
value
only
and
WIre
Speed
control
setting
can
be
fine
tuned
during
welding.
S-181
186
OM.185
356
Page
7

MOVING PARTS
can
cause
injury.

Keep
away
from
pinch
points
such
as
drive rolls.

Keep
all
doors,
panels,
covers,
and
guards
closed
and
securely
in
place.
READ
SAFETY
BLOCKS
at
beginning
of
manual
before
proceeding.
ARCING
can
damage
switch.

Do
not
change
Voltage
switch
position
while
welding.
Arcing
inside
switch
can
damage
contacts,
causing
switch
to
fail.
SECTION
3-
OPERATION
WIRE
SPEED
VOLTAGE
Figure
3-1.
Controls
OM-185
356
Page
8

SECTION
4-
MAINTENANCE
&
TROUBLESHOOTING
AA
WARNING
ELECTRIC SHOCK
can
kill.

Do
not
touch
live electiical
parts.

Turn
Off
welding
power
source,
and
discc
Input
power
before
inspecthg, maintaining,
servicing.
HOT PARTS
can
cause
severe
burns.

Allow
cooling
period
before
maintaining
or
servicing.
MOVING
PARTS
can
cause
injury.

Keep
away
from
moving
parts.

Keep
away
from
pinch points
such
as
drive
rolls.
eshooting
to
be
performed
swam8.2~
2/93
A.
Overheating
Table
4-1.
Maintenance Schedule
Thermostat
TP1
protects
the
unit
from
damage
due
to
overheating.
If main
transformer
gets
too
hot,
TP1
opens
and
weld
output stops,
but
fans
keep running
to
cool
transformer.
Wait
several minutes
before
trying
to
weld.
B.
Motor
Fuse
Fl
If
Fl
opens,
wire
drive
motor
shuts
down.
Replace
Flit
open.
Reinstall
wrapper
and
handle,
and
latch door.
Tools
Needed:
lime
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
I
~r1.~jj(~

READ
Sectio
SAFETY
n
4
befor
BLOCKS
at
start
of
e
proceeding.
____
AA
CAUTION
STATIC ELECTRICITY
can
damage
parts
on
circuit boards.

Put
on
grounded
wnst
strap
BEFORE
handling
boards
or
parts.
twam5.1~
9191
Turn Ott
and
unplug
unit.
Unlatch
door,
remove
handle,
and
remove
door/wrapper.
1
Circuit
Board
PCi
2
Fuse
Fl
(See
Parts
List
For
Rating)
Figure
4-1.
Fuse Fl Location
~3
3/8
in
Ref.
91-801 785
OM-185 356
Page
9

C.
Short
Circuit
Shutdown
If
contact
tip
is
shorted
and
sticks
to
workpiece,
the unit shuts
down,
but
fan
runs.
To
resume
operation,
release
gun
trigger,
turn
Off
unit,
and
remove
contact
tip
from
workpiece.
Check
contact
tip
and
replace
if
damaged.
Turn
On
unit
to
continue
operation.
4-2.
Drive
Assembly
Maintenance
_________
READ SAFETY
BLOCKS
at
start
of
Section
4
before
proceeding.
Turn Oft
and
unplug
unit.
1
WIre
Spool
2
Gun
Contact
lip
Cut
welding
wire
off
at
contact
tip.
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
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
desired
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
Wire
inlet
Guide
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
2-7).
Close
door.
Tools
Needed:
~===-
5/~1
ST.1555C4-A/ST-154
199
Figure
4-2.
Drive
Assembly
Maintenance
OM-185
356
Page
10

4-3.
Gun
Maintenance
4-4.
Troubleshooting
Replace
contact
tip.
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.
READ
SAFETY
BLOCKS
at
start
of
Section
4
before
proceeding.
sw~m10.1
10/91
1
4
5
2
7
Turn Off
and
unplug
unit.
1
Wire
Spool
Cut
welding
wire
off
at
contact
tip.
Retract wire
onto
spool
and
secure.
2
Gun
Securing
Nut
Disconnect
trigger
leads.
Loosen
nut
and
remove
gun
and
trigger
leads.
3Nozzle
4
Contact
lip
5
Head Tube
6 Liner
Collet
Disassemble
gun
as
shown.
7
Liner
Pull
liner from
this
end.
Blow
gun
casing
out
with
compressed
air.
Insert
new
liner into
gun
casing
until
even
with end of
head
tube.
Install
collet
onto
liner.
Install
contact
tip
and
nozzle.
Insert
gun
into feeder
and mark
where
liner
touches drive
roll.
Remove
gun
and
cut
liner
oft.
ReInstall
gun
so
that liner
is
as
close
as
possible
to
drive
rolls
without
touching.
Thread
welding
wire
(see
Section
2-7).
Close
door.
Ref.
ST-t55
506A
/
5T-155
509-A
Tools
Needed:
~
3/8,5/16
in
Figure
4-3.
Gun Maintenance
Welding
Trouble
No
weld
output;
wire does
not
feed.
j-...~
Secure
power
cord
plug
in
receptacle.
READ
SAFETY
BLOCKS
at
start
of
Section
4
before
proceeding.
Remedy
-...~
-~L__4-lB
-~L


-..J
Section
2-6


2-2
Motor fuse
Fl
open,
replace
Fl.
Replace
building
line
fuse
or
reset
circuit
breaker
it
open.
Secure
gun
trigger
leads
or
repair
leads,
or
replace trigger
switch.
LN~e~~Put;_wire
feeds.
No
weld
output;
wire
does not
feed;
fan
~

-.4
Thermostat
TP1
open
(overheating).
Allow
fan
to
run;
the
thermo-
 
-~
4-1
A
motor
continues
to
run.
]
stat
will
close
when
the unit has cooled.
Low
weld
output.
F-.

-~
Connect
work
clamp
to
get
good
metal
to
metal contact.
1-..
Figure
3-1
H-.~
4-3

-
Connect
unit
to
proper
input voltage
or
check
for
low
line
voltage.
J

-..J
2-6
OM-185
356
Page
11

Wire
Drive/Gun
Trouble
Remedy
Section
SECTION
5-
ELECTRICAL
DIAGRAM
Figure
5-1.
Circuit
Diagram
Electrode
wire
feeding.
stops
during
~

-.
welding.
I
Straighten
gun
cable
and/or
replace
damaged
parts.
Adjust
drive
roll
pressure.
Readjust
hub
tension.
Replace
contact
tip
if blocked.
Clean
or
replace
wire inlet
guide
or
liner
if
dirty
or
plugged.
Replace
drive
roll
or
pressure
bearing
if
worn or
slipping.
Check
and
replace
El.
Secure
gun
trigger
leads
or
repair
leads.
or
replace trigger
switch
Check
and clear
any
restrictions
at
drive
assembly
and
liner
Have
nearest
Factory
Authorized
Service
Station/Service
Distributor
check
drive
motor.
I~~<~2

~3-5
-<krc2-1
SB-180
784-B
OM-185
356
Page
12

SECTION
6-
PARTS LIST
Figure
6-1.
Main
Assembly

0)
C)
1
ST-801
784
0)
CM
(0
CM
I.
Co
C~)
C.,
C.,
CM
CM
OM-185
356
Page
13

Parts
For
Main
Assembly
NOTE:
All
items
indented
by
a
dof~s)
are
included
with the
item
listed
directly
above.
Item
Part
No.
No.
Description
126 838
Drive
Assembly
1
090416
Hinge
Pin
2
124817
DrlveHousing
3
151
828
Cotter
Hair
Pin
4
112031
PressureLever
5 090443
Beaflng
111
622
Spacer
6
092237
Knob
7
090415
Spring
8
085
244
Cupped
Washer
9
085242 Fastener
10
010224
.SprmgPin
11
058 549 Wire
Guide
12
149 332
Hose
Clamp
13
147635
Hose
14
154827
Drive Roll
15
602169
Set Screw
16
129
893
Insulator
17
173446 Drive Motor
18
153727
Baffle
19
111 929
Hub
135615
Bushing,
.390
ID
x
.750
OD
183 312
Adapter
ring,
wire
spool
20
010910 Washer
21
073355
Spring
22 010909
Nut
23
111
998 Cotter Hair
Pin
24 120675
Bracket
Item
Part
No.
No.
Description
25
117014
Fan Motor
26
005656
Fan Blade
27
089899
Latch
28
153729
Handle
154596
Cap,
Handle
29
134 464
Warning
Label
30
+153
724
Wrapper
31
153722
Side
Panel
32
176
170
Thermostat,
NC
33
180786
Transformer
34
181 649
Resistor
35
090288
Varlstor
36
162245
Capacitor
37
002160
Clamp
38
180793
Stabilizer
39
019663
Foot
40
600 325
Cable
026
843
Insulator
41
010368
Clamp
42
110740
MWG16OM-A(Rg6-2)
43
Case
w/Cmpts
128
751
Gas
Valve
605 227
.
Nut,
gas
valve
152118
CordSet
111 443
Bushing,
cord
set
000
101
Rheostat
097 922
Knob
116830
.
Rocker
Switch,
DPST
180 777
.
Rotary
Switch
w/Knob
185265
Case
184994
.
Nameplate
111
644
.
Bushing,
.B75mtg
048 282
.
Connector
172543
.
Circuit
Card
073
426
.
Fuse,
slo-blo 5A
080
388
Relay
173299
.
.
ClIp.
holddown
relay
113
149
Connector
110 160
.
Connector,
6skt
079
747 .
Sockets
134201
.
Stand-Off
Support
44
116619
Terminal
Assembly
174
504 Link
45
175994
Spacer
46 180791
Rectifier
47
108358
Contactor
173374
Regulator/Flowmeter
183581
Hose,gas
Recomrnended
Spare
Parts.
When
ordering
a
component
originally
dis
playing
a
precautionary
label,
the
label
should
also
be
ordered.
Be
sure
to
provide
Model
and
Serial
Number
when
ordering
replacement
parts.
Item
Part
No. No.
Description
1
110793
Handle
Assembly,
black
2 110795 Head
Tube
3
110780
Nut
4
110779
Jacket
5
110781
Stop
6 128878
Adapter
7
118571
Spring
8 154826
Contact
Tip,
.023
(6)
8 154825
Contact
Tip,
.030
(6)
8 154824
Contact
Tip,
.035
(6)
9 154822
Nozzle,
1/2
orf
(1)
9
154821
NozzIe,3/8ort(1)
9

154
820
Nozzle,
flat
spot
(1)
10
110 794
Trigger
Switch
Assembly
11
080565
Terminal
12 110
792
Cable/Conduit
13
110797 Sleeve
14 167440
Liner,
.023-.035
15
110 784
Collet,
.035
16
079974
0-Ring,
.500
17 110 796
Connector
18
079
878
Connector
& Pins
19 048 834
Connector
Item Part
No. No.
Description
15
16
2
17
18
 OPTIONAL
ST-lb
832-D
Figure
6-2.
MWG16OM~A
Gun
(Fig
6-1 Item
52)
OM-185
356
Page
14