AUTO ARC MW 4110 User manual

AUTO
ARCJ
September
1990 FORM:
OM-112
875D
Effective
With
Serial
No.
KA870779
MODEL:
MW
4110
MW
4230
OWNERS
MANUAL
IMPORTANT:
Read
and
understand the entire
contents
of
this
manual,
with
special emphasis
on
the
safety
material
throughout
the
manual,
before
MILLER
ELECTRIC
Mig.
Co.
AM~G~Ud..Corr~any
Installing,
operating,
or
maintaining
this
equipment.
This
unit
and these
Instructions
are
for
use
only
by
persons
trained and
experienced
in
the
Safe
1079
Appleton,
WI
54912 USA
operation
of
welding
equipment.
Do
not
allow
untraIned
persons
to
install,
Tel. [phone]
operate,
or
maintain
this
unit.
Contact
your
dIstributor
If
you
do
not
fuliy
understand
these
Instructions.
18-112
943-A

ONEYEAR
LIMITED
WARRANTY
EFFECTIVE:
FEBRUARY
11,
1989
This
warranty
supersedes
alt
previous
AUTO
ARC
warranties
and
is exclusive with
no
otherguarantees
orwarranties
expressed
or
implied.
COVERAGE
-
MILLER Electric
Mfg.
Co.
warrants to the
buyer
who
purchases
this
AUTO
ARC
Welder
(~WeIder)
for
personal,
family
or
household
purposes
(Consumer)
that
this
Welderwill
be
free
from
defects
in
material and
workmanship
for
a
peflod
of
one
year from
the
date of
purchase.
This
warranty
covers
only
the
onginal
purchaser
of
this
Welder.
MILLER
Elec
tric
does
not
authorize
any party, including
its
authorized
dis
tributors,
to
offer
any
other
warranty
on
behalf
of
MILLER
Elec
tric.
Upon
expiration
of
the
warranty
period.
MILLER
Electric
shall
have
no
further
liability
related
to the
Welder,
except
on
warranty
claims
made
during
the
warranty
period.
No
warranty
is made
by
MILLER
with
respect
to
engines,
trade
accessories
orotheritems
manufactured
by
others.
Such
engines,
trade
ac
cessories
and
other
items
are
sold
subject
to the
warranties of
their
respective
manufacturers,
if
any.
All
engines
are
war
ranted
by
their manufacturer
for
two
years
from
date of
original
purchase,
except
Deu~
engines
which
have
a
one
year,
2000
hour
warranty.
MILLER shall
be
required
to honor
warranty
claims
on
war
ranted
Equipment
in the
event
of
failure
resulting
from
a
defect
within
the
following
periods
from
the
date
of
delivery
of
Equip
ment
to
the
original
user:
1.
Arc
welders,
power
sources,
and
components
...
1
yew
2.
Original
main
power
rectifiers
3
years
(labor

1
year
only)
3.
All
welding
guns,
feeder/guns
and
torches
90
days
4.
Replacement
or
repair
parts,
exclusive
of labor
.
60
days
5.
Batteries
6
months
provided
that
MILLER
is
notified
in
writing
within
thirty
(30)
days
of
such failure.
WHAT
IS
NOT
COVERED

This
warranty
does
not
extend
to
any
Welder
subjected
to
misuse,
neglect,
accident,
or
in-
warranty
repair
by
anyone
except
MILLER
Electric
or
its
autho
rizedservicestations.
Further,
thiswarrantyonlyextendstothe
original
purchaser
of
this Welder.
In
the
case
of
MILLERs
breach of
warranty
or
any
other
duty
with
respect
to
the
quality
of
any
goods,
the
exclusive
remedies
therefore
shall
be,
at
MILLERs
option
(1)
repair
or
(2)
replace-
mentor,
where
authorized
in
wflnng
by
MILLER
in
appropriate
cases,
(3)
the
reasonable
cost
of
repair
or
replacement
at
an
authorized
MILLER
service
station
or
(4)
payment
of
or
credit
for
the
purchase
price
(less
reasonable
depreciation
based
upon
actral
use)
upon
return
of
the
goods
at
Consumers
risk
and
expense.
MILLERs
option
of
repair
or
replacement
will
be
F.O.B.,
Factory
at
Appleton,
WI
or
FOB,
at
a
MILLER
autho
rized
service
facility,
therefore,
no
compensation
for
transporta
tion
costs
of
any
kind will be alowed.
Upon
receipt
of
notice
of
apparentdefect
orfailure,
MILLER
shall instruct
the
claimant
on
the
warranty
claim
procedures
to
be
followed.
THIS
WARRANTY IS
OFFERED
IN
LIEU
OF ANY
OTHER
EXPRESS
WARRANTY;
AND,
EXCEPT
TO
THE EXTENT
PROHIBITED
BY
APPLICABLE
LAW.
THE DURATION
OF
ALL
IMPUED
WARRANTIES.
INCLUDING BUT
NOT
LIMITED
TO THE IMPUED
WARRANTIES
OF
MERCHAN
TABIUTY
AND
FITNESS
FOR
A
PARTiCULAR
PURPOSE.
IS
UMITED
TO
THE
DURATION
OF
THIS WARRANTY.
ANY
EXPRESS
WARRANTY
NOT
PROVIDED
HEREIN
AND
ANY
IMPLIED
WARRANTY,
GUARANTY
OR
REPRE
SENTATION
AS TO
PERFORMANCE,
AND
ANY
REMEDY
FOR
BREACH
OF
CONTRACT
WHICH.
BUT
FOR
THIS
PROVISION,
MIGHT
ARISE
BY
IMPUCATION,
OPERATION
OF
LAW,
CUSTOM
OF
TRADE
OR
COURSE
OF
DEALING,
INCLUDING
ANY
IMPUED
WARRANTY OF
MERCHANT
ABIUTY
OR
OF
FITNESS
FOR
PARTICULAR
PURPOSE.
WITH
RESPECT
TO
ANY
AND
ALL
EQUIPMENT
FUR
NISHED
BY
MILLER
IS
EXCLUDED
AND
DISCLAIMED
BY
MILLER.
Some
states
do not
allow
limitations
on
how
long
an
implied
warranty
lasts,
so
the
above
limitation
may
not
apply
to
you.
This
warranty
gives
you
specific
legal
rights,
and
you may
also
have other
rights
which
vary
from
state
to
state.
THE
PURCHASERS
REMEDIES
FOR
A
DEFECTIVE
WELDER,
TO
THE
EXTENT
PERMITrED
BY
APPLICABLE
LAW,
ARE UMITED
TO
THE
REMEDY PROVIDED
BY
THIS
WARRANTY.
TO
THE
EXTENT
ENFORCEABLE UNDER
APPUCABLE
LAW,
MILLER ELECTRIC
SHALL
IN NO
EVENT
BE
LIABLE
FOR
CONSEQUENTiAL,
INCIDENTAL
OR SPECIAL
DAMAGES
ARISING
OUT
OF THE USE
OF.
OR
INABILITY
TO
USE,
THE
WELDER,
WHETHER BASED
ON
BREACH
OF
THIS
WARRANTr~
MILLER
ELECTRICS NEG
LIGENCE
OR
OTHER
TORT,
OR
ON ANY
THEORY
OF
STRICT
LIABIUTY.

-
OM.1128750-e,gO
RECEIVING-HANDLING
Before
unpacking equipment,
check
carton
for
any
dam- Use the
following
spaces
to
record
the
Model
Designa
age
that
may
have
occurred
dunng shipment.
File
any
tion
and
Serial
or
Style
Number
of
your
unit.
The
infor
claims
for
loss
or
damage
with
the
delivering
carrier.
mation
is
located
on
the
data
card
or
the
nameplate.
Assistance
for
filing
or
settling
claims
may
be
obtained
frorrt
the
distributor
and/or the
equipment
manufactur-
Model
__________________________________________
ers
Transportation
Department.
Serial
or
Style
No.
______________________________
When
requesting
information
about
this
equipment,
al
ways
provide
the
Model
Description
and
Serial
or
Style
Date
of
Purchase
______________________________
Number.
TABLE
OF
CONTENTS
Section
No.
Page
No.
SECTION
1

SAFETY
RULES
FOR
OPERATION OF
ARC
WELDING
POWER
SOURCE
1-1.
Introduction
1
1-2.
General
Precautions
1
1-3. Arc
Welding
4
1-4.
Standards
Booklet Index 5
SECTION
2-SAFETY
PRECAUTIONS
AND
SIGNAL WORDS
2-1.
General
Information
And
Safety
6
2-2.
Safety
Aert
Symbol
And
Signal
Words
6
SECTION
3
SPECIFICATIONS
3-1.
Volt-Ampere
Curves
8
3-2.
Duty
Cycle
8
3-3.
Description
9
3-4.
Supplied
Equipment
9
3-5.
Additional
Required Equipment
9
3-6.
Optional Equipment
10
3-7.
Consumable
Parts
10
SECTION
4INSTALLATION
4-1.
Site
Selection 11
4-2.
Shielding
Gas
Installation
11
4-3.
Work
Clamp
installation
11
4-4.
Gun
Polarity
Selection
Procedure
12
4-5.
Welding
Gun
Installation
13
4-6.
Welding
Wire
Spool
Installation
13
4-7.
Electrical
Input
Connections
13
4-8.
Welding
Wire
Installation
14
SECTION
5-OPERATOR
CONTROLS
5-1.
Power Switch
16
5-2.
ThicknessNo
Its Switch
16
5-3.
Fine
Tuning/Wire
Speed
Control
16
5-4.
Welding
Gun
Receptacle
16

Section
No.
Page
No.
SECTION
6-
SEQUENCE
OF OPERATION
6-1.
Gas
Metal
Arc
Welding
(GMAW)
17
6-2.
Shutting
Down
18
SECTION
7-
MAINTENANCE
&
TROUBLESHOOTING
7-1
Routine
Maintenance
20
7-2.
Overload Protection
21
7-3.
Replacing
Drive Roll
21
7-4.
Replacing
Pressure
Bearing
22
7-5.
Replacing
Wire Inlet
Guide
22
7-6.
Realigning
Drive
Housing
22
7-7. Circuit Board
Replacement
22
7-8.
Welding
Gun
Inspection
And
Upkeep
23
7-9.
Contact
Tube
Replacement
24
7-10.
Gun
Liner
Replacement
24
7-11.
Troubleshooting
25
SECTION
8-
ELECTRICAL DIAGRAMS
Diagram
8-1. Circuit
Diagram
For MW
4110
Models
27
Diagram
8-2.
Circu~
Diagram
For MW
4230
Models
27
Diagram
8-3.
Circuit
Diagram
For
MW
4110
Motor
Control
Board
PCI
28
Diagram
8-4. Circuit
Diagram
For
MW
4230
Models
Motor
Control
Board PCi
28
Diagram
8-5.
Wiring Diagram
For
MW
4110
Models
29
Diagram
8-6.
Wiring Diagram
For
MW
4230
Ampere
Models
30
SECTION
9
WELDING
TECHNIQUES
&
TROUBLESHOOTING
9-1. Gas
Metal Arc
Welding
(GMAW)
-
Continuous Seam
31
9-2.
Troubleshooting
The
Gas
Metal Arc
Welding
(GMAW)
Process
....
32
SECTION
10

AUTO
BODY
REPAIR
APPLICATION
10-1.
Pointers
For
Welding
Auto
Body
Sheet
Metal
36
10-2.
Procedure
For
Welding
Mild
Steels
36
10-3.
Procedures
For
Welding
Door
Panels
36
10-4.
How To
Prevent
Glass
Breakage
And
Spatter
On
Windows
37
10-5.
Procedures
For
Welding
Fenders
And
Quarter
Panels
37
10-6.
Welding
Frames
And
High
Strength
(HSS)
Steels
37
SECTION
11

PARTS
LIST
Figure
11-1.
Main
Assembly
(Auto
Arc MW
4230
Illustrated)
38
Figure
11-2.
Drive
Assembly,
Wire
41
Figure
11-3.
Circuit
Card,
Motor
Control PCi
42
Figure
11-4.
Circuit
Card,
Motor
Control PCi
44
Figure
11-5.
Exploded
View
01
GA-16C Gun
46
LIST
OF CHARTS
AND
TABLES
Table
3-1.
Specifications
7
Chart
3-1.
Volt-Ampere
Curves 8
Chart
3-2.
Duty
Cycle
8
Table
4-i.
Line
Disconnect
Or
Supply
Circuit
Fuse
Size
14
Table
6-1.
Suggested
Settings
For
Welding
18
Table
7-i.
Maintenance
Schedule
20
Table
7-2.
Troubleshooting
26

SECTION
1
-
SAFETY
RULES
FOR
OPERATION
OF
ARC
WELDING
POWER
SOURCE
1.1.
INTRODUCTION
We learn
by experience.
Learning
safety through
per
sonal
experience,
like
a
child
touching
a
hot
stove
is
harmftil,
wasteful,
and
unwise.
Letthe
experienceof
Oth
ers
teach
you.
Safe
practices
developed
from
experience
in
the
use
of
welding
and
cutting
are
described
in
this
manual.
Re
search,
development,
and field
experience
have
evolved reliable
equipment
and safe
installation,
opera
tion,
and
servicing
practices.
Accidents
occur
when
equipment
is
improperly
used
or
maintained. The
rea
son
for the
safe
practices
may
not
always
be
given.
Some
are
based
on
common
sense,
others
may
require
technical volumes
to
explain.
It is
wiser
to
follow
the
rules.
Read and
understand these safe
practices
before
at
tempting
to
install,
operate,
or
service
the
equipment.
Comply
with
these
procedures
as
applicable
to
the
par
ticular
equipment
used and
their instruction
manuals,
for
personal safety
and for the
safety
of
others.
Failure
to
observe these safe
practices
may
cause
seri
ous
injury
or
death. When
safety
becomes
a
habit,
the
equipment
can
be used with
confidence.
These safe
practices
are
divided into
two Sections:
1-General
Precautions,
common
to
arc
welding
and
cut
ting;
and 2-Arc
Welding
(and
Cutting)
(only).
Reference
standards:
Published
Standards
on
safety
are
also available
for
additional
and
more
complete
pro
cedures
than
those
given
in this
manual.
They
are
listed
in
the
Standards
Index
in
this manual.
ANSI
Z49.1
is
the
most
complete.
The
National
Electrical
Code,
Occupational
Safety
and
Health
Administration,
local
industrial
codes,
and
local
inspection
requirements
also
provide
a
basis
for
equip
ment
installation,
use,
and
service.
1-2.
GENERAL
PRECAUTIONS
Different
arc
welding
processes,
electrode
alloys,
and
fluxes
can
produce
different
fumes,
gases,
and
radiation
levels. In
addition
to
the
information
in
this
manual,
be
sure to
consult flux
and
electrode
manu
facturers
Material
Safety
Data
Sheets
(MSDSs)
for
specific
technical
data
and
precautionary
measures
concerning
their
material.
A.
Burn
Prevention
Wear
protective
clothing-gauntlet
gloves
designed
for
use
in
welding,
hat,
and
high
safety-toe
shoes.
Button
shirt
collar
and
pocket
flaps,
and
wear
cuffless
trousers
to
avoid
entry
of
sparks
and
slag.
Wear
helmet
with
safety
goggles
and
glasses
with side
shields
underneath,
appropriate
filter
lenses
or
plates
(protected
by
clear
cover
glass).
This
is
a
MUST
for
welding
or
cutting,
(and
chipping)
to
protect
the
eyes
from
radiant
energy
and
flying
metal.
Replace
cover
glass
when
broken,
pitted,
or
spattered.
See
1
-3A.2.
Avoid
oily
or
greasy
clothing.
A
spark
may
ignite
them.
Hot metal
such
as
electrode
stubs and
workpieces
should
never
be handled without
gloves.
Medical
first aid
and
eye
treatment.
First
aid
facilities
and
a
qualified
first
aid
person
should be available
for
each
shift unless
medical facilities
are
close
by
for
immediate
treatment
of flash burns
of
the
eyes
and skin
burns.
Ear
plugs
should
be
worn
when
working
on
overhead
or
in
a
confined
space.
A
hard
hat should
be
worn
when
others
work
overhead.
Flammable hair
preparations
should
not
be used
by
per
sons
intending
to
weld
or
cut.
B. Toxic Fume Prevention
Severe
discomfort,
illness
or
death
can
result
from
fumes,
vapors,
heat,
or
oxygen
enrichment
or
depletion
that
welding (or
cutting)
may
produce.
Prevent
them
with
adequate
ventilation
as
described
in
ANSI
Standard
Z49.1 listed
in
Standards
Index.
NEVER
ventilate with
oxygen.
Lead-, cadmium-,
zinc-,
mercury-,
and
beryllium-bear
ing
and similar
materials,
when welded
(or cut)
may
pro
duce harmful
concentrations of toxic
fumes.
Adequate
local exhaust
ventilation
must
be
used,
or
each
person
in
the
area as
well
as
the
operator
must
wear an
air-sup
plied
respirator.
For
beryllium,
both
must
be
used.
Metals
coated
with
or
containing
materials
that
emit toxic
fumes
should
not
be heated unless
coating
is
removed
from the work
surface,
the
area
is well
ventilated
and,
if
necessary,
while
wearing
an
air-supplied
respirator.
Work
in
a
confined
space
only
while it is
being
ventilated
and,
if
necessary,
while
wearing
an
air-supplied
respira
tor.
Gas
leaks
in
a
confined
space
should
be
avoided.
Leaked
gas
in
large
quantities
can
change
oxygen
con
centration
dangerously.
Do
not
bring
gas
cylinders
into
a
confined
space.
Leaving
confined
space,
shut
OFF
gas
supply
at
source
to
prevent
possible
accumulation of
gases
in
the
space
if
downstream
valves
have been
accidentally
opened
or
left
open.
Check
to
be
sure
that
the
space
is
safe before
re-entering
it.
Vapors
from chlorinated solvents
can
be
decomposed
by
the heat of the
arc
(or flame)
to
form
PHOSGENE, a
highly
toxic
gas,
and other
lung
and
eye
irritating
prod
ucts.
The
ultraviolet
(radiant)
energy
of the
arc can
also
decompose
trichloroethylene
and
perchloroethylene
va
pors
to
form
phosgene.
DO NOT WELD
or
cut
where
sol
vent
vapors
can
be drawn
into the
welding
or
cutting
at
mosphere
or
where the radiant
energy
can
penetrate
to
OM-112
875
Page
1

atmospheres ~,containing
even
minute
amounts
of
trichioroethylene
or
perchloroØthylene.
C. Fire
and
Explosion
Prevention
Causes
of
fire
and
explosion
are:
combustibles
reached
by
the
arc,
flame,
flying
sparks,
hot
slag
or
heated
mate
nal;
misuse
of
compressed
gases
and
cylinders;
and
stiorf
circuits.
BE AWARE
THAT
flying
sparks
or
falling
slag
can
pass
through
cracks,
along pipes,
through
windows
or
doors,
and
through
wall
or
floor
openings,
out
of
sight
of
the
goggled
operator.
Sparks
and
slag
can
fly
35
feet.
To
prevent
fires
and
explosion:
Keep equipment
clean
and
operable,
free of
oil,
grease,
and
(in
electncal
parts)
of
metallic
particles
that
can
cause
short
circuits.
If
combustibles
are
in
area,
do
NOT weld
or
cut.
Move
the
work
if
practicable,
to
an
area
free
of
combustibles.
Avoid
paint
spray
rooms,
dip
tanks,
storage
areas,
venti
lators.
If
the
work
cannot
be
moved,
move
combustibles
at
least
35
feet
away
out
of reach of
sparks
and
heat; or
protect
against ignition
with
suitable
and
snug-fitting,
fire-resistant
covers
or
shields.
Walls
touching
combustibles
on
opposite
sides should
not
be welded
on
(or
cut).
Walls,
ceilings,
and floor
near
work should
be
protected by
heat-resistant
covers or
shields.
Fire
watcher
must
be
standing
by
with
suitable
fire
extin
guishing
equipment
during
and
for
some
time
afterweld
ing
or
cutting
if:
a.
appreciable
combustibles
(including building
construction)
are
within 35 feet
b.
appreciable
combustibles
are
further
than
35
feet
but
can
be
ignited
by
sparks
c.
openings
(concealed orvisible)
in
floors
orwalls
within 35
feet
may expose
combustibles
to
sparks
d.
combustibles
adjacent
to
walls,
ceilings,
roofs,
or
metal
partitions
can
be
ignited
by
radiant
or
conducted
heat.
Hot
work
permit
should
be
obtained before
operation
to
ensure
supervisors
approval
that
adequate precautions
have
been
taken.
After
work is
done,
check that
area
is free of
sparks,
glowing
embers,
and
flames.
An
empty
container
that
held
combustibles,
or
that
can
produce
flammable
or
toxic
vapors
when
heated,
must
never
be welded
on
or
cut,
unless
container
has
first
been
cleaned
as
described
in
AWS
Standard
A6.O,
listed
7
in
Standards
index.
This
includes:
a
thorough
steam
orcausticcleaning
(or
a
solvent
or
water
washing,
depending
on
the
combusti
bles
solubility)
followed
by
purging
and
inerting
with
ni
trogen
or
carbon
dioxide,
and
using
protective equip-
menfas~
recommended
in
A6.O.
Waterfilling just
below
working
level
may
substitufe
for
inerting.
A
container
with unknown
contents
should
be cleaned
(see
preceding
paragraph).
Do
NOT
depend
on sense
of
smell
or
sight
to
determine
if it
is safe
to
weld
or
cut.
Hollow
castings
or
containers
must
be vented before
welding
or
cutting.
They
can
explode.
Explosive
atmospheres.
Never weld
or
cut
where
the
air
may
contain
flammable
dust,
gas,
or
liquid
vapors
(such
as
gasoline).
D.
Compressed
Gas
Equipment
Standard
precautions.
Comply
with
precautions
in
this
manual,
and
those
detailed
in
CGA
Standard
P-i
,
SAFE
HANDLING OF
COMPRESSED
GASES
IN
CYLIN
DERS,
listed
11
in
Standards
Index.
1.
Pressure
Regulators
Regulator
relief
valve is
designed
to
protect
only
the
regulator
from
overpressure;
it
is
not
intended
to
protect
any
downstream
equipment.
Provide
such
protection
with
one
or
more
relief
devices.
Never
connect
a
regulator
to
a
cylinder
containing
gas
other
than
that
for
which
the
regulator
was
designed.
Remove
faulty
regulator
from service
immediately
for
re
pair (first
close
cylinder
valve).
The
following
symptoms
indicate
a
faulty
regulator:
Leaks-if
gas
leaks
externally.
Excessive
Creep-if delivery
pressure
continues
to
rise
with downstream
valve
closed.
Faulty
Gauge-if
gauge
pointerdoes
not
move
off
stop
pin
when
pressurized,
nor
returns
to
stop
pin
after
pressure
release.
Repair.
Do
NOT
attempt
to
repair.
Send
faulty
regulators
for
repair
to
manufacturers
designated
repair
center,
where
special
techniques
and
tools
are
used
by
trained
personnel.
2.
Cylinders
Cylinders
must
be
handled
carefully
to
prevent
leaks
and
damage
to
their
walls,
valves,
or
safety
devices:
Avoid
electrical
circuit
contact
with
cylinders
including
third
rails,
electrical
wires,
or
welding
circuits.
They
can
produce
short circuit
arcs
that
may
lead
to a
serious acci
dent.
(See
1-3C.)
ICC
or
DOT
marking
must
be
on
each
cylinder.
It is
an
assurance
of
safety
when
the
cylinder
is
properly
han
dled.
Identifying
gas
content.
Use
only
cylinders
with
name
of
gas
marked
on
them;
do
not
rely
on
color
to
identify
gas
content.
Notify
supplier
if
unmarked.
NEVER
DEFACE
or
alter
name,
number,
orother
markings
on
a
cylinder.
It
is
illegal
and
hazardous.
Empties:
Keep
valves
closed,
replace
caps
securely;
mark
MT;
keep
them
separate
from
FULLS
and
return
promptly.
OM-112
875
Page
2

Prohibited
use.~Never
use a
cylinder
or
its
contents
ior
other than its intended
use,
NEVER
as a
support
or
roller.
Locate
or
secure
cylinders
so
they
cannot
be
knocked
over.
Passageways
and work
areas.
Keep
cylinders
clear
of
areas~where
they
may
be
struck.
Transporting
cylinders.
With
a
crane,
use a
secure
sup
port
such
as a
platform
or
cradle.
Do NOT
lift
cylinders
off
the
ground
by
their
valves
or
caps,
or
by
chains,
slings,
or
magnets.
Do
NOT
expose
cylinders
to
excessive
heat,
sparks,
slag,
and
flame,
etc.
that
may
cause
rupture.
Do
not
al
low
contents
to
exceed
130F. Cool
with
water
spray
where such
exposure
exists.
Protect
cylinders particularly
valves from
bumps,
falls,
falling objects,
and
weather.
Replace
caps
securely
when
moving cylinders.
Stuck
valve.
Do
NOT
use
a
hammer orwrench
to
open
a
cylinder
valve that
can
not
be
opened by
hand.
Notify
your
supplier.
Mixing
gases.
Never
try
to
mix
any gases
in
a
cylinder.
Never refill
any
cylinder.
Cylinder
fittings
should
never
be modified
or
exchanged.
3.
Hose
Prohibited
use.
Never
use
hose otherthan that
designed
for
the
specified
gas.
A
general
hose
identification
rule
is:
red for fuel
gas, green
for
oxygen,
and black
for inert
gases.
Use ferrules
or
clamps
designed
for the
hose
(not
ordi
nary
wire
or
other
substitute)
as
a
binding
to connect
hoses
to
fittings.
No
copper
tubing splices.
Use
only
standard brass fit
tings
to
splice
hose.
Avoid
long
runs
to
prevent
kinks
and abuse.
Suspend
hose off
ground
to
keep
it from
being
run
over,
stepped
on,
or
otherwise
damaged.
Coil
excess
hose
to
prevent
kinks and
tangles.
Protect
hose
from
damage
by
sharp edges,
and
by
sparks,
slag,
and
open
flame.
Examine
hose
regularly
for
leaks,
wear,
and loose
con
nections.
Immerse
pressured
hose
in
water;
bubbles
in
dicate
leaks.
Repair
leaky
or worn
hose
by
cutting
area
out
and
splic
ing
(1-2D3).
Do NOT
tape.
4.
Proper
Connections
Clean
cylinder
valve outlet of
impurities
that
may
clog
orifices
and
damage
seats
before
connecting
regulator.
Except
for
hydrogen,
crack valve
momentarily,
pointing
outlet
away
from
peo.ple
and
sources
of
ignition. Wipe
~with
a
clean lintless
c~om.
Match
regulator
to
cylinder.
Before
connecting,
check
that
the
regulator
label
and
cylinder marking
area,
and
thatthe
regulator
inlet
~nd
cylinderoutlet
match.
NEVER
CONNECT
a
regulator
designed
for
a
particular
gas
or
gases
to
a
cylinder
containing
any
other
gas.
lighten
connections. When
assembling
threaded
con
nections,
clean and smooth
seats
where
necessary.
Tighten.
If
connection
leaks,
disassemble,
clean,
and
retighten using
properly
fitting
wrench.
Adapters.
Use
a
CGA
adapter
(available
from
your
sup
plier)
between
cylinder
and
regulator,
if
one
is
required.
use
two
wrenches
to
tighten
adapter
marked
RIGHT
and
LEFT
HAND
threads.
Regulator
outlet
(or hose)
connections
may
be identified
by right
hand
threads for
oxygen
and left hand threads
(with
grooved
hex
on
nut
or
shank)
for fuel
gas.
5.
Pressurizing
Steps:
Drain
regulator
of residual
gas
through
suitable
vent
be
fore
opening cylinder
(or
manifold
valve)
by
turning
ad
justing
screw
in
(clockwise).
Draining
prevents
exces
sive
compression
heat
at
high
pressure
seat
by
allowing
seat to
open
on
pressurization.
Leave
adjusting
screw
engaged
slightly
on
single-stage
regulators.
Stand
to
side of
regulator
while
opening cylinder
valve.
Open
cylinder
valve
slowly
so
that
regulator
pressure
in
creases
slowly.
When
gauge
is
pressurized
(gauge
reaches
regulator
maximum)
leave
cylinder
valve
in
fol
lowing position:
For
oxygen,
and inert
gases,
open
fully
to
seal
stem
against
possible
leak.
For
fuel
gas,
open
to
less than
one
turn to
permit quick
emergency
shutoff.
Use
pressure
charts
(available
from
your
supplier)
for
safe
and
efficient,
recommended
pressure
settings
on
regulators.
Check
for leaks
on
first
pressurization
and
regularly
there-after.
Brush
with
soap
solution
(capfull
of
Ivory Liq
uid*
or
equivalent
per
gallon
of
water).
Bubbles indicate
leak.
Clean
off
soapy
water
after
test;
dried
soap
is
com
bustible.
E.
User
ResponsibilIties
Remove
leaky
or
defective
equipment
from
service
im
mediately
for
repair.
See
User
Responsibility
statement
in
equipment
manual.
F.
Leaving Equipment
Unattended
Close
gas
supply
at
source
and drain
gas.
G.
Rope
Staging-Support
Rope
staging-support
should
not
be used for
welding
or
cutting operation;
rope
may
burn.
Trademark
of
Proctor & Gamble.
OM.112 875
Page
3

1-3.
ARC
WELDING
Comply
with
precautions
in
1-1,
1-2,
and
this
section.
Arc
Welding,
properly
done,
is
a
safe
process,
but
a
careless
operator
invites
trouble. The
equipment
carries
high
currents
at
significant
voltages.
The
arc
is
very
bright
and
hot.
Sparks
fly,
fumes
rise,
ultraviolet
and
in
traredenergy
radiates,
weldments
are
hot,
and
com
pressed
gases may
be used.
The
wise
operator
avoids
unnecessary
risks
and
protects
himself
and others
from
accidents.
Precautions
are
described
here
and in
stan
dards
referenced
in
index.
A.
Burn
Protection
Comply
with
precautions
in 1-2.
The
welding
arc
is
intense
and
visibly bright,
Its
radiation
can
damage
eyes,
penetrate lightweight clothing,
reflect
from
light-colored
surfaces,
and burn
the
skin
and
eyes.
Skin
burns
resemble
acute
sunburn,
those
from
gas-
shielded
arcs
are
more
severe
and
painful.
DONT GET
BURNED;
COM
PLY WITH
PRECAUTIONS.
1.
Protective
Clothing
Wear
long-sleeve clothing (particularly
for
gas-shielded
arc)
in
addition
to
gloves,
hat,
and
shoes
(1-2A).
As
nec
essary,
use
additional
protective
clothing
such
as
leather
jacket
or
sleeves,
flame-proof
apron,
and
fire-resistant
leggings.
Avoid
outer
garments
of
untreated
cotton.
Bare
skin
protection.
Wear
dark,
substantial
clothing.
Button
collar
to
protect
chest and
neck
and
button
pock
ets
to
prevent
entry
of
sparks.
2.
Eye
and
Head Protection
Protect
eyes
from
exposure
to
arc.
NEVER
look
at
an
electric
arc
without
protection.
Welding
helmet
or
shield
containing
a
filter
plate
shade
no.
12
or
denser
must
be
used
when
welding.
Place
over
face
before
striking
arc.
Protect
filter
plate
with
a
clear
cover
plate.
Cracked
or
broken helmet
or
shield
should
NOT
be
worn;
radiation
can
pass
through
to
cause
burns.
Cracked, broken,
or
loose
filter
plates
must
be
replaced
IMMEDIATELY.
Replace
clear
cover
plate
when
broken,
pitted,
or
spattered.
Flash
goggles
with
side shields MUST
be
worn
underthe
heitnet
to
give
some
protection
to
the
eyes
should
the
helmet
not
be
lowered
over
the
face
before
an arc
is
struck.
Looking
at
an arc
momentarily
with
unprotected
eyes (particularly
a
high intensity gas-shielded
arc)
can
cause
a
retinal
bum that
may
leave
a
permanent
dark
area
in
the field of
vision.
3.
Protection
of
Nearby
Personnel
Enclosed
welding
area.
For
production
welding,
a
sepa
rate
room or
enclosed
bay
is
best.
In
open
areas,
sur
round the
operation
with
low-reflective,
non-combusti
ble
screens
or
panels.
Allow for
free
air
circulation,
par
ticularly
at
floor
level.
.Viewirig
the
weld.
PrOvide face shields
for
all
persons
who
will
be
looking
di
rectly.
at
the
weld.
Others
working
in
area.
See
that all
persons
are
wearing
flash
goggles.
Before
starting
to
weld,
make
sure
that
screen
flaps
or
bay
doors
are
closed.
B.
Toxic
Fume PreventIon
Comply
with
precautions
in
1-2B.
Generator
engine
exhaust
must
be
vented
to
the
outside
air.
Carbon
monoxide
can
kill.
C.
Fire and
Explosion
Prevention
Comply
with
precautions
in
1
-2C.
Equipments
rated
capacity.
Do not
overload
arc
welding
equipment.
It
may
overheat
cables and
cause
a
fire.
Loose
cable
connections
may
overheat
or
flash and
cause
a
tire.
Never strike
an
arc
on
a
cylinder
or
other
pressure
ves
sel.
It
creates
a
brittle
area
that
can
cause
a
violent
rup
ture
or
lead
to
such
a
rupture
under
rough handling.
D.
Compressed
Gas
Equipment
Comply
with
precautions
in
1 -2D.
E.
Shock Prevention
Exposed
hot
conductors
or
other bare metal
in
the weld
ing
circuit,
or
in
ungrounded,
electrically-HOT
equip
ment
can
fatally
shock
a
person
whose
body
becomes
a
conductor.
DO
NOT
STAND, SIT,
LIE,
LEAN
ON,
OR
TOUCH
a
wet
surface
when
welding,
without suitable
protection.
To
protect
against
shock:
Wear
dry
insulating
gloves
and
body
protection.
Keep
body
and
clothing
dry.
Neverwork
in
damp
area
without
adequate
insulation
against
electrical
shock.
Stay
on
a
dry
duckboard,
or
rubber
mat
when
dampness
or
sweat
can
not
be
avoided.
Sweat,
sea
water,
or
moisture
be
tween
body
and
an
electrically
HOT
part
or
grounded
metal
reduces
the
electrical
resistance,
and
could
en
able
dangerous
and
possibly
lethal
currents
to
flow
through
the
body.
A
voltage
will
exist
between
the electrode
and
any
con
ducting object
in
the
work
circuit.
Examples
of
Conduct
ing
objects
include,
but
are
not
limited
to,
buildings,
elec
trical
tools,
work
benches,
welding
power
source
cases,
workpieces,
etc.
Never
touch
the electrode and
any
metal
object
unless
the
welding
power
source
Is of
f.
1.
Grounding
the
Equipment
Arc
welding
equipment
must
be
grounded
according
to
the
National
Electrical
Code,
and
the
work
must
be
grounded
according
to
ANSI Z49.1
Safety
In
Welding
And
Cutting.
When
installing,
connect
the
frames
of
each
unit
such
as
welding
power
source,
control,
worktable,
and
water
ci
r
culatorto
the
building
ground.
Conductors
must
be
ade
quate
to
carry
ground
currents
safely.
Equipment
made
OM-112
875
Page
4

electrically
HOTtiy
stray
current
may
shock,
possibly
fa
tally.
Do NOT
GROUND
to
electrical
conduit,
orto
a
pipe
carrying
ANY
gas
or
flammable
liquid
such
as
oil
or
fuel.
Three-phase
connection.
Check
phase requirements
of
equipment
before
installing.
If
only
3-phase
power
is
available,
connect
single-phase equipment
to
only
two
wires of the
3-phase
line. Do
NOT
connect
the
equip
ment
ground
lead
to
the
third
(live)
wire,
or
the
equip
ment
will
become
electncally
HOT-a
dangerous
condi
tion
that
can
shock,
possibly fatally.
Before
welding,
check
ground
for
continuity.
Be
sure
conductors
are
touching
bare metal of
equipment
frames
at
connections.
If
a
line
cord
with
a
ground
lead
is
provided
with
the
equipment
for connection
to
a
switchbox,
connect
the
ground
lead
to
the
grounded
switchbox.
If
a
three-prong
plug
is added for
connection
to
a
grounded
mating
re
ceptacle,
the
ground
lead
must
be
connected
to
the
ground
prong
only.
If
the line cord
comes
with
a
three-
prong
plug,
connect to
a
grounded mating
receptacle.
Never
remove
the
ground
prong
from
a
plug,
or use a
plug
with
a
broken off
ground
prong.
2.
Electrode
Holders
Fully
insulated electrode holders should be
used. Do
NOT
use
holders with
protruding
screws.
3.
Connectors
Fully
insulated
lock-type
connectors
should
be
used
to
join welding
cable
lengths.
4.
Cables
Frequently
inspect
cables
forwear,
cracks
and
damage.
IMMEDIATELY
REPLACE
those with
excessively
worn
or
damaged
insulation
to
avoid
possibly-lethal
shock
from
bared cable.
Cables
with
damaged
areas
may
be
taped
to
give
resistance
equivalent
to
original
cable.
Keep
cable
dry,
free
of oil and
grease,
and
protected
from
hot metal
and
sparks.
5.
Terminals
And
Other
Exposed
Parts
Terminals
and other
exposed
parts
of
electrical
units
should
have
insulating
covers
secured
before
operation.
6.
Electrode
a.
Equipment
with
output
on/ott
control
(contactor)
Welding
power
sources
for
use
with
the
gas
metal
arc
welding (GMAW),
gas
tungsten
arc
welding
(GTAW)
and
similar
processes
nor
mally
are
equipped
with
devices
that
permit
on
off
control of
the
welding
power
output.
When
so
equipped
the
electrode
wire
becomes
electri
cally
HOT
when the
power
source
switch
is
ON
and
the
welding
gun
switch
is
closed. Never
touch the
electrode
wire
or
any
conducting
ob
ject
in
contact
with the
electrode
circuit
unless
the
welding
power
source
is
off.
b.
Equipment
without
output
on/oft
control
(no
contactor)
-
Welding
power
sources
used with
shielded
metal
arc
welding
(SMAW)
and
similar
proc
esses
may
not
be
eq~uipped
with
welding
power
output
on-off
control
devices.
With
such
equip
ment
the electrode is
electrically
HOT
when
the
power
switch is
turned
ON.
Never
touch
the
electrode
unless
the
welding
power
source
is
off.
7.
Safety
Devices
Safety
devices such
as
interlocks
and circuit breakers
should
not
be
disconnected
or
shunted
out.
Before
installation,
inspection,
or
service,
of
equipment,
shut
OFF
all
power
and
remove
line fuses
(or
lock
or
red-
tag switches)
to
prevent
accidental
turning
ON
of
power.
Disconnect all cables
from
welding
power
source,
and
pull
all
115
volts
line-cord
plugs.
Do
not
open power
circuit
or
change
polarity
while
weld
ing.
If,
in
an
emergency,
it
must
be
disconnected,
guard
against
shock
bums,
or
flash
from
switch
arcing.
Leaving equipment
unattended.
Always
shut
OFF
and
disconnect all
power
to
equipment.
Power
disconnect
switch
must
be
available
near
the
welding
power
source.
F.
ProtectIon
For Wearers of Electronic
Life
Sup
port
Devices
(Pacemakers)
Magnetic
fields
from
high
currents
can
affect
pacemaker
operation.
Persons
wearing
electronic life
support
equipment (pacemaker)
should consult
with their
doctor
before
going
near
arc
welding, gouging,
or
spot
welding
operations.
14.
STANDARDS
BOOKLET INDEX
For
more
information,
refertothefollowing
standards
or
their
latest
revisions and
comply
as
applicable:
1.
ANSI
Standard
Z49.1,
SAFETY
IN
WELDING
AND
CUTTING
obtainable
from the American
Welding
Society,
550
N.W.
LeJeune
Rd, Miami,
FL
33126.
2.
NIOSH,
SAFETY
AND HEALTH
IN
ARC
WELD
ING
AND
GAS
WELDING
AND
CUTTING
ob
tainable
from the
Superintendent
of
Documents,
U.S. Government
Printing
Office,
Washington,
D.C.
20402.
3.
OSHA,
SAFETY
AND HEALTH
STANDARDS,
29CFR
1910,
obtainable
from
the
Superinten
dent of
Documents,
U.S. Government
Printing
Office,
Washington,
D.C.
20402.
4. ANSI Standard
Z87.1,
SAFE
PRACTICES FOR
OCCUPATION
AND
EDUCATIONAL
EYE AND
FACE PROTECTION
obtainable from the
Ameri
can
National
Standards
Institute,
1430 Broad
way,
New
York,
NY
10018.
5.
ANSI
Standard
Z41
.1,
STANDARD
FOR
MENS
SAFETY-TOE
FOOTWEAR
obtainable
from
the
American
National
Standards
Institute,
1430
Broadway,
New
York,
NY
10018.
OM-112
875
Pa9e
5

6.
ANSI
St~ndard
Z49.2,
FIRE
PREVENTION
IN
THE
USE
OF
CUTTING
AND
WELDING
PROC
ESSES
obtainable from the
American
National
Standards
Institute,
1430
Broadway,
New
York,
NV
10018.
7.
AWS Standard
A6.0,
WELDING AND
CUTTING
~CONTAlNERS
WHICH
HAVE
HELD COMBUS
TIBLES
obtainable
from the
American
Welding
Society,
550
N.W.
LeJeune
Rd,
Miami,
FL
33126.
8.
NFPA
Standard
51,
OXYGEN-FUEL
GAS SYS
TEMS
FOR
WELDING,
CUTTING,
AND
ALLIED
PROCESSES
obtainable from
the
National Fire
Protection
Association,
Batterymarch
Park,
Quincy,
MA
02269.
9.
NFPA
Standard
70,
NATIONAL ELECTRICAL
CODE
obtainable
from
the
National Fire
Protec
tion
Association,
Batterymarch
Park,
Quincy,
MA
02269.
10.
NFPA
Standard
51
B,
CUTTING
AND
WELDING
PROCESSES
obtainable
from
the
National
Fire
Protection
Association,
Batterymarch
Park,
Quincy,
MA
02269.
11. CGA
Pamphlet
,
HANDLING
OF COM
PRESSED GASES
IN
CYLINDERS
obtainable
~rorn
the
Compressed
Gas
Association,
1235 Jef
ferson
Davis
Highway,
Suite
501,
Arlington,
VA
22202.
12.
CSA
Standard
W117.2,
CODE
FOR SAFETY
IN
WELDING
AND
CUTTING
obtainable from
the
Canadian
Standards
Association,
Standards
Sales,
178 Rexdale
Boulevard,
Rexdale,
Ontario,
Canada
M9W
1
R3.
13.
NWSA
booklet,
WELDING
SAFETY
BIBLIOG
RAPHY
obtainable
from
the
National
Welding
Supply
Association,
1900
Arch
Street,
Philadel
phia,
PA
19103.
14.
American
Welding
Society
Standard
AWSF4.1,
RECOMMENDED
SAFE PRACTICES
FOR
THE
PREPARATION FOR
WELDING
AND
CUTTING
OF
CONTAINERS
AND
PIPING
THAT
HAVE
HELD
HAZARDOUS
SUBSTANCES,
obtainable
from the American
Welding
Society,
550
N.W.
LeJeune
Ad,
Miami,
FL
33126.
15. ANSI
Standard
Z88.2,
PRACTICE
FOR
RESPI
RATORY
PROTECTION,
obtainable
from
the
American
National
Standards
Institute,
1430
Broadway,
New
York,
NY
10018.
SECTION
2-
SAFETY
PRECAUTIONS
AND
SIGNAL
WORDS
2-1.
GENERAL
INFORMATION
AND
SAFETY
A.
General
Information
presented
in
this
manual
and
on
various
la
bels,
tags,
and
plates
on
the
unit
pertains
to
equipment
design,
installation,
operation,
maintenance,
and
troubleshooting
which
should be
read,
understood,
and
followed
for the safe and
effective
use
of
this
equipment.
The
nameplate
of
this
unit
uses
international
symbols
for
labeling
the front
panel
controls.
The
symbols
also
ap
pear
at
the
appropriate
section
in
the
text.
B.
Safety
The
installation,
operation,
maintenance,
and
trouble
shooting
of
arc
welding
equipment
requires practices
and
procedures
which
ensure
personal
safety
and the
safety
of others.
Therefore,
this
equipment
is
to
be
in
stalled,
operated,
and
maintained
only by qualified
per
Sons
ifl
accordance
with
this
manual
and
all
applicable
codes such
as,
but
not
limited
to,
those listed
at
the
end
of Section 1

Safety
Rules
For
Operation
Of
Arc
Weld
ing
Power
Source.
2-2.
SAFETY
ALERT
SYMBOL
AND
SIGNAL
WORDS
The
following
safety
alert
symbol
and
signal
words
are
used
throughout
this
manual
to
call
attention
to
and iden
tify
different
levels
of
hazard
and
special
instructions.
a
This
safety
alert
symbol
is
used
with
the
signal
words
WARNING
and
CAUTION
to
call
atten
tion
to
the
safety
statements.
a
WARNING
statements
identify procedures
or
practices
which
must
be
followed
to
avoid
seri
ous
personal injury
or
loss
of life.
a
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
equip-
merit.
OM-112
875
Page
6

SECTION
3-
SPECIFICATIONS
Table
3-1.
SpecificatIons
Welding
Power
Source
Model
Rated
Weld
Output
Max.
Open.
Circuit
Voitage
input
At
Rated Load
Single-Phase

KW
Control
Circuit
Voltage
At Gun
Electrode
Wire
Feed
Speed
Electrode
Wire
Diameter
Capability
Weight
Amperes
At
 
11SV 230V
)(VA
Net
Ship
MW
4110
90
Amperes
@
18
Volts DC
20%DutyCycle
30
20

10
20
3

2.2

24
Volts
DC
70-400
ipm
(1.8-10.2mpm)
.023
in.
(0.6mm)
88
lbs.
(40kg)
95 lbs.
(43kg)
MW
4230
l20Amperos
@
21
Volts
DC
30%
Duty Cycle
32

4.7 3.9
47-690
ipm
(1.2-17.5mpm)
.023 thru .035
in.
(0.6thruo.9mm)
94
lbs.
(43kg)
101 lbs.
(46kg)
MWG-160 Gun
Ampere Rating
With
CO
60%
Duty
C~cie
Wire
DIameter
Cabie
Length
Cooling
Metho
l6oAmpores
.023
in.
(0.6
mm)
lOft.
(3.0
m)
Air
TB-
1
12 943-A
15
In.
(381
mm)
Figure
3-1.
Overall
Dimensions
19
In.
(483
mm)
OM-112
875
Pago
7

A.
Welding
Power
Source
(Chart
3-2)
The MW
4110
is
rated
at
20
percent
duty
cycle;
there
fore,
the unit
can
be
operated
at
rated
load for
two
con
secutive
minutes
out
of
ten,
but
it
must
idle
for the
re
maining
eight
minutes
to
allow
proper
cooling.
The MW
4230 is rated
at
30
percent
duty
cycle;
there
fore,
the unit
can
be
operated
at
rated
load
for
three
con
secutive
minutes,
but
it
must
idle
forthe
remaining
seven
minutes to allow
proper
cooling.
B.
Welding
Gun
The
duty cycle
of
a
welding
gun
is the
percentage
of
a
ten
minute
period
that
a
gun
can
be
operated
at
a
given
load.
This
gun
is rated
at
60%
duty
cycle using
CO2
shielding
gas.
This
means
that the
gun
can
be
operated
six
min
utes out
of
every
ten
with
the
CO2
shielding
gas.
The
re
maining
four minutes the
gun
should
be
idle
to
permit
proper
cooling.
~Referio
the
Duty
Cycle
Charts
(Chart
3-2)
to
determine
the
output
of
the
welding
power
source
at
various
duty
cycles.
IMPORTANT:
Decreasing
welding
amperes
increases
duty
cycle.
a
CAUTION: EXCEEDING
DUTY CYCLE
RATINGS
will
damage
welding
power
source.

Do not
exceed
indicated
duty
cycles.
Chart
3-2.
Duty
Cycle
A.
MW
4110 Models
I
5C
125
100
75
50
2~
0

10 15
B. MW
4230 Models
3-1.
VOLT-Aii~lPERE
CURV~S
(Chart
3-1)
(3*
RATED
OUTPUT
The
volt-ampere
curves
show
the
minimum
and maxi
mum
voltage
and
amperage
output
capabilities
of the
unit ft~om
the minimum
and
maximum
settings
of
the
FINE
TUNING/WIRE SPEED
control.
Chart
3-1.
Volt-Ampere
Curves
A.
MW
4110
Models
50
40
~,30
I-
-J
0
>
~20
0
I0
0
B.
MW
4230
Models
40
30
20
Ca
a
10
0
3-2.
DUTY
CYCLE
(I)
w
Lii
0~
x
a
d
~
S8.l10
683
20
25
30 40
50607080
100
i~
DUTY CYCLE
SA109
428
0
60
100
160
200
250
D.C.
A~P~ES
SB-124
625
206
  -



-
160
100
90
90
70
60
.~
~
%
I
.6
%
40
wry cye.E
x
90 100
S8.124
624
OM-112
875
Page
8

CAUTION:
EXCEEDING
THE
RATED
AM
PERAGE
WITH
CO~
OR
FAILING TO
RE
DUCE
THE
WELDING
AMPERAGE
OR
DUTY
CYCLE WHEN
USING
A
MIXED
SHIELDING
GAS
can
result
In
damage
to
the
gun.

Do
not
exceed
rated
amperage
when
using
Co2.

Reduce
duty cycle
when
using
mixed shield
ing
gases
such
as
carbon
dioxide
and
argon.
3-3.
DESCRIPTION
The
MW
4110
is
a
single-phase,
constant
voltage,
dc
arc
welding
power
source
and wire
feed
system
designed
for
Gas
Metal
Arc
Welding (GMAW)
using
a
MWG-1
60
gun
and .023
in.
(0.6
mm)
welding
wire.
Rated
weld
out
put
is
90
amperes,
18 volts
dc,
at
20%
duty
cycle.
The
MW
4230 is
a
single-phase,
constant
voltage,
dc
arc
welding
power
source
and wire
feed
system
for
Gas
Met
al
Arc
Welding
(GMAW)
using
a
MWG-1
60
gun
and
.023
through
.035
in.
(0.6
through
0.9
mm)
welding
wire.
Rated
weld
output
is 120
amperes,
21
volts
dc,
at
30%
duty
cycle.
All
units
are
protected
against
short
circuit
overload
(contact
tube
shorting
to
work)
and
overheating.
If
either
condition
occurs,
the unit
automatically
shuts
down.
3-4.
SUPPLIED EQUIPMENT
(FIgure
3-2)
Figure
3-2.
Supplied
Equipment
Equipment
supplied
with
the
welding
power
source
and
requiring
customer
installation
or
assembly
is
listed
be
low:
1.
Welding
gun
with
1/2
in.
(13
mm)
seam
nozzle
and
two
contact
tubes.
2.
Work
clamp.
The
weldi~ig
power
source
is
factory
equipped
with
a
10
ft.
(3
m)
input
power
cord
and
built-in
gas
valve.
3-5.
ADDITIONAL
REQUIRED
EQUIPMENT
(Fig
ure
3-3)
Contact
yoursupplier
or see
the
yellow
pages
of
the local
telephone
book for the location
of
the
nearest
welding
supply
company
to
obtain the
necessary
equipment.
A.
Gas
Cylinder
Two
types
of
gas
are
generally
used
with
Gas
Metal
Arc
Welding
(GMAW)
of
thin
gauge
sheet steel. Carbon
dioxide
(C02)
is
the
gas
recommended for
use
with
this
welding
power
source/gun
combination.
A
mixture
of 75
percent
argon
and
25
percent
carbon
dioxide
also
gives
favorable
results.
Obtain
a
cylinderof
selected
shielding
gas.
When
welding
power
source
is installed
on
running
gear,
a
20
lb.
cylinder
is the
largest
that
can
be
used.
B.
Regulator/Flowmeter
Regulator/f
lowmeters
provide
a
constant
shielding
gas
pressure
and flow
rate
dunng
the
welding
process.
Be
cause
gases
have
different
properties,
each
regulator!
flowmeter
is
designed
to
be
used with
a
specific
gas
or
mixture
of
gases.
Regulator/flowmeters
cannot
be
changed
from
one
gas
to
another unless the
proper
adapters
are
installed.
Be
sure
to
obtain the
proper regu
lator/fiowmeter
for
the
type
of
gas
used.
C.
Gas
Hose
Measure
distance from
gas
cylinder
to
welding
power
source.
Obtain
good
quality
5/8
in.
(16
mm)
O.D.,
S.A.E.
gas
hose,
and install 5/8-18
right-hand
thread
fittings
on
both
ends of
hose.
a
Figure
3-3.
AdditIonal
Supplies
Required
OM-112
875
Page
9

D.
Spool
Of
~Jlre
Selection
of
the
correct
welding
wire
is
important
in
Gas
Metal
Arc
Welding
(GMAW).
There
are
many
types
of
wire
from
which
to
choose,
but certain
wires
are
best
suited
for
welding
thin
gauge
sheet
steel.
The American
Welding
Society
(AWS)
classification
for
GMAW
wires
is
usually
indicated
on
the label
of the
wire
spool.
Two AWS
wire
classes
recommended
are
E7OS-6
and
E7OS-3.
The
E7OS-6
provides
a
more
fluid
(wetter)
weld
puddle
and
a
flatter
bead; however,
E7OS-6
is
acceptable
for
use
with
this
welding
power
source.
Obtain
a
spool
of
se
lected
wire.
E.
Personal
Safety
Equipment
When
using
this
welding
power
source,
wear
a
welding
helmet,
fitted
with
the
proper
filter
lens,
to
protect
the
eyes
from the
welding
arc.
Also
important
is
wearing
pro
tective
clothing,
safety
glasses,
and
gloves
to
prevent
in
jury.
3-6.
OPTIONAL
EQUIPMENT
This
unit
can
be
equipped
with
two
styles
of
running
gear.
If
running
gear
was
ordered
with
the
unit,
see
run-
fling
gear
Owners
Manual
for
installation
procedures.
3-7.
CONSUMABLE
PARTS
The
following
parts
are
subject
to
wear
under normal
usage:
1. Contact
tubes
2.
Contact
tube
adapters
(170
Ampere
Model
Guns
Only)
3.
Nozzle
4.
Drive Rolls
Spare
parts
should
be
available
at
all
times.
SECTION
4
INSTALLATION
Gas
Cylinder
Valve
CO2 Cylinder
CO2
Installation
Argon
or
Argon
Mix
Cylinder
SB-109
492
Flowmeter
Cap
CO2
Washer
Fiowmeter
Regulator
Cap
Argon
Installation
Figure
4-1.
TypIcal
Regulator/Flowmeter
Installation
OM-112
875
Page
10

4-1.
SITE
SELECTION
(FIgure
3-1)
Select
an
installation
site
which
provides
the
following:
1.
Correct
input
power
supply
(see
unit
nameplate)
2.
Shielding
gas
supply
3...
Adequate
ventilation
and fresh air
supply
4.
No
flammables
5.
A
clean and
dry
area
6.
Proper
temperature
that
avoids
extremes
of heat
or
cold
7.
Proper
airflow
around unit
8.
Adequate
space
for
opening
side
access
doors
for
installation, maintenance,
and
repair
func
tions.
Base
mounting
holes
provide
the
capability
to
install
and
secure
the unit
on a
running
gear
or
in
a
permanent
loca
tion.
a
WARNING:
FIRE
OR
EXPLOSION
can
result
from
placing
unit
on or
over
combustible
surfaces;
RESTRICTED
AIRFLOW
can
cause
overheating
and
possible
damage
to
Internal
parts.

Do
not
locate unit
over
combustible
surfaces.

Maintain
at
least
18
inches
(457
mm)
of
unrestricted
space
on
a/i
sides
of
unit,
and
keep
underside
free of
obstructions.

Do
not
place
any
filtering
device
over
the
in
take air
passages
that
provide
airflow
for
coo/mg
this unit.
Warranty
is
void
if
any
type
of
filtering
device
is
used
at
intake
air
passages.
4-2.
SHIELDING
GAS
INSTALLATION
a
WARNING:
PRESSURIZED
CYLINDERS
can
rupture
causing
serious
personal
Injury
and
loss
of
life;
FALLING
CYLINDERS
can
cause
serious
Injury
and
equipment
damage.

Keep
cylinders
away
from
welding
or
other
electrical
circuits.

Never allow
a
welding
electrode
to
touch
any
cylinder.

Always
fasten
cylinder
securely
to
running
gearbracket,
a
wall,
orotherstationary
support.
A.
Gas
Cylinder
(Customer
Supplied)
(Figure
4-1)
Chain
the
cylinder
to
a
wall
or
other
stationary
support
to
prevent
the
cylinderfrom
failing
over
and
breaking
oft
the
valve.
If
optional
running
gear
is
used,
secure
gas
cylin
der
to
running
gear
with
supplied
chain.
B.
Reguttor/Flowm.eter
(Customer
Supplied)
(Fig.
-
ure4-1)
1.
With the
cylinder
securely
installed,
remove
the
cylinder
cap,
stand
to
one
side of
cylinder
valve,
and
open
valve
slightly.
When
gas
flows
from
cyl
inder,
close
valve.
This
procedure
blows
Out
dust
or
dirt that
may
have
accumulated
around
the
valve
seat.
2.
The
regulator/f
Iowmeter
must
be
properly
equipped
with
a
stem,
nut
connectors,
and
gasket
for
use
with
either
CO2
cylinders
or
inert
gas
type
cylinders.
IMPORTANT:
A
gasket
should
be installed
to
prevent
leaks.
Do
not
use
lubricants
or
sea/mg
agents.
3. Install
gas
regulator/flowmeter
onto
gas
cylinder
valve;
keep
the face of the
regulator/flowmeter
gauge
in
vertical
position,
and
tighten
stem nut
securely
to
gas
cylinder
valve.
4.
A
shielding
gas
output
fitting
is
provided
at
the
rear
of
the
welding
power
source
for
making
gas
connections.
Attach
one
end
of the
gas
hose
to
this
output
fitting.
Attach
other
end of
the
gas
hose
to
the
regulator/f
Iowmeter.
4-3.
WORK
CLAMP
INSTALLATION
(Figure
4-2)
A
10 ft.
(3
m)
work
cable
with
lug
extends
out
of
the front
panel.
Install work
clamp
onto
the
work
cable
as
follows:
a
WARNING: ELECTRIC SHOCK
can
kill.

Do
not
touch
live
electrical
parts.

Shutdown
welding
powersource,
anddiscon
nect
input
power employing
lockout/tagging
procedures
before
installing
work
clamp.
Lockout/tagging
procedures
consist of
removing
input
power
plug
from
receptacle,
padlocking
line disconnect
switch
in
open
position,
remov
ing
fuses
from
fuse
box,
or
shutting
off
and red
tag9ing
circuit
breaker
or
other
disconnecting
device.
Step
3
S.0250
Step
6
Step
2
Step
4
Steps
1
and 5
Figure
4.2.
Work
Clamp
Installation
OM-112
875
Page
11

1.
Slide
one
piece
of
su~pIied
insulating
sleeve
onto
work
cable.
2.
Place
work
cable
inside
the
handle
of
the work
clamp
with
the
flattest
inner
surface.
3.
Align
the
smaller
hole
in
the
work
clamp
handle
with
the
hole
in
the
work
cable terminal
lug.
Se
cure
the terminal
lug
to
the
work
clamp
with
the
supplied
nut
and
bolt.
4.
Bend
the
tabs
on
the end
of
the
work
clamp
around
the
work
cable.
5.
Slide
insulating
sleeve
on
work
cable
over
work
clamp
handle.
6.
Slide
remaining
insulating
sleeve
over
other
work
clamp
handle.
4-4.
GUN
POLARITY
SELECTION
PROCEDURE
(FIgure
4-3)
a
WARNING:
ELECTRIC
SHOCK
can
kIll.

Do
not
touch
live
electrical
parts.

Shut
down
welding
powersource,
and
discon
nect
input
power
employing
lockout/tagging
procedures
before
inspect
ing
or
changing
connections.
Lockout/taggingprocedures
consist
of
removing
input
power
plug
from
receptacle,
padlocking
line disconnect switch
in
open
position,
remov
ing
fuses
from
fuse
box,
or
shutting
off and red
tagging
circuit
breaker
or
other
disconnecting
device.
The
welding
power
source
has
jumper
links
that
allow
the
userto
select
the
polarity
of the
unit.
The
jumper
links
can
be
positioned
for
Reverse
Polarity
(DCEP)
or
Straight
Polarity
(OCEN)
welding
(see
Figure
4-3).
The
unit
was
shipped
with the
links
positioned
for
Re
verse
Polarity
(DCEP)
welding
using
solid
steel
wire
with
the
Gas
Metal Arc
Welding
(GMAW)
process.
If
using
flux
cored wire
(without
adding
a
shielding
gas)
and
the
Flux
Cored
Arc
Welding
(FCAW)
process,
position
links
for
Straight
Polarity (DCEN).
Straight
Polarity (DCEN)
can
also
be
used
for
welding
with
solid
wire
on
very
thin
metal.
The
jumper
links
are
located
behind
the
access
door.
The
polarity
changeover
label
(Figure
4-3)
is
located
next to
the
polarity
changeover
board
on
the
center
baffle
of
the unit.
If
it
is
necessary
to
change
jumper
link
positions,
proceed
as
follows:
1.
Open
left side
access
door.
2.
Loosen
hardware
securing
jumper
links
to
polar
ity
changeover
board.
3.
Reposition
jumperlinks
as
necessary,
andtighten
jumper
link
securing
hardware.
4.
Close
and
secure access
door.
REVERSE
Steel
Or
POLARITY
For
Solid
Aluminum
(GMAW)
Wires
DCEP
J
process)
Gun/Feeder Connector
Securing
Knob
FIgure
4-3.
Gun
Polarity
Selection
P
STRAIGHT
I
POLARITY
For
Flux
Cored
Wires,~
(
)
(FCAW
process)
L
DCEN
Polarity
Changeover
Label
Hub
GUN
POLARITY
CHANGEOVER
I
S-116
599
Polarity Changeover
Board
Gun/Feeder
Connector
OM-112
875
Page
12

4-5.
WELDING
GUN
INSTALLATION
(Figures
4.3
And
4-4)
a
WARNING:
ELECTRIC SHOCK
can
kill.

Do
not
touch
live electrical
parts.

Shutdown
welding
powersource,
and
discon
nect
input
power
employing
lockout/tagging
procedures
before
inspecting
or
installing.
Lockout/tagging
procedures
consist
of
removing
input
power
plug
from
receptacle,
padlocking
line
disconnect
switch
in
open
position,
remov
ing
fuses from
fuse
box,
or
shutting
ott
and
red-
tagging
circuit
breaker
or
other
disconnecting
device.
A.
Gun/Feeder
Connector Installation
(Figures
4-3
And
4-4)
IMPORTANT:
The
outlet
guide
is
provided
as
part
of the
gun
assembly.
1.
Open
access
door.
2.
Loosen
the
gun/feeder
connector
securing
knob.
IMPORTANT:
Wire
guides
should be installed
so
that
the
tip
of the
guide
is
as
close
to
the
drive rolls
as
possi
ble
without
touching.
3.
Insert
gun/feeder
connector
through
access
hole
in
front
panel
and into drive
assembly
until
gun/fe
eder
connector
is flush
against
drive
assembly.
4.
Tighten
the
gun/feeder
connector
securing
knob.
5.
Close
and
secure access
door.
B.
Gun Switch
Connection
(Figure
5-1)
The
WELDING GUN
receptacle
is
provided
for
making
switch
control
connections.
Align
the
keys
on
the
gun
switch
connector
with
the
keyways
in
the
WELDING
GUN
receptacle,
insert
the
connector,
and
rotate
collar
fully
clckwise.
4-6.
WELDING
WIRE
SPOOL
INSTALLATION
(Figure
4-4)
1.
Open
left side door.
2.
Remove
retaining
pin
from
hub.
3.
Slide
spool
of wire
onto
hub
so
that
wire feeds
off
bottom
of
spool.
Do not
loosen wire from
spool.
4.
Rotate
spool
until hole
in
spool
aligns
with
pin
in
hub.
Slide
spool
onto
hub until
it
seats
against
back
flange
of hub.
5.
Reinstall
retaining
pin
onto
hub
in
a
position
which
prevents
wire
spool
from
moving
in
or
out.
6.
Close
and
secure
access
door.
4-7.
ELECTRICAL
INPUT
CONNECTIONS
a
WARNING: ELECTRIC SHOCK
can
kill.

Do
not
touch live electrical
parts.

Shutdown
welding
power
source,
and
discon
nect
input
power
employing
lockout/tagging
procedures
before
inspecting
or
installing.
Lockout/tagging procedures
consist
of
removing
input
power
plug
from
receptacle,
padlocking
line disconnect switch
in
open
position,
remov
ing
fuses
from
fuse
box,
or
shutting
ott
and red-
tagging
circuit
breaker
or
other
disconnecting
device.
A.
Electrical
Input Requirements
The
National
Electrical
Code
(NEC)
(Article
630B.,
1987
Edition)
provides
standards
for
amperage
handling
ca
pability
of
supply
conductors
based
on
the
duty
cycle
of
the
welding
power
source.
SA-109 356-s
Hub Pin
Pressure
Roll
Assembly
(Shown
in
Open
Position)
Front Panel
Gun
Wire
Spool
I
Retaining
Pin
Wire inlet
Guide
FIgure
4-4.
WeldIng
Gun
And Wire
Spool
installation
OM-112
875
Page
13

The
MW
4110
models
have
a
20%
duty
cycle (2
minutes
of
every
10
minutes
can
be
used
for
welding);
therefore,
the
supplied
cord
and
attached
plug
comply
with
NEC
standards
for
20%
duty cycle.
Be
sure
that
the
building
supply
and
receptacle
comply
with
NEC
standards
and
any
additional
state
and
local
codes.
The
MW
4230
(230
Volts
only)
models have
a
30%
duty
cycle
(3
minutes
of
every
10
minutes
can
be
used for
welding);
therefore,
the
supplied
cord
and
ring
terminals
comply
with
NEC
standards
for
30%
duty
cycle.
IMPORTANT:
The
supply
wiring
for the
welding
power
source must
be
capable
of
handling
a
15
ampere
load for
the
MW4
110
models,
anda 20
ampere
load for
the
MW
4230
models. The
welding
power
source must
be the
only
load
connected
to
the
supply
circuit.
Poor
unit
per
formance
or
frequently
opening
line
fuses
or
circuit
breakers
can
result from
an
inadequate
or
improper
supply.
B.
input
Conductor
ConnectIons
For
MW
4110
Models
MW
4110
models
are
equipped
with
a
cord
and three-
prong
polarized
plug.
Check
nameplate
for
input
voltage
requirement,
and
connect
the
plug
to
.a
properly
grounded
and
protected
(fuses
or
circuit
breakers)
115
VAC
receptacle
capable
of
handling
15
amperes.
C~
Input
Conductor
Connections
For
MW
4230
Models
(Table
4-1
And
Figure
4-4)
a
WARNING:
ELECTRIC
SHOCK
can
kill.

Do
not
touch
live
electrical
parts.

Install
a
fusible line
disconnect
switch
in
the
input
Circuit
to the
welding
power
source.

Read
and
follow
safety
information
at
begin
ning
of
entire
Section
4-7
before
proceeding.
The
line
disconnect
switch
provides
a
safe
and
convenient
means
to
completely
remove
all
electrical
power
from
the
welding
power
source
whenever
it
is
necessary
to
inspect
or
service
the
unit.
Table
4-1
provides
guidelines
for
selecting
the
proper
size
line
fuses.
Table
4-1.
Line
Disconnect Or
Supply
Circuit
Fuse
Size
Model
Fuse
Size
In
Amperes*
MW411O
30
MW
4230
30
*Fuse
size is
based
on
not
more
than
200
per
cent
of
the
rated
input
amperage
of
the
welding
power
source
(Article
630
of
NEC).
s-oogv~-ea
~a
WARNING:
ELECTRIC
SHOCK
can
kill.

Do
not
touch live,
electrical
parts.

Do
not
connect
an
input
conductor
to
the
ground
terminal
in
the line
disconnect
device.

Do
not
connect
the
ground
conductor
to
an
input
line
terminal.
Incorrect
input
connections
can
result
in
an
electrically
energized welding
power
source
chassis. The
ground
terminal
is
connected
to
the
welding
power
source
chassis
and is for
grounding
purposes
only.
Models
requiring
230
volts
input
have
prewired
power
cables
with
three
conductors
and
ring
terminals. Check
the
nameplate
for
input
voltage
requirement,
and
con
nect
the
conductors
to
a
properly
grounded
and
pro
tected line
disconnect
device
capable
of
handling
230
VAC
at
20
amperes
(see
Figure
4-5).
The
black
and
white
conductors
must
be
connected
to
the line
terrrii
nals,
and
the
green
conductor
must
be
connected
to
a
proper
ground.
Use
a
grounding
method
that is
accept
able
to
the
local
electrical
inspection
authority.
Ground
Conductor
Figure
4.5.
Power Cable
Connections
(230
Volt
Models
Only)
4-8.
WELDING
WIRE
INSTALLATION
A.
Threading
Welding
WIre
(Figure
4-4)
a
WARNING:
ELECTRIC
SHOCK
can
kill;
MOVING
PARTS
can cause
serious
injury.

Do
not
touch
live electrical
parts.

Keep
away
from
moving
parts.

Do
not
energize
welding
powersource
until
in
structed
to
do
so.
The
welding
wire and all metal
parts
in
contact
with it
are
energized
while
welding.
Input
Power
From
Welding
Source
(230
Volt
Models
Only)
S9.124
654.~
OM-112
875
Pago
14

WELDING
WIRE
can
cause
puncture
dnv~e
rolipressurØ
just
tightly
enough
to
prevent
wounds;
HOT SURFACES
can cause severe
the
wire from
slipping
on
or
against
drive
roll
dur
burns.
ing
operation.

Do
not
press gun
trigger
until instructed
to
do
so
CAUTION:
EXCESSIVE
DRIVE
ROLL
TEN.
SION
can
damage
equipment
and
cause

Do
not
point
gun
toward
any
part
of
the
body,
poor
wire
feedIng.
any
conductive
surface,
or
other
personnel
when
threading welding
wire.

Do
not
overtighten
drive roll
pressure
adjust
ment
knob.

Allow
gun
to
cool before
touching.
10.
Lay
gun
cable
assembly
out
as
straight
and flat
as
1.
Open
and
secure
left
side
access
door.
possible.
2.
install
welding
wire
spool
according
to
Section
WARNING: ELECTRIC SHOCK
can
kill.
4.6.

Do
not
touch
live electrical
parts.
3.
Loosen
pressure
adjustment
knob,
pivot
pres-
The
welding
wire is
electrically
energized
when-
sure
adjustment
arm
free of
cover,
and
pivot
pres-
ever
the
gun
trigger
is
depressed.
sure
roll
assembly
away
until it is
in
an
open
posi-
WELDING
WIRE
can
cause
puncture
tion
(see
Figure
4-4).
wounds.
~
CAUTION: LOOSE WELDING
WIRE
can

Do
not
point
gun
toward
any
part
of the
body,
cause
Injury,
other
personnel,
or
any
conductive
surface
when
threading welding
wire.

Keep
firm
hold
on
wire
during
installation,
removal,
and
threading
operations.
11.
Energize welding
power
source.
Spooled
wire
has
a
tendency
to
unravel
rapidly
12.
Depress
and hold
the
gun
trigger
until
the wire
when loosened from the
spool.
feeds
approximately
1/4
in.
(6 mm)
out
the
gun
nozzle.
if wire
feeds
more
than
1/4
in.
out
nozzle,
4.
Unreel
and
straighten
approximately
6
in.
(152
cut
wire off
to
1/4
in.
mm)
of wire
from
wire
spool.
13.
Deenergize
welding
power
source.
5.
Cut
oft
any
wire
that
is
bent,
and
remove
any
burrs
14.
Adjust
hub
tension
according
to
Section
4-8B,
if
or
sharp edges.
necessary.
6.
Route
welding
wire into wire
inlet
guide, along
15.
Close
and
secure
left side
access
door.
drive
roll
groove,
and
into
wire
outlet
guide
in
gun
feeder/connector.
IMPORTANT:
Fora smoother
weld
start,
be
sure
weld-
7.
Pivot
pressure
roll
assembly
downward
onto
iflg
wire
extends
1/4
in.
(6
mm)
out
end of
contact
tube
drive
roll,
making
sure
that wire
is
riding
in
drive
and has
a
sharp
end.
roll
groove.
B.
Hub
Tension
Adjustment
8. Pivot
pressure
adjustment
arm
up
until the
wash-
Check
hub
tension
by
slowly pulling
the
wire
toward
the
er
on
the
adjustment
arm
is
seated
on
top
of the
drive
roll.
The
wire
should
unwind
freely,
but hub tension
cover.
should
be
sufficient
to
keep
the wire
taut
and
prevent
9.
Rotate
the
pressure
adjustment
knob
in
a
clock-
backlash
when wire
feeding
ceases.
If
adjustment
is
re
wise
direction
until the
drive
roll and
pressure
quired,
loosen
or
tighten
the hex
nut
on
the end of
the
bearing
are
tight
against
the
welding
wire.
Adjust
spindle
support
shaft
accordingly.
OM-112
875
Page
15

SECTION
5-
OPERATOR
CONTROLS
Figure
5-1.
Operator
Controls
5-1.
POWER
SWITCH
(Figure
5-1)
POWER
-e
Placing
the
POWER
switch
in
the ON
position
energizes
the
welding
power
source.
Placing
the
POWER
switch
in
the
OFF
position
shuts
down
the
welding
power
source.
5-2.
THICKNESSNOLTS
SWITCH
(Figure
5-1)
2
DO NOT
OPERATE
SWITCH
UNDER
LOAD
The
THICKNESSNOLTS
switch
provides
a
selection
of
four
welding voltages:
MW4I1O
MW4230
Model
Model
1

Very
Thin
2

Thin
20
Volts
DC
23
Volts
DC
20 Volts
DC
23
Volts
DC
3Thicker 25
Volts
DC
27
Volts DC
4
Thickest
29
Volts DC
32
Volts DC
a
CAUTION:
ARCING
can
damage
contact
surfaces.

Do
not
change
position
of
THICKNESS!
VOLTS switch
while
welding
or
under load.
Arcing
causes
the
contacts
to
become
pitted
and
eventually
inoperative.
5-3.
FINE
TUNING/WIRE
SPEED CONTROL
(Fig
ure
5-1)
WIRE
SPEED
FINE
TUNING
olo
The FINE
TUNING/WIRE
SPEED
control
provides
se
lection
of
the
speed
at
which
welding
wire
feeds
into the
weld.
Rotating
the
FINE
TUNING/WIRE
SPEED
control
clockwise
increases
wire feed
speed.
The
scale
around
the
FINE
TUNING/WIRE
SPEED
con
trol is
calibrated
in
percent
arid
does
not
indicate
the
ac
tual
wire
feed
speed.
IMPORTANT:
The
FINE
TUNING/WIRE
SPEED
con
trol
may
be
adjusted
while
welding.
5-4.
WELDING
GUN RECEPTACLE
(Figure
5-1)
Connect
gun
switch
to
this
receptacle according
to
Sec
tiOn
4-5. When the
gun
switch Is
closed,
the
contactor
in
the
welding
power
source
energizes,
shielding
gas
flows,
and
wire
feeds.
Fine
Tuning/
Wire
Speed
Control
Power
Switch
Gun
Thicknessivoits
Switch
Gun
Switch
Receptaci.
T8-112
g43-A
OM-112 875
Page
16