Miller Electric MT-24-12-1 User manual

I,
Millerfi
November
1990
FORM: OM-1558A
Effective With
Style
No.
KB-8
MODEL:
MT-24-12-1
MT-24-25-1
MT-24F-1
2-1
MT-24
F-25-1
MT-24VF-12-1
MT-24VF-25-1
OWNERS
MANUAL
IMPORTANT:
Read and
understand
the
entire
contents
of both this
manual
and the
power
source
manual
used
with this
unit,
with
special
emphasis
on
the
safety
material
throughout
both
manuals,
before
installing, operating,
or
maintaining
this
equipment.
This
unit and these
instructions
are
for
use
only
by
persons
trained and
experienced
in the
safe
operation
of
welding
equip
ment.
Do
not
allow untrained
persons
to
install,
operate,
or
maintarn
this unit.
Contact
your
distributor
if
you
do
not
fully
understand
these
instructions.
MILLER
ELECTRIC
Mfg.
Co.
A
Miller
Group
Ltd.,
Company
P.O.
Box
1079
Appleton,
WI
54912
USA
Tel.
414-734-9821
..,,n~
SA-120
672
PRINTED IN
U.S.A.

LIMITED WARRANTY
EFFECTIVE: AUGUST
6,
1990
lii
This
warranty
supersedes
all
previous
MILLER
warranties
and
is
exclusive
with
no
dther
guarantees
or
warranties
expressed
or
implied.
LIMITED
WARRANTY

Subject
to
the
terms
and
conditions
hereof,
MILLER
Electric
Mfg.
Co.,
Appleton,
Wisconsin
war
rants to
its
Distributor/Dealer
that
all
new
and
unused
Equipment
furnished
by
MILLER
is
free from
defect
in
workmanship
and
material
as
of
the
time
and
place
of
delivery
by
MILLER. No
warranty
is
made
by
MILLER
with
respect
to
engines,
trade
accessories
or
other items
manufactured
by
others,
Such
engines,
trade
accessories and other
items
are
sold
subject
to
the warranties
of their
respective
manufacturers,
if
any.
All
engines
are
warrant
ied
by
their
manufacturer
for
two
years
from date
of
original
purchase,
except
Deutz
engines
which
have
a
one
year,
2000 hour
warranty.
Except
as
specified
below,
MILLERs
warranty
does
not
apply
to
components
having
normal
useful
life
of less
than
one
(1)
year,
such
as
spot
welder
tips, relay
and
contactor
points,
MILLERMATIC
parts
that
come
in
contact
with
the
welding
wire
including
nozzles
and
nozzle
insulators where failure
does
not
result
from defect
in
workmanship
or
material.
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
Equipment
to
the
original
user;
1.
Arc
welders,
power
sources,
robots,
and
1
year
components
2.
Load
banks
1
year
3.
Original
main
power
rectifiers
3
years
(labor

1
year
only)
4.
All
welding
guns,
feeder/guns
and
torches
.
.
.
90
days
5.
All
other
MILLERMATIC
Feeders
1
year
6.
Replacement
or
repair
parts,
exclusive of labor 60
days
7.
Batteries
6
months
provided
that
MILLER
is
notified
in
writing
within
thirty (30) days
of the
date
of
such
failure.
As
a
matter
of
general policy
only,
MILLER
may
honor claims
submitted
by
the
original
user
within
the
foregoing
periods.
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
ment
or,
where authorized
in
writing 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
actual
use)
upon
return
of
the
goods
at
Customers
risk
and
expense.
MILLERs
option
of
repair
or
replacement
will
be
FOB..
Factory
at
Appleton.
Wisconsin.
or
F.O.B.
at a
MILLER
authorized service
facility,
therefore,
no
compensation
for
transportation
costs
of
any
kind
will
be allowed.
Upon
receipt
of
notice
of
apparent
defect
or failure,
MILLER
shall instruct the
claimant
on
the
warranty
claim
procedures
to
be followed.
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
IMPLICATION,
OPERATION
OF
LAW,
CUSTOM
OF TRADE
OR
COURSE
OF
DEALING,
INCLUDING
ANY
IMPLIED WARRANTY OF MERCHAN
TABILITY OR OF FITNESS
FOR
PARTICULAR
PURPOSE,
WITH RESPECT
TO
ANY AND ALL
EQUIPMENT
FURNISHED
BY MILLER
IS EXCLUDED
AND
DISCLAIMED
BY
MILLER.
EXCEPT
AS
EXPRESSLY PROVIDED BY MILLER
IN
WRITING,
MILLER
PRODUCTS
ARE INTENDED FOR
ULTIMATE
PURCHASE
BY
COMMERCIAL/INDUSTRIAL
USERS
AND FOR
OPERATION
BY
PERSONS
TRAINED
AND
EXPERIENCED
IN
THE
USE
AND
MAINTENANCE
OF
WELDING EQUIPMENT
AND
NOT FOR
CONSUMERS
OR
CONSUMER USE. MILLERS WARRANTIES DO NOT
EXTEND
TO,
AND NO
RESELLER
IS
AUTHORIZED
TO
EXTEND
MILLERS
WARRANTIES
TO,
ANY
CONSUMER.
I
ii
I

OM-1558A
11/90
RECEIVING-HANDLING
Before
unpacking equipment,
check
carton
for
any
dam- Use the
following
spaces
to
record the
Model
Designa
age
that
may
have
occurred
during
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
from
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
1-1.
Prevent
Electric Shock
1
1-2.
Provide
Protection
From
Fumes
And
Gases
1
1-3. Protect
Eyes
And
Skin
From
Arc
Rays;
Protect Ears
From
Noise
1
1-4.
Prevent Fires
And Burns
1
1-5.
Protect
Compressed
Gas
Cylinders
1
1-6.
Provide
Protection
For
Speial
Situations
1
1-7.
Provide
Proper
Equipment
Maintenance
2
1
-8.
Additional
Safety
Information
2
SECTION
2
SAFETY PRECAUTIONS
AND
SIGNAL WORDS
2-1.
General Information
And
Safety
3
2-2.
Safety
Alert
Symbol
And
Signal
Words
3
SECTION
3
SPECIFICATIONS
3-1.
Duty
Cycle
3
3-2.
Description
3
SECTION 4
INSTALLATION
4-1.
Torch
Body
4
4-2.
Gas
Hose
Connections
And
Gas
Valve
(If
Applicable)
5
4-3. Power
Cable Connection
6
SECTION
5
SEQUENCE
OF OPERATION
5-1.
Gas
Tungsten
Arc
Welding (GTAW)
6
5-2.
Shutting
Down
6
SECTION
6
MAINTENANCE
6-1.
Routine
M~intenance
7
6-2.
Tungsten
Electrode
7
SECTION 7
PARTS
LIST
Figure
7-1.
Complete
Torch
Assembly
9
Figure
7-2.
Consumable
Parts
And
Cross Reference Chart
10
LIST OF
CHARTS
AND
TABLES
Table
3-1.
Specifications
3
Table
6-1.
Maintenance Schedule
7
Table
6-2.
Tungsten
Size
8

SECTION
1

SAFETY
RULES
a
WARNING: UNSAFE
PROCEDURES OR
1-3.
PROTECT
EYES
AND
SKIN
FROM ARC
PRACTICES
can cause
serIous
personal
in-
RAYS;
PROTECT EARS
FROM
NOISE
jury
or
death.
Arc
rays
from the
welding
process
produce
intense heat

Read, understand,
and
follow
ALL
of these
and
strong
ultraviolet
rays
that
can
burn
eyes
and
skin.
safety
rules
before
installing,
operating,
or
servicing
this
equipment.
Noise
from
some
processes
can
damage
hearing.

Be
sure
that all
end
users
of
this
equipment,
1.
Wear
a
welding
helmet
fitted
with
a
proper
filter
the
operator
and
helpers,
read
and under-
lens
(see
ANSI
Z49.1 for
detailed
information).
stand these
safety
rules.
2.
Wear
a
welding
helmet
fitted
with
a
proper
filter
lens
(see
ANSI
Z49.1 for
detailed
information).
3.
Use
protective
screens or
barriers
to
protect
0th-
1-1.
PREVENT
ELECTRIC SHOCK
ers
from
flash
and
glare.
Touching
live electrical
parts
can
cause
severe
burns
to
~
Wear
protective clothing
and
foot
protection.
the
body
or
fatal shock.
Severity
of
electrical shock is de
1-4.
PREVENT
FIRES
AND
BURNS
term
med
by
the
path
and
amount
of
current
through
the
body.
Therefore:
The
hotworkpiece,
hot
equipment,
other
hot
metal,
spat
ter,
and
arc
sparks
can
cause
fires
and
burns.
1.
Do
not
touch
live electrical
parts.
1.
Wear
correct
eye,
face,
and
body
protection
in
the
2.. Do
not
work
in
wet
or
damp
areas.
work
area.
3.
Wear
dry insulating gloves
and
body
protection.
2.
Allow work and
equipment
to
cool
before han
dling.
4.
Disconnectallpowerbeforeinstallingorservicing
3.
Do
not
weld
near
flammable
material.
this
equipment.
4.
Watch for
fire,
and
keep
a
fire
extinguisher
5.
Turn
off
all
equipment
when
not
in
use.
nearby.
6.
Properly
install
and
ground
the
welding
power
5.
For
additional
information,
refer
to
NFPA
Stan-
source
according
to
its
Owners
Manual
and
all
dard 51
B,
Fire Prevention
in
Use
of
Cutting
and
applicable
codes.
Welding
Processes,
available
from
the National
Fire Protection
Association,
Batterymarch
Park,
7.
Do
not
use
worn or
damaged
cables
or
cables that
Quincy,
MA
02269.
are
too
small
or
poorly
spliced.
1-5.
PROTECT
COMPRESSED GAS
CYLINDERS
8.
Do
not
wrap
cables around
your
body.
Since
gas
cylinder
are
normally
part
of
the
welding
proc
9.
Do
not
touch
electrode and
any
grounded object
ess,
be
sure
to
treat
them
carefully.
or
circuit
at
the
same
time.
1.
Protect
compressed
gas
cylinders
from
exces
10.
,
Use
only
well-maintained
equipment. Repair
or
sive
heat,
mechanical
shocks,
and
arcs.
replace damaged
parts
at
once.
2,
Install and
secure
cylinder
so
that
they
cannot
fall
~r
tip
over
by
fastening
them
to
a
mounting
1-2.
PROVIDE
PROTECTION FROM
FUMES
AND
bracket,
wall,
or
other
stationary
support.
GASES
3.
Keep
cylinders
away
from
any
welding
or
other
electrical
circuits.
Breathing welding
fumes
and
gases
can
be hazardous
to
your
health.
4.
Never
allow
a
welding
electrode
to
touch
any
cyl
inder.
1.
Keep
your
head
out
of
the
fumes.
1-6.
PROVIDE
PROTECTION
FOR
SPECIAL
SITU-
2.
Use
adequate
ventilation
in
the work
areato
keep
ATIONS
fumes and
gases
from
your
breathing
zone
and
the
general
work
area.
1.
Do
not
weld
or
cut
containers
or
materials which
have held
or
been
in
contact
with
hazardous
sub
3.
If
ventilation
is
inadequate,
use an
approved
stances
unless
they
are
properly
cleaned
and
in
breathing
device.
spected.
4.
Read the
Material
Safety
Data
Sheets
(MSDSs)
2.
Do
not
weld
or
cut
painted
or
plated
parts
unless
and the
manufacturers instructions for
any
mate-
special
ventilation is
provided
to
remove
highly
rials
used.
toxic
fumes
or
gases.
OM-1558
Page
1

3.
Since
welding
can
affect
pacemakers,
keep
all
pacemaker
wearers
out
of
the
work
area.
Have
them
consult
a
doctor
before
coming
near
a
weld
ing
operation.
1-7.
PROVIDE PROPER
EQUIPMENT
MAINTE
NANCE
improperly
maintained
equipment
can
result
in
poor
work,
but
most
importantly
it
can cause
physical
injury
or
death
through
fires
or
electrical
shock. Therefore:
1.
Always
have
qualified
personnel
perform
the
in
stallation,
troubleshooting,
and
maintenance
work.
Do
not
perform
any
electrical
work
unless
you
are
fully
qualified.
2.
Before
performing
any
maintenance
work
inside
a
power
supply,
disconnect
the
power
supply
from
the
electrical
power
source.
3.
Maintain
cables,
grounding
wire,
connections,
power
cord,
and
power
supply
in
a
safe
working
order.
Do
not
operate
any
equipment
in
question
able
condition.
4. Do
not
abuse
any
equipment
or
accessories.
Keep
equipment
away
from heat
sources
such
as
furnaces,
wet
conditions
such
as
water
puddles,
oil
or
grease,
corrosive
atmospheres,
and inclem
ent
weather.
5.
Keep
all
safety
devices,
guards,
panels,
and
cov
ers
in
position
and
in
good
repair.
6.
Use
equipment
for
its
intended
purpose.
Do
not
modify
it
in
any
manner.
1-8.
ADDITIONAL
SAFETY
INFORMATION
For
more
information
on
safe
practices
for
setting
up
and
operating
electric
welding
and
cutting
equipment
and
on
good working
habits,
ask
your
welding
equipment
sup
plier.
For
your
protection,
read and
comply
with the
latest
editions
of the
following
standards:
1.
ANSI
Standard
Z49.t available from
the
Ameri
can
Welding
Society,
550
N.W.
LeJeune
Rd,
Mi
ami,
FL
33126.
2.
AWS
Standard
A6.1,
Recommended
Safe
Prac
tices
for
Gas
Shielded
Arc
Welding,
available
from
the
American
Welding
Society,
550
N.W.
LeJeune
Rd, Miami,
FL
33126.
3.
AWS
Standard
F4.1,
Recommended
Safe
Prac
tices for
the
Preparation
for
Welding
and
Cutting
of
Containers
and
Piping
That
Have Held
Hazard
ous
Substances,
available
from
the American
Welding
Society,
550
N.W.
LeJeune
Rd,
Miami,
FL
33126.
4.
NFPA Standard
51B,
Fire Prevention
in
Use of
Cutting
and
Welding
Processes,
available from
the National
Fire
Protection
Association,
Bat
terymarch
Park,
Quincy,
MA
02269.
5.
NFPA
Standard
70,
National
Electrical
Code,
available
from
the
National
Fire Protection Asso
ciation,
Batterymarch
Park,
Quincy,
MA
02269.
6.
ANSI
Standard
Z87.
1,
Safe
Practice
for
Occupa
tion and
Educational
Eye
and
Face
Protection,
available
from
the
American National Standards
Institute,
1430
Broadway,
New
York,
NY
10018.
7.
OSHA Standard
29
CFR,
Part
1910,
Subpart
0,
Welding,
Cutting,
and
Brazing,
available from
the
Superintendent
of
Documents,
U.S. Govern
ment
Printing
Office,
Washington,
DC
20402.
8.
CSA
Standard
Wi
17.2,
Code for
Safety
in
Weld
ing
and
Cutting,
available
from
the
Canadian
Standards
Association,
178
Rexdale
Blvd.,
Rex
dale,
Ontario,
Canada M9W
1
R3.
9.
See
also
the
Standards Booklet
Index
in
the
weld
ing
power
source
Owners
Manual.
I
OM-1558
Page
2

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.
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
in
accordance
with
this
manual
and
all
applicable
codes
such
as,
but
not
limited
to,
those
listed
at
the end
of Section
1

Safety
Rules.
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.
4~
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
ment.
SECTION 3 SPECIFICATIONS
Table
3-1.
Specifications
Model
Ampere
Rating
At
100%
Duty
Cycle
DCEN;
ACHF
Tun9sten
Size
Capacity
Cable
Length
Torch
Body
Cooling
Method
Wei
ght
Net
Ship
MT-24-12-1
MT-24-25-1
MT-24F-1
2-1
MT-24-VF-12-1
MT-24F-25-1
MT-24VF-25-1
80
Amperes
With
Argon*
.020 thru
3/32
in.
(0.5
thru
2.4
mm)
12.5
ft.
(3.8
m)
25
ft
(7.6 m)
Length:
8.1
in.
(206.0
mm)
Handle
Diameter:
0.75
in.
(19.0
mm)
Weight:
2.0
oz.
(57.0
g)
Air
2
lbs.
(0.9
kg)
2.5
lbs.
(1.1
kg)
4.5
lbs.
(2.0
kg)
5.0 lbs.
(2.3
kg)

12.5
ft.
(3.8 m)
25
ft.
(7.6 m)
Length:
8.0
in.
(203.0
mm)
Handle
Diameter:
0.75
in.
(19.0
mm)
Weight:
3.0
oz.
(85.0
g)
2
lbs.
(0.9
kg)
3
lbs.
(1.1
kg)
4.5
lbs.
(2.0
kg)
5.0 lbs.
(2.3
kg)
*Rated
With
Gas
Lens
Collet
Body
3-1.
DUTY
CYCLE
The
duty
cycle
of
a
welding
torch is the
percentage
of
a
ten
minute
period
that
a
torch
can
be
operated
at
a
given
load. This
torch
is rated
at
100%
duty
cycle
using
argon
shielding
gas.
This
means
that the torch
can
beoperated
at
rated
load
conditions
continuously.
CAUTION:
EXCEEDING
THE
RATED
AMPERAGE
and
duty cycle
can
result
in
damage
to
the
torch.

Do
not
exceed
rated
amperage
and
duty cycle
stated
in
Table 3-1.
3-2.
DESCRIPTION
This
air-cooled
torch
is
specifically
for
use
with
the
Gas
Tungsten
Arc
Welding
(GTAW)
process.
The
alphanu
meric
model
designation
refers
to
the
following:
24
-
Ampere Rating:
80
Amperes.
12-
12.5 ft.
(3.8
m)
Cable
25
-
25
ft.
(7.6
m)
Cable
1
-
One-Piece,
High-Flex
Cable
V
-
Gas
Valve
F
-
Flex
Head
a
OM-1
558
Page
3

SECTION 4
INSTALLATION
*Cup
~Tungsten
Electrode
Heat
Shield
Torch
Body
(Neck
Portion)
*POwer Cable
Adapter
Gas
Valve
(If
Applicable)
0-Ring
Handle
>
SA-120
671
Figure
4-1.
Torch
Components
4-1.
TORCH BODY
(Figure
4-1)
a
WARNING:
ELECTRIC SHOCK
can
kill.

Do
not
touch live
electrical
parts.

Shut
down
welding
power
source,
and dis
connect
input
power
employing lockout/tag
ging
procedures
before
installing
torch.
Lockoutltagging
procedures
consist
of
pad
locking
line
disconnect
switch
in
open
position,
removing
fuses
from fuse
box,
or
shutting
off
and
red-tagging
circuit breaker
or
other
discon
necting
device.
The torch
body
is
shipped
requiring
consumables and
accessories indicated
in
Figure
4-1:
Cup,
collet
body,
collet,
power
cable
adapter
(with
flex
cable
only),
and
tungsten
electrode.
A.
Assembly
Assemble torch
as
follows:
1.
Install
collet,
slotted end
last,
into collet
body.
2.
Install collet
body
and collet into
torch
body
making
sure
heat
shield
is
in
place.
3. Install
properly
prepared
tungsten
electrode
(see
Section
6-2)
into collet
body,
and
position
elec
trode
tip
outside
cup
rim.
Tighten
collet
body.
4.
Install
cup
onto
collet
body.
5.
To
readjust
electrode
position,
remove
cup
and
loosen
collet
body.
IMPORTANT:
As
a
general
rule,
electrode
extension
should
equal
electrode
diameter;
but
exact
electrode
ex
tension
may vary
according
to
application.
B.
Flexible
Head
Adjustment
a
CAUTION:
BENDING RIGID
HEAD
TORCH
can
damage
torch.

Do
not
bend
rigid
head
model
torches.
Warranty
is
void
if
rigid
head
torch
is
bent
in
any
manner.
Improper
bending
of
flexible
head
torch
can
damage
gas
hose.
Make
sureto
bend
onlywithin
the
middle
portion
of
torch
neck
(see
Figure
4-1).
Restrict
bending
angle
to
90
degrees.
*Collet
*ColIet
Body

-~
High
Flex
Cable
Fitting
*Required
Consumables
and Accessories
**Obtain
from
Welding
Equipment Supplier
OM-1
558
Page
4

4-2.
GAS
HOSE
CONNECTIONS
AND
GAS
VALVE
(If
Applicable)
(Figures
4-1
Thru
4-3)
IMPORTANT:
lfpower
source
is
not
equipped
with
a
gas
valve,
a
torch
gas
valve
is
required
(see
Figure 4-2).
A.
High
Flex
Cable
Assembly
The
high
flex
cable
assembly
contains
the
power
cable
within the
gas
hose.
The
high
flex cable has
a
3/8-24
fe
male
right-hand
fitting
(see
Figure
4-1).
Torch
To
install
high
flex
cable,
connect
high
flex
cable
fitting
to
power
cable
adapter.
If
torch
includes
a
gas
valve,
connect
a
suitable
length
of
gas
hose
(extra
hose
not
supplied)
from
power
cable
adapter
to
regulator/flowmeter
(see
Figure
4-2).
If
torch is
without
gas
valve,
connect
a
suitable
length
of
gas
hose
(not
supplied)
from
power
cable
adapter
to
gas
valve outlet.
Connect
extra
gas
hose
(not
supplied)
from
gas
valve
inlet
to
regulator/flowmeter
(see
Figure
4-3).
Torch
Work
Clamp
Figure
4-3.
GTAW
Torch
Connection
Diagram
For
Models
Without Gas
Valve
Gas
Cylinder
Ref.
SA.120
909
Regulator!
Flowmeter
Work
Clamp
Power
Cable
Adapter
Figure
4-2. GTAW
Torch
Connection
Diagram
For
Models
With
Gas
Valve
Rot.
SA.120
909
Power
Cable
Adapter
Gas
Valve
OM-1
558
Page
5

B.
Torch
Gas
Valve
Operation (If Applicable)
The
gas
valve allows
gas
flow control
at
the torch.
A
one-
half
turn
counterclockwise
opens
the
gas
valve,
and
a
one-half
turn clockwise
closes
the
valve.
The
gas
valve allows
control
of
gas
postflow
time,
or
the
length
of
time
gas
flows after
the
arc
is
extinguished.
In
sufficient
gas
postflow
results
in
an
oxidized
(black)
elec
trode
surface.
If
an
oxidized
electrode
were
used,
the
black
surface
would
contaminate
the weld and
cause
poor
arc
direction.
IMPORTANT:
As
a
general
rule,
allow
10
seconds
of
gas
postflow
time
per
100
amperes
of
weld
current
be
fore
closing
valve.
4-3.
POWER
CABLE
CONNECTION
(Figures
4-1
Thru
4-3)
a
WARNING:
ELECTRIC SHOCK
can
kill.

Do
not
touch
live
electrical
parts.

Shut
down
welding
power
source,
and dis
connect
in
put
power
employing
lockout/tag
ging
procedures
before
installing
torch.
Lockout/tagging
procedures
consist
of
pad
locking
line disconnect
switch
in
open
position,
removing
fuses
from
fuse
box,
or
shutting
off
and
red-tagging
circuit
breaker
or
other
discon
necting
device.
The
power
cable is
part
of
the
high
flex cable
assembly.
For
connection
of
both
power
cable and
gas
hose
to
power
cable
adapter,
see
Section
4-2A.
Connect
power
cable
adapter
to
weld
output
terminal
(see
Figures
4-2
and
4-3).
SECTION
5
SEQUENCE OF
OPERATION
a
WARNING:
ELECTRIC SHOCK
can
kill.

Do
not
touch live
electrical
parts.

Keep
all
covers
and handle
in
place
while
operating.
ARC
RAYS,
SPARKS,
AND
HOT SURFACES
can
burn
eyes
and
skin;
NOISE
can
damage
hearing.

Wear
correct
eye,
ear,
and
body
protection.
FUMES
AND
GASES
can
seriously
harm
your
health.

Keep
your
head
out
of the
fumes.

Ventilate
to
keep
from
breathing
fumes
and
gases.

If
ventilation is
inadequate,
use
approved
breathing
device.
HOT
METAL, SPATTER,
AND
SLAG
can
cause
fire
and burns.

Watch for fire.

Keep
a
fire
extinguisher
nearby,
and
know
how
to
use
it.

Do
not
use near
flammable
material.

Allow work
and
equipment
to
cool
before
handling.
MAGNETIC
FIELDS FROM
HIGH
CURRENTS
can
affect
pacemaker
operation.

Wearers
should
consult
their
doctor
before
going
near
arc
welding, gouging,
or
spot
weld
ing
operations.
See Section
1
-
Safety
Rules for
additional
information.
5-1.
GAS
TUNGSTEN
ARC
WELDING
(GTAW)
1.
Install
and
connect
torch
according
to
Section 4.
2.
Make
sure
collet
body,
cup,
and all
gas
connec
tions
are
securely
tightened.
3.
With
regulator/flowmeter
valve
closed,
open
gas
cylinder
valve.
4.
Set
power
source
for
desired
welding
amperage.
5.
Wear
dry
insulating
gloves
and
clothing,
and
wear
welding
helmet
with
proper
filter lens
according
to
ANSI
Z49.1.
6.
Energize welding
power
source.
7. Set
gas
flow
to
desired
level
(requires
open gas
valve).
IMPORTANT:
Purge
gas
hose
to
clear hose
of
air,
mois
ture,
or
any
other
contaminants.
Allow
gas
to
flow
2
to
3
minutes
on new
torch;
5
to
6 seconds
thereafter.
8.
Begin welding.
5-2.
SHUTTING DOWN
1.
Stopwelding.
IMPORTANT:
As
a
general
rule,
allow 10
seconds
of
gas
postflow
time
per
100
amperes
of
weld
current
be
fore
closing
valve.
2.
Turn
off
welding
power
source.
3.
Turn
off
the
shielding
gas
at
the
source.
a
WARNING:
HIGH
CONCENTRATION
OF
SHIELDING GAS
can
harm health
or
kill.

Shut
off
gas
supply
when
not
in
use.
OM-1558
Page
6