January
1980
FORM:
OM-1023B
Effective
With
Style
No.
JA-2
MODEL
MMT-300A1
MMT-400A1
OWN
ERS
MANUAL
hullER
MILLER
ELECTRIC
MFG.
CO.
718
S.
BOUNDS
ST.
P.O.
Box
1079
APPLETON,
WI
54912
USA
ADDITIONAL
COPY
PRICE
30
CENTS
NWSA
CODE
NO.
4579
PRINTED
IN
U.S.A.
~~P
~
q~~p
L
LIMITED
WARRANTY
EFFECTIVE:
JUNE
1,
1979
This
warranty
supersedes
all
previous
MILLER
warranties
and
is
ex
clusive
with
no
other
guarantees
or
warranties
expressed
or
implied.
LIMITED
WARRANTY-Subject
to
the
terms
and
conditions
As
a
matter
of
general
policy
only,
Miller
may
honor
claims
)
hereof,
Miller
Electric
Mfg.
Co.
Appleton,
Wisconsin
warrants
submitted
by
the
original
user
within
the
foregoing
periods.
to
its
Distributor/Dealer
that
all
new
and unused
Equipment
(
furnished
by
Miller
is
free
from
defect
in
workmanship
and
In
the
case
of
Millers
breach
of
warranty
or
any
other
duty
material
as
of
the
time
and
place
of
delivery
by
Miller.
No
war-
with
respect
to
the
quality
of
any
goods,
the
exclusive
remedies
ranty
is
made
by
Miller
with
respect
to
engines,
trade
ac-
therefore
shall
be,
at
Millers
option
Ii)
repair
or
(2)
replacement
cessories
or
other
items
manufactured
by
others.
Such
or,
where
authorized
in
writing
by
Miller
in
appropriate
cases.
(3)
engines,
trade
accessories
and
other
items
are
sold
subject.
to
the
reasonable
cost
of
repair
or
replacement
at
an
authorized
the
warranties
of
their
respective
manufacturers,
if
any
.
All
Miller
service
station
or
(4)
payment
of
or
credit
for
the
purchase
)
engines
are
warranted
by
their
manufacturer
for
one
year
from
price
(less
reasonable
depreciation
based
upon
actual
use)
upon
date
of
original
purchase.
return
of
the
goods
at
Customers
risk
and
expense.
Upon
receipt
of
notice
of
apparent
defect
or
failure,
Miller
shall
instruct
the
clai-
f~
Except
as
specified
below,
Millers
warranty
does
not
apply
mant
on
the
warranty
claim
procedures
to
be
followed.
to
components
having
normal
useful
life
of
less
than
one
(1)
year,
such
as
spot
welder
tips,
relay
and
contactor
points,
ANY
EXPRESS
WARRANTY
NOT
PROVIDED
HEREIN
AND
MILLERMATIC
parts
that
come
in
contact
with
the
welding
ANY
IMPLIED
WARRANTY,
GUARANTY
OR
REPRESENTA-
~
wire
including
nozzles
and
nozzle
insulators
where
failure
does
TION
AS
TO
PERFORMANCE,
AND
ANY
REMEDY
FOR
not
result
from
defect
in
workmanship
or
material.
BREACH
OF
CONTRACT
WHICH,
BUT
FOR
THIS
PROVISION,
k.~
MIGHT
ARISE
BY
IMPLICATION,
OPERATION
OF
LAW,
Miller
shall
be
required
to
honor
warranty
claims
on
war-
CUSTOM
OF
TRADE
OR
COURSE
OF
DEALING,
INCLUDING
ranted
Equipment
in
the
event
of
failure
resulting
from
a
defect
ANY
IMPLIED
WARRANTY
OF
MERCHANTABILITY
OR
OF
within
the
following
periods
from
the
date
of
delivery
of
Equip-
FITNESS
FOR
PARTICULAR
PURPOSE,
WITH
RESPECT
TO
ment
to
the
original
user:
ANY
AND
ALL
EQUIPMENT
FURNISHED
BY
MILLER
IS
EX
CLUDED
AND
DISCLAIMED
BY
MILLER.
)
1.
Arc
welders,
power
sources
and
components
.
1
year
2.
Original
main
power
rectifiers
3
years
EXCEPT
AS
EXPRESSLY
PROVIDED
BY
MILLER
IN
(labor
-
1
year
only)
WRITING,
MILLER
PRODUCTS
ARE
INTENDED
FOR
3.
Allweldinggunsandfeeder/guns
90days
ULTIMATE
PURCHASE
BY
COMMERCIAL/INDUSTRIAL
4.
All
other
Millermatic
Feeders
1
year
USERS
AND
FOR
OPERATION
BY
PERSONS
TRAINED
AND
5.
Replacement
or
repair
parts,
exclusive
of
labor
60
days
EXPERIENCED
IN
THE
USE
AND
MAINTENANCE
OF
6.
Batteries
6
months
WELDING
EQUIPMENT
AND
NOT
FOR
CONSUMERS
OR
CONSUMER
USE.
MILLER
WARRANTIES
DO
NOT
EXTEND
provided
that
Miller
is
notified
in
writing
within
thirty
(30)
days
TO,
AND
NO
RESELLER
IS
AUTHORIZED
TO
EXTEND
of
the
date
of
such
failure.
MILLERS
WARRANTIES
TO,
ANY
CONSUMER.
~.
SECTION
1
-
INTRODUCTION
Ampere
Rating
100%
Duty
Cycle
Cable
And
Dimensions
Approx.
Weight
Model
300
Ampere
dcrp
CO2
I
Argon
300
I
200
Amps.
I
Amps.
Hose
Length
10
Ft.
15
Ft.
Cooling
Method
Air
In
Inches
In
Pounds
Height
Length
6-1/2
I13-1/2~
~
Net
I
Shipping
9
I
10
12
I
13
400
Ampere
400
I
Amps
10
Ft.
15
Ft.
Air
6-1/2
113112
10
I
ii
13
14
1-1.
GENERAL
This
manual
has
been
prepared
especially
for
use
in
familiar
izing
personnel
with
the
design,
installation,
operation,
main
tenance,
and
troubleshooting
of
this
equipment.
All
informa
tion
presented
herein
should
be
given
careful
consideration
to
assure
optimum
performance
of
this
equipment.
1-2.
RECEIVING-HANDLING
Prior
to
installing
this
equipment,
clean
all
packing
material
from
around
the
unit
and
carefully
inspect
for
any
damage
that
may
have
occurred
during
shipment.
Any
claims
for
loss
or
damage
that
may
have
occurred
in
transit
must
be
filed
by
the
purchaser
with
the
carrier.
A
copy
of
the
bill
of
lading
and
freight
bill
will
be
furnished
by
the
carrier
on
request
if
occasion
to
file
claim
arises.
When
requesting
information
concerning
this
equipment,
it
is
essential
that
Model
Description
and/or
Stock
Number
and
Serial
(or
Style)
Numbers
of
the
equipment
be
supplied.
1-4.
SAFETY
Before
the
equipment
is
put
into
operation,
the
safety
sec
tion
at
the
front
of
the
welding
power
source
or
welding
generator
manual
should
be
read
completely.
This
will
help
avoid
possible
injury
due
to
misuse
or
improper
welding
applications.
The
following
definitions
apply
to
CAUTION,
IMPORTANT,
and
NOTE
blocks
found
throughout
this
manual:
p;Ir~~Ii.i~.~
Under
this
heading,
installation,
operati.ng,
and
main
tenance
procedures
or
practices
will
be
found
that
if
not
carefully
followed
may
create
a
hazard
to
per-
sonnel.
U
.
This
gun
is
manufactured
in
two
model
classifications:
300
amp
and
400
amp.
Both
models
are
air
cooled
and
are
designed
specifically
for
the
Gas
Metal-Arc
Welding
(GMAW)
process.
The
design
features
of
the
300
amp
model
permits
use
of
.030,
.035,
.045
diameter
hard
wire
and
.045
diameter
flux
cored
wire.
This
gun
is
rated
at
300
amperes,
100
percent
duty
cycle
when
used
with
CO2
shielding
gas.
The
design
features
of
the
400
amp
model
permits
use
of
either
flux
cored
or
hard
wires
having
diameters
.045,
1/16.
and
5/64.
This
gun
is
rated
at
400
amperes,
100
percent
duty
cycle
when
used
with
CO2
shielding
gas.
The
gun
is
shipped
with
the
proper
components
installed
for
wire
size
ordered.
N
I
Under
this
heading,
installation,
operating,
and
main
tenance
procedures
or
practices
will
be
found
that
if
not
carefully
followed
may
result
in
damage
to
equip
ment.
NOTE
Under
this
heading,
explanatory
statements
will
be
found
that
need
special
emphasis
to
obtain
the
most
efficient
operation
of
the
equipment.
SECTION
2
-
INSTALLATION
I
Prior
to
installing
the
gun,
ensure
that
the
control!
feeder
and
welding
power
source
are
both
completely
disconnected
from
their
respective
input
electrical
power
supplies.
2-1.
GAS
HOSE
CONNECTIONS
(Figure
2-1)
Connect
the
gas
hose
from
the
gun
to
the
gas
connection
on
the
control/feeder
and
tighten.
This
fitting
has
a
right-hand
thread.
2-2.
CONTROL
SWITCH
RECEPTACLE
(Figure
2-1)
Insert
the
two-prong
twistlock
plug
from
the
gun
control
cable
into
the
control
switch
receptacle
on
the
control/feeder
and
rotate
plug
clockwise.
2-3.
WELD
CABLE
CONNECTIONS
(Figure
2-1)
Connect
the
weld
power
cable
from
the
gun
to
the
weld
cable
connector
on
the
control/feeder.
Tighten
the
nut
on
this
connection.
2-4.
CONTACT
TUBE
AND
WIRE
GUIDE
Contact
tubes
usually
have
the
wire
size
they
are
designed
for
stamped
on
the
tube
body.
Check
the
Contact
tube
to
make
sure
it
is
the
correct
size
for
the
wire
being
used.
Check
the
wire
guides
on
the
control/feeder
to
make
sure
they
are
the
correct
size.
2-5.
OUTLET
GUIDE
CONNECTIONS
A.
For
guns
to
be
used
with
SWINGARC
SINGLE
or
SWINGARC
DUAL
units:
.
same
size
as
the
outlet
guide
on
the
gun.
1.
Screw
desired
size
outlet
guide
into
threaded
end
of
outlet
guide
adapter.
1-3.
DESCRIPTION
U
U
U
U
I
I
U
U
OM-1023
Page
1
2.
Insert
outlet
guide
on
the
gun
into
outlet
guide
adapter
with
flat
side
toward
set
screw.
Secure
adapter
tightening
setscrew.
6.
Tighten
the
locking
screws.
3.
ProceedtoStepBl.
B.
For
guns
to
be
used
with
all
other
control/feeders:
(Figure
2-1)
1.
Ensure
that
proper
size
components
are
installed
in
the
gun
assembly
and
the
control/feeder
for
the
wire
size
being
used
(refer
to
respective
parts
list).
2.
Thread
the
electrode
wire
through
the
drive
roll
of
the
control/feeder
so
it
extends
about
3
inches
beyond
the
outlet
guide
hole.
3.
Close
and
secure
the
gear
cover(s).
4.
Slide
the
outlet
guide
over
the
wire
and
into
the
drive
roll
assembly
housing.
5.
Ensure
that
the
flat
side of
the
outlet
guide
is
facing
the
setscrew.
IMPORTANT
I
The
outlet
guide
should
be
positioned
as
close
as
possible
to
the
drive
rolls
without
touching
them.
This
gives
the
maximum
column
wire
strength
thus
elimin
ating
waves
in
the
wire.
When
more
pressure
is
applied
at
any
time
the
clearance
should
be
rechecked
on
all
guides.
-
SECTION
3
-
SEQUENCE
OF
OPERATION
3-1.
GAS
METAL-ARC
WELDING
(GMAW)
1.
Ensure
that
proper
electrical
connections
have
been
made
to
the
welding
power
source
and
the
control/
feeder
(refer
to
the
respective
Owners
Manuals).
2.
Ensure
that
the
proper
shielding
gas
is
connected
to
the
control/feeder.
3.
Ensure
that
the
welding
wire
has
been
properly
threaded
and
that
correct
initial
tensions
have
been
set
on
the
control/feeder
(refer
to
the
control/feeder
Owners
Manual).
4.
Turn
on
the
shielding
gas
supply.
5.
Place
controls
on
the
control/feeder
in
the
required
positions
for
the
welding
set
up.
6.
Energize
the
control/feeder
(the
welding
power
source
must
be
energized
if
the
control/feeder
power
input
is
connected
to
the
welding
power
source).
welding
power
sou
rce
is
e
nergized
a
nd
t
he
switch
lever
on
the
gun
is
depressed,
open-circuit
~ltage
will
be
present
on
the
welding
wire
and
any
metal
part
making
contact
with
it.
r~T
When
installing
new
equipment,
or
after
prolonged
shutdown,
allow
shielding
gas
to
flow
continuously
for
at
least
one
minute
prior
to
welding
in
order
to
purge
the
shielding
gas
line.
Place
the
Wire
Speed
control
to
the
minimum
setting
to
avoid
wasting
the
welding
wire
while
purging.
8.
Actuate
the
swtich
on
the
gun
handle
to
run
the wire
out
beyond
the
end
of
the
gas
nozzle
(if
applicable).
Cut
the
wire
off
approximately
1/4
to
3/8
from
the
nozzle.
9.
Set
the
Wire
Speed
control
on
the
control/feeder
slightly
in
excess
of
anticipated
wire
speed.
-
better
to
have
t
he
re
speed
rate
too
f
ast
th
an
too
slow.
If
the wire
feed
rate
is
too
slow
upon
initial
welding,
the
wire
may
burn back
into
the
contact
tube,
thus
damaging
it.
10.
Place
the
controls
on
the
welding
power
source
in
the
required
position
for
the
welding
set
up
(refer
to
welding
power
source
Owners
Manual).
11.
Energize
the
welding
power
source.
Prior
to
welding,
it
is
imperative
that
rprotective
clothing
(welding
coat
and
gloves)
end
eye
protection
(glasses
and/or
welding
helmet)
be
put
on.
Failure
to
comply
may
result
in
serious
or
permanent
bodily
damage.
12.
Hold
the
end
of
the
gas
nozzle
approximately
1/2
from
the
workpiece.
Ensure
Gear
Cover
Is
Down
And
Secured
Prior
To
Installing
Outlet
Guide
Outlet
Guide
Should
Not
Touch
Gears.
Control
Switch
j
Gas
Out
Connection
I
Connection
I
Outlet
Guide
Screw
I
weld
Cable
Connector
Assembly
Figure
2-1.
Gun
to
Control/Feeder
Connections
TC-056
811-4
I
.1
I
7.
Press
the
Purge
button
(if
applicable)
or
the
switch
lever
on
the
gun
handle
to
purge
the
gas
line.
The
welding
wire
and
all
metal
parts
in
contact
with
it
are
energized
while
welding.
Do
not
touch
the
welding
wire
or
any
metal
part
making
contact
with
it.
Page
2
13.
Press
the
switch
lever
on
the
gun
handle.
Gas
will
start
to
flow,
wire
will
start
to
feed
and
the
arc
will
be
established.
If
wire
slippage
is
noticed,
tighten
drive
roll
pressure
adjustment
1/4
turn
at
a
time
until
slippage
stops.
Do
not
overtighten.
Ensure
that
the
welding
power
sou~~s
completely
shut
down
and
that
power
is
removed
from
the
control/feeder
prior
to
performing
drive
roll
pressure
adjustment.
I
IMPORTANT
I
Whenever
drive
roll
pressure
is
adjusted
inlet
and
outlet
guide
clearance
must
be
rechecked.
14.
After
the
controls
on
the
welding
power
source
and
the
control/feeder
have
been
adjusted
for
normal
operation,
the
control/feeder
and
welding
power
source
will
function
automatically
whenever
the
gun
switch
is
depressed.
Releasing
the
gun
switch
lever
will
extinguish
the
arc
and
cause
wire
feed
and
gas
flow
to
stop.
3-2.
SHUTTING
DOWN
1.
Turn
off
the
shielding
gas
at
the
source.
If
welding
is
performed
in
a
confined
area,
failure
to~
turn
off
the
shielding
gas
supply
could
result
in
a
buildup
of
gas
fumes,
thereby
endangering
personnel
reentering
the
welding
area.
2.
Deenergize
the
control/feeder
and
the
welding
power
source.
SECTION
4
-
MAINTENANCE
Ensure
that
the
welding
power
source
is
completely
shut
down
and
that
power
is
removed
from
the
control/feeder
prior
to
attempting
maintenance
work
on
this
gun
qr
associated
equipment.
4-1.
INSPECTION
AND
UPKEEP
Usage
and
shop
conditions
will
determine
frequency
and
type
of
maintenance
required.
1.
Inspect
gun
for
broken
areas,
cracks
and
loose
parts;
tighten,
repair
and
replace
as
required.
2.
Carefully
remove
any
weld
spatter
or
foreign
matter
which
may
accumulate
around
the
nozzle
orifice.
3.
Remove
any
accumulation
around
the
switch.
4.
Repair
or
replace
as
required
all
hose
and
cabling;
give
particular
attention
to
frayed
and
cracked
insulation
and
areas
where
it
enters
equipment.
5.
Remove
grease
and
grime
from
components;
moisture
from
electrical
parts
and
cables.
6.
Blow
out
the
casing
with
compressed
air
when
changing
wire.
This
removes
any
metal
chips
and
dirt
that
may
have
accumulated.
4-2.
CHANGING
WIRE
SIZES
(Monocoil)(Figure
4-1)
CAUTION
that
the
welding
power
source
is
completely
shut
down
and
that
power
is
removed
from
the
control/feeder
prior
to
changing
the
wire,
control/
feeder
components,
or
gun
components.
Each
time
wire
size
is
changed,
the
gun
and
control/feeder
must
be
adapted
for
use
with
the
new
size
wire.
Refer
to
the
Control/Feeder
Owners
Manual
for
information
involving
changes
in
the
control/feeder
that
are
required
to
handle
different
wire
sizes.
Proceed
as
follows
when
changing
wire
size
with
the
monocoil
assembly
to
help
ensure
proper
installation.
~gu!!isequi&for.o3oor.o35wjreanditis
desired
to
convert
from
one
of
these
wire
sizes
to
the
other,
only
the
contact
tube
(item
4,
Figure
4-1)
will
have
to
be
changed.
However,
if
the
gun
is
equipped
for
.030
or
.035
wire
and
it
is
desired
to
convert
to
.045
wire
(or
vice
versa),
all
of
the
following
steps
will
i
have
to
be
performed.
1.
Cut
the
weld
bead
knob
off
the
end
of
the
welding
wire
at
the
gun
nozzle
(2).
2.
Loosen
the
outlet
guide
locking
screw
and
pull
the
outlet
guide
from
the
control/feeder
(Figure
2-1
3.
Cut
the
welding
wire
where
it
enters
the
outlet
guide
(19).
Pull
the
wire
out
of
the
monocoil
assembly
from
the
end
with
the
outlet
guide.
Remove
screw
(16)
and
Strain
relief
(15).
Remove
nozzle
(2).
contact
tube
(4),
and
contact
tube
adapter
(5).
Install
new
items
in
reverse
order
just
given.
6.
Slide
insulating
band
(1)
off
gun
and
remove
flat
head
screw
(10).
7.
Pull
handle
(12)
back
about
six
inches.
Pull
switch
wires
back
along
with
handle
(12)
to
avoid
jamming.
8.
Remove
outlet
guide
(19).
9.
Loosen
setscrew
(18)
and
remove
monocoil
connector
(17).
10.
Loosen
setscrew
(9)
and
pull
monocoil
liner
(14)
out
of
outlet
guide
end
and
install
new
monocoil
liner
(14).
11.
Secure
monocoil
liner
(14)
by
tightening
setscrew
(9).
12.
Install
new
monocoil
connector
(17)
securing
mono-
coil
liner
(14)
to
monocoil
connector
(17)
by
tighten.
ing
setscrew
(18).
13.
Slide
handle
(12)
onto
head
tube
(6)
and
secure
with
flat
head
screw
(10).
Slide
insulating
band
(1)
over
screw
(10).
14.
Install
outlet
guide
(19)
on
monocoil
connector
(17).
15.
Install
strain
relief
(15)
onto
outlet
guide
(19)
and
secure
with
screw
(16).
CAUTION
4
5
OM-1023
Page
3
Each
time
wire
size
is
changed,
the
gun
and
control/feeder
must
be
adapted
for
use
with
the
new
size
wire.
Refer
to
the
Control/Feeder
Owners
Manual
for
information
involving
changes
in
the
control/feeder
that
are
required
to
handle
different
wire
sizes.
1.
Band,
Insulator
2.
Nozzle
3.
Insulator,
Nozzle
4.
Tube,
Contact
5.
Adapter,
Contact
Tube
6.
Tube,
Head
7.
Screw,
Set
10-32
x
3/8
8.
Connector,
Conduit
or
Monocoil
9.
Screw,
Set
10-32
x
3/16
(300
Amp
Model
Only)
10.
Screw,
Machine
10-32
x
3/8
7
11.
Switch
&
Housing
Assembly
12.
Handle
13.
Monocoil
Casing
(300
Amp
Models)
Conduit
(400
Amp
Models)
14.
Liner,
Monocoji
15.
Spring,
Strain
Relief
16.
Screw,
Round
Head
10-32
x
1/2
17.
Connector,
Monocoil
18.
Screw,
Set
19.
Guide,
Outlet
10
Proceed
as
follows
when
changing
wire
size
with
the
conduit
assembly
to
help
ensure
proper
installation.
p
NOTE
If
the
gun
is
equipped
for
1/16
or
5/64
wire
and
it
is
desired
to
convert
from
one
of
these
wire
sizes
to
the
other,
Only
the
contact
tube
(item
4,
Figure
4-1
)
will
have
to
be
changed.
However,
if
the
gun
is
equipped
for
1/16
or
5/64
wire
and
it
is
desired
to
convert
to
.045
wire
(Or
vice
versa),
all
of
the
following
steps
will
have
to
be
performed,
I
1.
Cut
the
weld bead
knob
off
the
end
of
the
welding
wire
at
the
gun
nozzle
(2).
2.
Loosen
the
outlet
guide
locking
screw
and
pull
the
outlet
guide
from
control/feeder
(Figure
2-1).
3.
Cut
the
welding
wire
where
it
enters
the
outlet
guide
(19).
Pull
the
wire
out
of
the
conduit
(13)
from
the
end
with
the
outlet
guide.
4.
Remove
nozzle
(2),
contact
tube
(4),
and
contact
tube
adapter
(5).
Install
new
items
in
reverse
order
just
given.
TC-056
811-3
Figure
4-1.Installing
Conduit
AndMonocoil
Wire
Guide
Kits
16.
Install
outlet
guide
(19)
into
control/feeder
and
proceed
with
welding
operations.
4-3.
CHANGING
WIRE
SIZES
(Conduit)(Figure
4-1)
CAUTION
I
Ensure
that
the
welding
power
sour~
completely
shut
down
and
that
power
is
removed
from
the
control/feeder
prior
to
changing
the
wire,
control/
feeder
components,
or
gun
components.
5.
Slide
insulating
band
(1)
off
gun
and
remove
flat
head
screw
(10).
6.
Pull
handle
(12)
back
about
six
inches.
Pull
switch
wires
back
along
with
handle
(12)
to
avoid
jamming.
7.
Loosen
setscrew
(7)
and
pull
out
conduit
connector
(8)
from
head
tube
(6).
8.
Unscrew
conduit
connector
(8)
from
conduit
assembly
(13)
and
pull
conduit
assembly
(13)
Out
of
gun
handle
(12).
9.
Remove
screw
(16)
from
outlet
guide
(19)
and
pull
off
strain
relief
(15).
10.
Unscrew
outlet
guide
(19)
from
conduit
(13).
11.
Install
new
outlet
guide
(19)
onto
conduit
(13).
12.
Secure
strain
relief
(15)
to
outlet
guide
(19)
with
screw
(16).
13.
Insert
the
new
conduit
(13)
through
the
bottom
of
handle
(12).
14.
Remove
0-Ring
from
connector
(8)
and
install
on
new
connector
(8)
if
applicable.
15.
Secure
new
conduit
Connector
(8)
onto
the
conduit
(13).
16.
Slide
handle
(12)
onto
head
tube
(6)
and
secure
with
flat
head
screw
(10).
Slide
insulating
band
(1)
over
screw
(10).
17.
Install
outlet
guide
(19)
into
control/feeder
and
proceed
with
welding
operations.
1
1
3.
LEGEND
I
I
U
8
12
17
13
NOTE:
Items
8
&
9
assembled
at
factory.
Page
4
January
1980
FORM:
OM-1023B
PARTS
LIST
Effective
With
Style
No.
JA-2
MODEL
MMT-300A1
MMT-400A1
Model
3
Figure
A
Gun
Assembly
(400
Ampere
Conduit
Model
Illustrated)
J32
Includes
Item
36
300
Amp
400
Amp
Wire
Size
Wire
Size
.8MM
.9MM
1.2MM
.031
.036
.047
.030
.035
.045
1.2MM
1.6MM
2.0MM
.047
.063
.079
.045
1/16
5/64
2
1
49
4
48
Includes
Item
10
37
25
30
36
31
TC-056
811-C
OM-1
023
Page
1
Item
Part
No.
No.
Figure
A
Gun
Assembly
Description
Quantity
Model
300
400
Amp
Amp
1
*056
710
2
056816
2
056818
3
054
572
4
007319
4
007
321
4
007
318
4
007
320
4
007317
4
007
322
4
056
895
4
056
900
4
056
896
4
056
901
4
056 897
4
056
902
5
*056
820
5
*~35~
821
5
*056
822
5
*056
823
5
*056
824
6
056
825
6
056
826
7
007
330
7
007
332
8
058
174
9
056
652
9
056
653
9
056619
9
056
621
9
057218
9
057
220
9
057
219
9
057
221
10
057083
10
056741
10
056836
11
058190
12
058
192
13
058
191
14
604771
15
056610
16
602090
17
056831
18
056832
19
056833
19
056443
20
600
330
20
600
330
21
056803
22
056
854
23
056
479
24
602
088
INSULATOR,
nozzle
11/16
inch
NOZZLE,
5/8
orifice
2-5/8
long
NOZZLE,
5/8
orifice
2-3/4
long
BAND,rubberl-1/18lDx3/64widex3/4
KIT-WIRE,
guide
.030
10
ftor
KIT-WIRE,
guide
.030
wire
15
ft
(See
Fig
B
Page
4)
KIT-WIRE,
guide
.035
wire
loft
or
KIT-WIRE,
guide
.035
wire
15
ft
(See
Fig
B
Page
4)
KIT-WIRE,
guide
.045
wire
10
ft
or
KIT-WIRE,
guide
.045
wire
lSft
(See
Fig
B
Page
4)
KIT-WIRE,
guide
.045
wire
10
ft
or
KIT-WIRE,
guide
.045
wire
15
ft
(consisting
of)
KIT-WIRE,
guide
1/16
wire
lOft
or
KIT-WIRE,
guide
1/16
wire
15
ft
(consisting
of)
KIT-WIRE,
guide
5/64
wire
10
ft
or
KIT-WIRE,
guide
5/64
wire
15
ft
(consisting
of)
TUBE,
contact
.030
wire
TUBE,
contact
.035
wire
TUBE,
contact
.045
wire
TUBE,
contact
1/16
wire
TUBE,
contact
5/64
wire
ADAPTER,
tube
-
contact
.030-.045
wire
ADAPTER,
tube
-
contact
1/16
x
5/64
wire
CONNECTOR,
monocoil
(consisting
of)
CONNECTOR,
conduit
(consisting
of)
..O-RING,1/4x3/8
CONDUIT,
.080
ID
x
lOft
or
.CONDUIT,.O8OIDxl5ft
CONDUIT,
0.124
IDxl0ftor
.CONDUIT,0.l24IDxl5ft
MONOCOIL
ASSEMBLY,
.030
8
.035
lOft
or
MONOCOIL
ASSEMBLY,
.030
&
.035
l5ft
(See
Fig
B
Page
4)
MONOCOIL
ASSEMBLY,
.045
10
ft
or
MONOCOIL
ASSEMBLY,
.045
15
ft
(See
Fig
B
Page
4)
GUIDE,
outlet
.030
&
.035
wire
GUIDE,
outlet
.045
wire
GUIDE,
outlet
1/16
x
5/64
wire
TUBING,
neoprene
5/8
ID
x
3/32
waIl
x
4-5/8
INSULATOR,
body
-
head
tube
TUBE,
head
SCREW,
set
-
steel
10-32
x
1/8
LINER,
tube
head
SCREW,
machine
-
steel
flat
hd
10-32
x
3/8
HANDLE
CABLE
ASSEMBLY,
welding
10
ft
or
CABLE
ASSEMBLY,
welding
15
ft
(consisting
of)
CONNECTOR,
torch
end
CABLE,
weld
-
copper
stranded
No.
1/0
hypalon
(order
by
ft)
CABLE,
weld
-
copper
stranded
No.
1/0
hypalon
(order
by
ft)
LUG,
swedge
on
1/0-2/0
cable
TUBING,
heat
shrink
3/8
dia
x
2-1/2
SPRING,
strain
relief
SCREW,
machine
-
steel
round hd
10-32
x
1/4
1
1
1 1
1
1
1 1
1
1
1 1
1
1
1
1
1
1
lOft
lOft
15ft
l5ft
1
1
1
1
1
1
1 1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1 1
1
1
1
1
1
1
1
1
1
1
OM-1023
Page
2
Item
Part
No.
No.
Description
Quantity
Model
300
400
Amp
Amp
Figure
A
Gun
Assembly
(Contd.)
25
056
834
25
056
835
26
056
848
27
056
849
28
056
108
29
604
550
29
604
550
30
010606
31
056
851
32
057
782
32
057
783
33
604
523
34
604
524
35
604 525
35
604
525
36
604 848
37
056 830
38
604 848
39
056
296
40
604
525
41
604 866
42
059
294
43
053
132
44
059
258
45
056 845
46
056
846
47
059
290
48
059 293
49
604 937
50
604
607
TUBING,
plastic
No.
4
CORD,
portable
No.18
2/C
(order
byft)....
SWITCH,
licon
16-3022
SPRING,
compression
STRAIN
RELIEF,
cable
BLOCK,
mounting
-
switch
HOUSING,
switch
-
torch
LEVER,
actuating
-
switch
torch
NUT,
speed
-
push
on
RIVET,
steel
-
flared
hd
7/32
dia
x
1-1/4
SCREW,
self
-
tapping
pan
hd
6-32
x
1/4
SCREW,
machine-steel
10-32x3/4
2
lOft
15
ft
9ft
14
ft
2
*Recommended
Spare
Parts.
BE
SURE TO
PROVIDE
MODEL,
STYLE
NUMBER
AND
WIRE
SIZE
WHEN
ORDERING
REPLACEMENT
PARTS.
r
HOSE
ASSEMBLY,
gas
10
ft
or
HOSE
ASSEMBLY,
gas
15
ft
(consisting
of)
FITTING,
hose
-
brass
barbed
nipple
3/16
TBG
FITTING,
hose
-
brass
nut
No.
10
3/8-24
RH
FITTING,
hose
-
brass
ferrule
0.425
ID
x
23/32
HOSE,
neoprene
No.1
x3/161D(orderbyft)or
HOSE,
neoprene
No.1
x3/161D(orderbyft)
FITTING,
hose-brass
nut5/8-18
RH
FITTING,
hose
-
brass
barbed
nipple
3/16
TBG
CORD
ASSEMBLY,
switch
8
ft
2
inches
or
CORD
ASSEMBLY,
switch
13ft2
inches
(consisting
of)
CAP,
twistlock
-
midget
2P2W
COVER,
seal
-
tite
receptacle
CORD,
portable
18/2
(order
by
ft)
or
CORD,
portable
18/2
(order
byft)
TERMINAL,
disk
-
knife
16-22
wire
SWITCH
&
HOUSING
ASSEMBLY
(consisting
of)
TERMINAL,
disk
-
knife
16-22
wire
2
lOft
15
ft
9
ft
14
ft
2
2
2
3ft
1
1
1
1
1
1
1
2
1
3ft
1
1
1
1
1
1
1
1
2
1
Page
3
Item
Part
No. No.
Description
Quantity
Figure
B
Monocoil
Assemblies
CONNECTOR,
monocoil
.030
8-
.035
wire
CONNECTOR,
monocoil
.045
wire
FITTING,
brass
-
barbed
liner
FITTING,
hose
-
brass
nut
9/16-18
FITTING,
hose
-
brass
ferrule
0.475
ID
x
23/32
TUBING,
neoprenel7/64IDx1/20D(orderbyft)
LINER,
monocoil
.030
&
.035
wire
10
ft
LINER,
monocoil
.O45wire
lOft
LINER,
monocoil
.030
8
.035
wire
15
ft
LINER,
monocoil
.045
wire
15
ft
CONNECTOR,
monocoil
.030
8-
.035
wire
CONNECTOR,
monocoil
.045
wire
0-RING,
1/4x3/8
71
72
73
74
75 76
74
77
78
TA-057
072-B
Figure
B
-
Monocoil
Assembly
Quantity
Model
300
400
Description
Amp
Amp
Optional
Parts
056815
1
056817
1
056816
1
056818
1
056819
1
t057
737
1
058
348
1
058
353
1
058
354
1
058
355
1
058
356
1
058391
058392
058
393
058
402
71
057307
71
057
308
72
057
309
73
602
959
74
056112
75
605
545
76
056
758
76
056 760
76
056
759
76
056
761
77
058
679
77
058
680
78
058
174
2
As
Reqd
Part
No.
NOZZLE,
1/2
orifice
2-5/8
long
NOZZLE,
1/2
orifice
2-3/4
long
NOZZLE,
5/8
orifice
2-5/8
long
NOZZLE,
5/8
orifice
2-3/4
long
NOZZLE,
3/4
orifice
2-3/4
long
TUBE,
contact
.052
wire
INSULATOR,
nozzle
w/retaining
ring
NOZZLE,
spot
-
flat
13/16
ID
x
3-5/8
NOZZLE,
spot
-
outside
corner
13/16
ID
x
4-1/8
NOZZLE,
spot
-
inside
corner
13/16
ID
x
3-5/8
NOZZLE,
spot
-
all
purpose
13/16
ID
x
3-5/8
NOZZLE,
spot
-
inside
corner
1-1/8
ID
x
4-1/16
NOZZLE,
spot
-
all
purpose
1-1/8
ID
x4-1
/16
NOZZLE,
spot
-
outside
corner
1-1/8
ID
x
4-1/16
NOZZLE,
spot-flat
1-1/8
ID
x4-1/16
tCan
be
used
with
.045
wire
guide
kits.
BE
SURE
TO
PROVIDE
MODEL
AND
SERIAL
NUMBERS
WHEN
ORDERING
REPLACEMENT
PARTS.
1
1
1
1
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Miller MMT-400A1 Owner's manual
- Category
- Welding System
- Type
- Owner's manual
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