Miller ANALOG 300 User manual

August
1975
FORM:
OM-215A
Effective with serial
No.
HF859183
MODEL
ANALOG 300
W/ELECTROSLOPE
W/PULSER
W/ELECTROSLOPE
&
PULSER
MODEL/STOCK
NO.
SERIAL/STYLE
NO.
DATE
PURCHASED
ADDITIONAL
COPY
PRICE
$1.10
OWNERS
MANUAL
MILLER
ELECTRIC
MFG.
CO.
APPLETON,
WISCONSIN,
USA
54911
FILE
COPY
RETURN
TO
FOLDER
STOCK
NO.
901
408
901
410
901
417
NWSA
CODE
NO.
4579
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WARRANTY
MILLER
Electric
Mfg.
Co.,
Appleton,
Wisconsin,
warrants
all
new
equipment
to
be
free
from defects
in
~
c
material and
factory
workmanship
for
the
periods
indicated
below,
provided
the
equipment
is installed
and
operated
according
to
manufacturers instructions.
C
~
C
C)
C
MILLER
Electric
Mfg.
Co.s
obligation,
under
this
warranty,
is
limited
to
replacing
or
repairing
any
defective
~
C
part
or
correcting
any
manufacturing
defect without
charge
during
the
warranty
period
if
MILLERS
inspec
c
tion
confirms
the existence of
such defects.
MILLERS
option
of
repair
or
replacement
will
be
f.o.b.
factory
at
C
Appleton,
Wisconsin
or
f.o.b.
a
MILLER authorized
service
facility,
and
therefore
no
compensation
for
trans
portation
costs
of
any
kind
will
be
allowed.
The
warranty
period,
beginning
on
the date
of
sale
to
the
original purchaser-user
of
the
equipment,
will
be
as
follows:
1.
Arc
welders,
power
sources,
and
components

1
year
2.
Original
main
power
rectifiers

3
years
(unconditionally)
3.
MHFC-L1
Feeder, MHG-35C1,
20E,
20K,
and
all
guns
and
torches

90
day~
4.
All
other
Millermatic
Feeders

1
ye~r
5.
Mag-Diesel
engine
on
DEL-200

6
months
6.
All
other
engines

1
year
Engine
Warranties
are
covered
by
the
engine
manufacturers,
subject
to
their
procedures
and
to
be
handled
through
their
authorized
local
Service
Stations
or
agencies.
No
warranty
will
be
made
in
respect
to
trade
accessories,
such
being
subject
to
the
warranties
of their
respective
manufacturers.
MILLER
Electric
Mfg.
Co. will
not
be
liable
for
any
loss
or
consequential
damage
or
expense
accruing
directly
or
indirectly
from
the
use
of
equipment
covered
in
this
warranty.
This
warranty
supersedes
all
previous
MILLER
warranties
and
is
exclusive
with
no
other
guarantees
or
warranties
expressed
or
implied.
c
~*+~+~
~+
RHS-2
(Stock
No.
040
048)
Momentary
contact
(normally
open)
switch.
Attaches
to
the
TIG
torch
handle.
Used
for
on-off
control
of
contactor
or
for
triggering
Electroslopes.
Furnished
with
28
cord
and
twistlock
plug.
RHC-3-1010
(Stock
No.
040
832)
Remote hand
amperage
control
with
10
turn
direct
reading
(in
amperes)
digital
dial. Furnished with 20 cord and
3
prong
twistlock
plug.
RFS-2
(Stock
No.
040
064)
Maintained
contact
foot
operated
switch. Can
be
converted
to
a
momentary
type.
Used for
on-off
control of
contactor.
Furnished
with
28 cord
and
twistlock
plug.
RFCE-31
(Stock
No. 040
666)
Remote
foot
amperage
and
contactor
control,
1000 ohm. Two
20
cords. A 2
conductor
cord
terminates
in
a
2
prong
twistlock
cap
and
a
3
conductor
cord
terminates
in
a
3
prong
twistlock
cap.
No. 3
Running
Gear
(Stock
No. 040
016)
Three
pneumatic
rubber
tired wheels 16
in
diameter with
towing
handle.
Will
carry
welder,
two
gas
cylinders
and
water
coolant
system.

CERTI
FICATE
NAME OF
EQUIPMENT:_______________________
MODEL
NO.,________________
SERIAL NO.
_____________________________
DATF
This
equipment
has
been
type-tested
under standardized field
test
conditions
as
recommended
by
the Joint
Industry
Committee
on
High
Frequency
Stabilized
Arc
Welding
Machines
found
to
rad
late
less
than
10 microvolts
per
meter
at
a
distance
of
one
mile,
the
maximum allowable
limit
established
by
the
Federal
Communications Commission for
equipment
of
this
type.
Installations
using
this
equipment
on
the
basis
of
these
tests,
may
reasonably
be
expected
to
meet the
radiation limitations
established
by
the
Federal
Communications
Commission,
only
when
in
stalled,
operated
and maintained
as
specified
in
the
instruction
book
provided.
USERS
CERTIFICATION
The
welding
equipment
identified
above has
been
installed
in
accordance
with
the
specific
in
structions
applicable
to
this model
as
outlined in
the
instruction
book
furnished.
It
is
being
used
only
for
the
purpose
for
which
it
was
intended
and
is
being
maintained
and
operated
in
accord
ance
with the
manufacturers instructions.
Date
lnstallet

SECTION
1-SAFETY
RULES
FOR
OPERATION
OF
ARC
WELDING
POWER
SOURCE
1-1.
INTRODUCTION
We
learn
by experience.
Learning safety
through
personal
experience
like
achild
touching
ahot
stove
is
harmful,
waste
ful,
and unwise.
Let
the
experience
of
others teach
you.
Safe
practices
developed
from
experience
in
the
use
of
weld
ing
and
cutting
are
described
in
this
manual.
Research,
devel
opment,
and
field
experience
have
evolved
reliable
equipment
and safe
installation,
operation,
and
servicing
practices.
Acci
dents
occur
when
equipment
is
improperly
used
or
main
tained.
The
reason
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
attempting
to
install,
operate,
or
service
the
equipment.
Comply
with
these
procedures
as
applicable
to
the
particular
equipment
used
and
their instruction
manuals,
for
personal
safety
and
for
the
safety
of
others.
Failure
to
observe these
safe
practices
may
cause
serious
in
jury
or
death.
When
safety
becomes
a
habit,
the
equipment
can
be
used
with confidence.
Responsibilities
of
installer,
user,
and serviceman.
Installa
tion,
operation,
checking,
and
repair
of
this
equipment
must
be
done
only
by
a
competent
person,
experienced
with such
equipment.
These
safe
practices
are
divided into
two
Sections:
1
-
General
Precautions,
common
to
arc
welding
and
cutting;
and
2-
Arc
Welding
(and
Cutting)(only).
Reference standards:
Published Standards
on
safety
are
also
available for additional and
more
complete
procedures
than
those
given
in
this
manual.
They
are
listed
in
the
Standards
Index
in
these
safety
rules. ANSI
Z49.1
is the
most
complete.
The
National
Electrical
Code,
Occupation
Safety
and Health
Administration,
local
industrial
codes,
and
local
inspection
requirements
also
provide
a
basis
for
equipment
installation,
use,
and
service.
1-2.
GENERAL
PRECAUTIONS
A.
Burn
Prevention
Wear
protective
clothing
-
leather
(or asbestos)
gauntlet
gloves,
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
or
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.
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
persons
intending
to
weld
or
cut.
B.
Toxic
Fume
Prevention
Adequate
ventilation. 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 Stan
dard
Z49.1
listed
1
in
Standards
index.
NEVER
ventilate
with
oxygen.
Lead, cadium,
zinc,
mercury,
and
beryllium
bearing
and
simi
lar
materials,
when welded
(or
cut)
may
produce
harmful
concentrations
of
toxic
fumes.
Adequate
local
exhaust venti
lation
must
be
used,
or
each
person
in the
area
as
well
as
the
operator
must
wear an
air-supplied
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,
or
the
operator
wears
an
air-supplied
respirator.
Work
in
a
confined
space
only
while it is
being
ventilated
and,
if
necessary,
while
wearing
an
air-supplied
respirator.
Gas
leaks
in
a
confined
space
should be
avoided.
Leaked
gas
in
large
quantities
can
change
oxygen
concentration
danger
ously.
Do
not
bring
gas
cylinders
into
a
confined
space.
Leaving
confined
space,
shut
OFF
gas
supply
at
source.
The
space
will
then
be safe
to
re-enter,
if
downstream valves have
been
accidently
opened
or
left
open.
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
products.
The
ultra
violet
(radiant)
energy
of
the
arc
can
also
decompose
tn
chloroethylene
and
perchloroethylene
vapors
to
form
phos
gene.
DO
NOT
WELD
or
cut
where solvent
vapors
can
be
drawn into the
welding
or
cutting
atmosphere
or
where the
radiant
energy
can
penetrate
to
atmospheres
containing
even
minute
amounts
of
trichlorethylene
or
perchlorethylene.
C.
Fire and
Explosion
Prevention
Causes
of
fire
and
explosion
are:
combustibles
reached
by
the
arc,
flame,
flying
sparks,
hot
slag
or
heated
material;
misuse
of
compressed
gases
and
cylinders;
and short 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
electrical
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,
ventilators.
If the
work
can
not 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
ex
tinguishing
equipment
during
and for
some
time after
weld
ing
or
cutting
if:
a.
appreciable
combustibles
(including
building
construc
tion)
are
within
35
feet
b.
appreciable
combustibles
are
further
than
35
feet
but
can
be
ignited
by
sparks
c.
openings
(concealed
or
visible) in
floors
or
walls
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
pro
duce flammable
or
toxic
vapors
when
heated,
must
never
be
welded
on or
cut,
unless container
has
first been
cleaned
as
described
in
AWS
Standard
AGO,
listed
3
in
Standards
index.
OM-21
5
Page
1

This
includes:
a
thorough
steam
or
caustic
cleaning
(or
a
solvent
or
water
washing,
depending
on
the
combustibles
solubility(
followed
by
purging
and
inerting
with
nitrogen
or
carbon
dioxide,
and
using
protective
equipment
as
recom
mended
in
A6.O.
Waterfilling
just
below
working
level
may
substitute
for
inerting.
A
container
with
unknown
contents should
be
cleaned
(see
paragraph
above).
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
gaso
line).
D.
Compressed
Gas
Equipment
Standard
precautions.
Comply
with
precautions
in
this
manual,
and
those
detailed
in
CGA
Standard
P-i,
PRECAU
TIONS
FOR SAFE
HANDLING OF
COMPRESSED
GASES
IN
CYLINDERS,
listed 6
in
Standards
index.
1.
Pressure
Regulators
Regulator
relief
valve is
designed
to
protect
only
the
regula
tor
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
repair
(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
pointer
does
not
move
off
stop pin
when
pressurized,
nor
returns to
stop pin
after
pressure
release.
Repair.
Do NOT
attempt
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
accident.
(See
1
-3C.
ICC
or
DOT
marking
must
be
on
each
cylinder.
It is
an
assurance
of
safety
when
the
cylinder
is
properly
handled.
Identifying
gas
content
Use
only
cylinders
with
name
of
gas
marked
on them;
do
not
rely
on
color
to
identify
gas
con
tent.
Notify
supplier
if
unmarked.
NEVER DEFACE
or
alter
name,
number,
or
other
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.
Prohibited
use.
Never
use
a
cylinder
or
its
contents
for other
than its
intended
use,
NEVER
as
a
support
or
roller.
Secure
from
falling.
Chain
or
secure
cylinders
upright
when
a
regulator
(and hose)
are
connected to
it.
Passageways
and
work
areas.
Keep cylinders
clear
of
areas
where
they
may
be struck.
Transporting
cylinders.
With
a
crane,
use
a
secure
support
such
as
a
platfonn
or
cradle.
Do
NOT
lift
cylinders
off the
ground
by
their
valves
or
caps,
or
by
chains,
slings,
or
mag
nets.
Do NOT
expose
cylinders
to
excessive
heat,
sparks,
slag,
and
flame,
etc.
that
may
cause
rupture.
Do not allow 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
or
metal
wrench
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 other
the.i
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
ordinary
wire
or
other
substitute)
as
a
binding
to connect
hoses
to
fittings.
No
copper
tubing splices.
Use
only
standard
brass
fittings
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
other
wise
damaged.
Coil
excess
hose
to
prevent
kinks
and
tangles.
Protect
hose
from
damage
by
sham
edges,
and
by
sparks,
slag,
and
open
flame.
Examine
hose
regularly
for
leaks,
wear,
and
loose
connec
tions. Immerse
pressured
hose
in
water;
bubbles
indicate
leaks.
Repair
leaky
or
worn
hose
by
cutting
area
out
and
splicing
(1-2D3).
Do
NOT
use
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
people
and
sources
of
ignition.
Wipe
with
a
clean lint-
less
cloth.
Match
regulator
to
cylinder.
Before
connecting,
check
that
the
regulator
label and
cylinder
marking
agree,
and
that the
regulator
inlet
and
cylinder
outlet
match.
NEVER
CON
NECT
a
regulator
designed
for
a
particular
gas
or
gases
to
a
cylindercontaining
any
other
gas.
Tighten
connections.
When
assembling
threaded
connections,
clean
and
smooth
seats
where
necessary.
Tighten.
If
connec
tion
leaks, disassemble,
clean,
and
retighten.
For
metal-to-
metal
seating,
use
correct
wrenches,
available
from
your
supplier.
For
0-ring
connections,
hand
tighten.
Adapters.
Use
a
CGA
adapter
(available
from
your
supplier)
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
before
opening
cylinder
(or
manifold
valve)
by
turning
adjusting
screw
in
(clockwise).
Draining
prevents
excessive
compression
heat
at
high
pressure
seat
by
allowing
seat to
open
on
pressur
ization. Leave
adjusting
screw
engaged
slightly
on
single-stage
regulators.
Before
opening
clinder
valve,
check that
hoses
are
con
nected and
that
downstream
valves
are
closed.
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
regu
lator maximum)
leave
cylinder
valve
in
following
position:
For
oxygen,
and inert
gases,
open
fully
to
seal
stem
against
Page
2

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.
It
will
reduce
backfiring
and
chance
of
flashbacks.
Check
for
leaks
on
first
pressurization
and
regularly
there
after.
Brush
with
so~
solution
(capful
of
Ivory
Liquid*
or
equivalent
per
gallon
of
water).
Bubbles indicate leak.
Clean
off
soapy
water
after
test;
dried
soap
is
combustible.
E.
User
Responsibilities
Remove
leaky
or
defective
equipment
from
service
immed
iately
and
repair
them
only
if
recommended
in
equipment
instruction
manual.
Send
others
for
repair
to
manufacturers
designated
repair
Center
where
special techniques
and
tools
are
used
by
trained
personnel.
Refer
to User
Responsibilities
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
cut
ting operation;
rope
may
burn.
1-3.
ARC WELDING
Comply
with
precautions
in
1-2
and
this
section.
Arc
Weld
ing, properly
done,
is
a
safe
process,
but
a
careless
operator
invites trouble. The
equipment
carries
high
currents
at
signifi.
cant
voltages.
The
arc
is
very
bright
and hot.
Sparks
fly,
fumes
rise,
ultraviolet
and
infrared
energy
radiates,
weld
menis
are
hot,
and
compressed
gases
may
be used.
The
wise
operator
avoids
unnecessary
risks
and
protects
himself
and
others from
accidents. Precautions
are
described here
and
in
standards
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;
COMPLY
WITH
PRECAUTIONS.
1.
Protective
Clothing
Wear
long-sleeve clothing
(particularly
for
gas-shielded
arc)
in
addition
to
gloves,
hat,
and shoes
ll-2A).
As
necessary,
use
additional
protective
clothing
such
as
leather
jacket
or
sleeves,
flame-proof
apron,
and
fire-resistant
leggings.
Avoid
outergarments
of untreated
cotton.
Bare
skin
protection.
Wear
dark,
substantial
clothing.
Button
collar
to
protect
chest
and
neck
and
button
pockets
to
pre
vent
entry
of
sparks.
2.
Eye
and
Head
Protection
Protect
eyes
from
exposure
to
arc.
NEVER
look
at
an
elec
tric
arc
without
protection.
Welding
helmet
or
shield
containing
a
filter
plate
shade
no.9
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
IM
MEDIATELY.
Replace
clear
cover
plate
when
broken,
pitted.
or
spattered.
Flash
goggles
with
side
shields
MUST
be
worn
under
the
helmet
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 burn
that
may
leave
a
permanent
dark
area
in
the
field
of
vision.
3.
Protection
of
Nearby
Personnel
Enclosed
welding
area.
For
production welding,
a
separate
room
or
enclosed
bay
is
best.
In
open
areas,
surround
the
operation
with
low-reflective,
non-combustible
screens
or
panels.
Allow
for
free
air
circulation,
particularly
at
floor
level.
Viewing
the
weld. Provide face shields for
all
persons
who
will be
looking
directly
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
fire.
Never
strike
an
arc
on a
cylinder
or
other
pressure
vessel,
It
creates a
brittle
area
that
can cause a
violent
rupture
or
lead
to
such
a
rupture
later 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
welding
circuit,
or
in
ungrounded,
electrically-HOT equipment
can
fatally
shock
a
person
whose
body
becomes
a
conductor.
DO
NOT
STAND,
SIT,
LIE,
LEAN
ON,
OR
TOUCH
a
wet
sur
face
when
welding,
without
suitable
protection.
To
protect
against
shock:
Keep
body
and
clothing
dry.
Never
work
in
damp
area
with
out
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 between
body
and
an
electrically
HOT
part
-
or
grounded
metal
-
reduces
the
body
surface electrical
resistance,
enabling
dangerous
and
possibly
lethal currents to
flow
through
the
body.
1.
Grounding
the
Equipment
When
installing,
connect
the
frames
of
each unit
such
as
welding
power
source,
control,
work
table,
and
water
circula
tor
to
the
building
ground.
Conductors
must
be
adequate
to
carry
ground
currents
safely.
Equipment
made
electrically
HOT
by stray
current
may
shock,
possibly
fatally.
Do
NOT
GROUND
to
electrical
conduit,
or
to
a
pipe
carrying
ANY
gas
or
a
flammable
liquid
such as
oil
or
fuel.
Three-phase
connection.
Check
phase
requirement
of
equip
ment
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
equipment
ground
lead
to
the third
(live)
wire,
or
the
equipment
will
become
electri
cally
HOT
-
a
dangerous
condition
that
can
shock,
possibly
fatally.
Before
welding,
check
ground
for
continuity.
Be
sure
conduc
tors
are
touching
bare
metal
of
equipment
frames
at
connec
tions.
If
a
line
cord with
a
ground
lead
is
provided
with
the
equip
ment
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
receptacle,
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.
Trademark
of
Proctor
& Gamble.
OM-215
Page
3

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
for
wear,
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
Terminals
and other
exposed
parts
of
electrical
units
should
have
insulating
covers
secured before
operation.
6.
Electrode Wire
Electrode
wire becomes
electrically
HOT
when the
power
switch of
gas
metal-arc
welding
equipment
is
ON
and
welding
gun
trigger
is
pressed. Keep
hands
and
body
clear of
wire
and
other
HOT
parts.
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-t~
switches)
to
prevent
accidental
turning
ON
of
power.
Discon
nect
all
cables from
welding
power
source,
and
pull
all
115
volts
line-cord
plu~.
Do
not
open power
circuit
or
change
polarity
while
welding.
If,
in
an
emergency,
it
must
be
disconnected,
guard
against
shock
burns,
or
flash from switch
arcing.
Leaving
equipment
unattended.
Always
shut
OFF
and
dis.
connect
all
power
to
equipment.
Power
disconnect
switch
must
be available
near
the
welding
power
source.
1-4.
STANDARDS
BOOKLET INDEX
For
more
information,
refer
to
the
following
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,
2501 NW 7th
St., Miami,
Fla. J3125.
2.
ANSI
Standard
Z87.1,
SAFE
PRACTICE
FOR
OCCUPA
TION
AND
EDUCATIONAL
EYE AND
FACE
PROTEC.
TION,
obtainable
from
American National Standards
Institute,
1430
Broadway,
New
York,
N.Y.
10018.
3.
American
Welding Society
Standard
A6.0,
WELDING
AND
CUTTING CONTAINERS
WHICH HAVE HELD
COMBUSTIBLES,
obtainable
same as
item
1.
4. NFPA
Standard
51.
OXYGEN-FUEL
GAS
SYSTEMS
FOR WELDING
AND
CUTTING,
obtainable from
the
National
Fire Protection
Association,
470
Atlantic
Avenue. Boston.
Mass.
02210.
5.
NFPA
Standard
518.
CUTTING AND WELDING
PRO
CESSES,
obtainable
same
as
item 4.
6.
CGA
Pamphlet
P-i. SAFE HANDLING OF COM
PRESSED GASES IN
CYLINDERS,
obtainable
from the
Compressed
Gas
Association,
500 Fifth
Avenue,
New
York,
N. V.
10036.
7. OSHA
Standard 29
CFR,
Part
1910,
Subpart
0,
WELD
ING,
CUTTING AND BRAZING.
Page
4

SECTION
2-
INTRODUCTION
Rated
Welding
Current
Amperes
Welding
Current
Range
Amperes
Max.
Open-
Circuit
Voltage
Amper~s Input
At
Rated Load
Output
60
Hz Three-Phase

kw
Overall
Dimensions
(Inches)
Weight
(Pounds)
Net
Ship
200(208) Volts
230
Volts 460
Volts kva
300 @
15
Volts
100%
Duty Cycle
3-300 85
121
115 57
45.9
11.5
Height-
38-1/2
Width
-23-1/2
Depth
-42
800
900
2-1.
GENERAL
Figure
2-1.
Specifications
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.
2-2.
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.
2-3. DESCRIPTION
This unit is
a
constant
current
welding
power
source
which
requires
three-phase
60
Hz.
electrical
power
for
operation.
This
welding
power
source
is
intended
to
be
used
in
conjunc
tion with the
Gas
Tungsten-Arc
(TIG)
Welding
process.
I
2-4.
SAFETY
Before
the
equipment
is
put
into
operation,
the
safety
sec
tion
at
the
front
of
this
manual
should
be read
completely.
I
I
Under
this
heading, explanatory
statements
will
be
found that need
special
emphasis
to
obtain
the
most
efficient
operation
of
the
equipment.
I
I
3-1.
LOCATION
(Figure
3-1)
A
proper
installation
site should
be selected
for
the
welding
power
source
if
the
unit
is
to
provide
dependable
service,
and
remain
relatively
maintenance
free.
A
proper
installation
site
permits
freedom of
air
movement
into
and
out
of
the
welding
power
source,
and
also least
subjects
the unit
to
dust,
dirt, moisture,
and
corrosive
vapors.
A minimum of
18
inches of
unrestricted
space
must
be
main
tained
between the
welding
power
source
front
and
rear
panels
and the
nearest
obstruction.
Also,
the
underside of
the
welding
power
source
must
be
kept completely
free
of
obstructions.
The
installation site should
also
permit
easy
removal of the
welding
power
source
outer enclosure for
maintenance functions.
place
an
jir
ove
r
the
in
to
ke
air
passages
of
the
welding
power
source as
this
would
restrict the
volume of intake
air
and
thereby
subject
the
welding
power
source
internal
components
to
an
overheating
condition
and
subsequent
failure,
War

ronty
is
void
if
any
type
of
filtering
device is
used
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:
CAUTION
Under this
heading,
installation,
opera~~g,
and
main
tenance
procedures
or
practices
will be
found that
if
not
carefully
followed
may
create
a
safety
hazard
to
personnel.
~TAN~~~
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
SECTION
3
-
INSTALLATION
Holes
are
provided
in
the
welding
power
source
base
for
mounting
purposes.
Figure
3-1
gives
overall
dimensions
and
the
base
mounting
hole
layout.
Figure
3-1. Dimensional
Drawing
TA-901
094-1
OM-21
5
Page
5

On
most
welding
power
sources
a
lifting
device
is
provided
for
moving
the
unit.
However,
if
a
fork
lift
vehicle
is
used
for
lifting
the
unit,
be
sure
that the
lift
forks
are
long
enough
to
extend
completely
under the base.
IMPORT
The
use
of lift
forks
too
short
to
extend
Out of
the
opposite
side of
the
base
will
expose
internal
com
ponents
to
damage
should the
tips
of the lift
forks

penetrate
the
bottom
of
the unit.
3-2.
ELECTRICAL INPUT
CONNECTIONS
E~J
It is recommended
that
a
Line
Disconnect
Switch
be
installed
in
the
input
circuit
to
the
welding
power
source.
This
would
provide
a
safe and
convenient
means
to
completely
remove
all
electrical
power
from
the
welding
power
source
whenever
it
is
necessary
to

perform
any
internal function
on
the
unit
CAUTION
I
Before
making
electrical
input
conons
to
the
welding
power
source.
machinery
lockout
proce
dures
should
be
employed.
If
the connection is
to be
made
from
a
line
disconnect
switch,
the switch
should
be
padlocked
in
the
open
position.
If
the connection
is
made
from
a
fuse
box,
remove
the
fuses
from the
box
and
padlock
the
cover
in the
closed
position.
If
lock
ing
facilities
are
not
available,
attach
a
red
tag
to
the
line disconnect switch (or
fuse
box)
to
warn
others
that
the circuit is
being
worked
on.
A.
Input
Electrical
Requirements
This
welding
power
source
is
designed
to
be
operated
from
a
three
phase,
60
Hertz,
ac
powei-
supply
which
has
a
line
voltage
rating
that
corresponds
with
one
of
the
primary
volt
ages
shown
on
the
welding
power
source
nameplate.
Consult
the local electric
utility
if
there
is
any
question
about
the
type
of
electrical
system
available
at
the installation site
or
how
proper
connections
to
the
welding
power
source are
to
be made.
NOTE
It is
recommended that
a
terminal
lug
of
adequate
amperage
capacity
be attached
to
the
ends
of
the
input
and
ground
conductors. The hole
diameter
in
the terminal
lug
must
be
of
proper
size
to
accommo
date the
line
and
ground
terminal
studs
on
the
primary

terminal
board.
Connect
the
three
input
conductors
to
the terminals
on
the
primary
terminal
board
labeled
L
or
LINE and
connect
the
ground
conductor
to
the terminal
labeled GAD
(See
Figure
3-2).
The
remaining
end
of
the
ground
conductor
should
be
connected
to
a
proper
ground.
Use
whatever
grounding
method that
is
acceptable
to
the
local
electrical
inspection
authority.
CAUTION_j
I
The
terminal
labeled GRD
is
con
nected to
the
welding
power
source
chassis
and is for
grounding
purposes
only.
Do
not connect
a
conductor from
the terminal
labeled GAD
to
any
one
of the
L
or
LINE
terminals
as
this
will
result in
an
electrically
hot
welding
power
source
chassis.
B.
Input
Conductor Connections
CAUTION

Do
not
connect
the
input
conducto~he
three-
phase
power
supply
until all
input
electrical
connec
L
tions
have
been
made
to
the
welding
power
source
The
input
conductors
should
be covered
with
an
insulating
material
which conforms
to local electrical standards.
Table
3-1
is
provided
only
as a
guide
for
selecting
the
proper
size
input
conductors
and
fuses.
Table
3-1.
Input
Conductor
and
Fuse Size
Input
Conductor Size
-
AWG
Fuse
Size
In
Amperes
200(208)V
230V 460V
200V
230V
460V
1
2
6
(6) (6)
(8)
200
175
90
Numbers
in C
C
indicate
ground
conductor
size.
Insert
the three
input
conductors
plus
one
ground
conductor
through
the
access
hole
on
the
rear
panel.
This hole will
accept
standard conduit
fittings.
See
Figure
3-2 for hole
loca
tion
and
size.
C.
Matching
The
Welding
Power Source To
The
Avail
able
Input Voltage
The
input voltage
jumper
links
provided
on
the
primary
ter
minal
board
permit
the
welding
power
source
to
be
operated
from
various
line
voltages.
The
various
voltages
from which
this
welding
power
source
may
be
operated
are
stated
on
the
welding
power
source
nameplate,
and
on
the
input
voltage
label.
See
Figure
3-2
for
location.
The
input voltage
jumper
links
on
this
welding
power
source
are
positioned
for the
highest
of
the
voltages
stated
on
the
nameplate.
If
the weld
ing
power
source
is
to be
operated
from
a
line
voltage
which
is
lower
than
the
highest
voltage
for
which the
unit
was
de
signed,
the
jumper
links will have
to
be
moved
to
the
proper
position
before
operation
of
the
welding
power
source com
mences.
Figure
3-3
shows the
various
positions
for
which
the
jumper
links
may
be
set
on
the
standard
welding
power
source.
If
the
input
voltages
on
the
welding
power
source
nameplate
differ
from those
shown
in
Figure
3-3,
the
input
voltage
jumper
links
must be
positioned
as
shown
on
the in
put
voltage
label.
one
j
u
mper
link
req
uired
on
ea
ch
of
t
he
grouped
terminals,
it is
recommended that the unused
jumper
links
be
placed
across
the
terminals
which
are
to
be used. This
will
prevent
losing
the
jumper
links
which
are
not
required
for this
connection.
Line
Input
Voltage
Jumper
Links
Ground
Terminal
TB-000
600
Figure
3-2.
Input
Conductor
Connections
Page
6

0
0 0 0
0 0
0 0 0 0
00
460
Volts
~
'L~
~L2
'L3fl~fl
TA-901
094-6
Figure
3-3.
Input
Voltage
Jumper
Link
Arrangement
3-
3.
SECONDARY
WELDING
CONNECTIONS
It
is recommended that
the
welding
cables be
kept
as
short
as
possible,
be
placed
close
together,
and be
of
adequate
current
carrying
capacity.
The resistance
of the
weldIng
cables and
connections
cause a
voltage
drop
which is
added to
the volt
age
of
the
arc.
Excessive cable
resistance
may
result in
over
loading
as
well
as
reducing
the maximum
current
output
of
which
the
welding
power
source
is
capable.
The
proper
opera
tion
of
any welding
power
source
is
to
a
great
extent
depen
dent
on
the
use
of
welding
cables and connections
that
are
in
good
condition and of
adequate
size. An
insulated
electrode
holder
must be
used
to
ensure
the
operators safety.
Use Table
3-2
as a
guide
for
selecting
the
correct
welding
cable
size
for
the
anticipated
maximum weld
current
that
will
be
used.
Table 3-2
takes
into
account
the
total
cable
length
for
the weld
circuit.
This
means
the
length
of
the
Electrode
cable
that
connects
the
Electrode
Holder
to
the
welding
power
source
and
the
Work
or
ground
cable between
the
welding
power
source
and
the
workpiece.
For
example:
If
the
Electrode
cable
is
75 feet
long
and the
Work
or
ground
cable
is
25 feet
long,
select
the
size cable from
Table
3-2 that
is
recommended for
100
feet
at
the
maximum
amperage
that
will
be used..
For
example,
in
a
100
foot weld circuit
where
a
maximum
weld
current
of
150
amperes
is
anticipated,
No.
2
weld
cable would
be
recommended for
both
the
Electrode
and
Work
cables.
If
reverse
polarity
is
to
be
used for the
welding
operation,
connect
the electrode holder cable
to
the
WORK
secondary
terminal and the
work cable
to
the
ELECTRODE
secondary
terminal.
To
obtain
straight polarity,
connect
the
electrode
holder cable
to
the
ELECTRODE
secondary
terminal and
the
work cable
to
the
WORK
secondary
terminal.
Table 3-2.
Secondary
Cable Sizes
WELDING
TOTAL LENGTH
OF
CABLE
(COPPERI
IN
WELD
CIRCUIT
AMPERES
50 100 150 200
250 300 350
400
100
150
200
250
300
4 4
2 2
1
1
1/0 1/0
2/0 2/0
2 2 2
1
1/0
1)0
2
1
1/0
2/0
3/0 3/0
1
1/0
2/0
3/0
4/0
4/0
1/0
210 3/0 4/0 4/0
2-2/0
2/0
3/0 4/0
4/0
22/0
2-3/0
A-002 623
NOTE:
A.
50
FEET OR
LESS.
B.
CABLE
SIZE
IS
BASED
ON DIRECT
CURRENT
IDC),
100% DUTY
CYCLE
AND EITHER
A
4
VOLTS
OR
LESS
DROP
OR
A
CURRENT
DENSITY OF
NOT
OVER
300
CIRCULAR MILS
PER AMP.
C. WELD
CABLE
INSULATION
WITH A
VOLTAGE
RATING
TO
WITHSTAND
THE
OPEN-CIRCUIT
VOLT
AGE
IOCVI
OF
THE
WELDING POWER
SOURCE
MUST
BE
USED.
WHILE
MOST WELDING
POWER
SOURCES
HAVE AN
OPEN-CIRCUIT
VOLTAGE OF
LESS
THAN
100
VOLTS,
SOME
WELDING POWER
SOURCES
OF
SPECIAL DESIGN
MAY
HAVE
HIGHER
OPENCIRCUIT
VOLTAGE.
3-4.
REMOTE
CURRENT CONTROL CONNECTIONS
(Figure
3-4)
The CURRENT
CONTROL
Receptacle,
located
on
the lower
front
panel
of
the
welding
power source,
provides
a
junction
point
for
connecting
a
Remote Current
Control to
the
cur
rent
control
circuitry
within
the
welding power
source.
To
connect
the
Remote
Current
Control
to
the
CURRENT
CONTROL
Receptacle,
insert the
three-prong plug
from
the
Remote Current
Control
into the
receptacle.
Rotate
the
plug
clockwise
as
far
as
possible, thereby
locking
the
plug
in
the
receptacle.
3-5. CONTACTOR
(START)
CONTROL
CONNECTIONS
(Figure
3-4)
The
CONTACTOR CONTROL
Receptacle provides
a
junc
tion
point
for
connecting
a
Remote
Contactor
Control
device
to
the
contactor
control
circuitry
in
the
welding
power
source.
To
Connect
the
Remote Contactor Control to
the CON
TACTOR CONTROL
Receptacle,
insert
the
two-prong
plug
from
the
Remote
Contactor
Control
device
into the
CON
TACTOR
CONTROL
Receptacle
and
rotate
the
plug
as
far
as
it will
turn
in
a
clockwise
direction. The
plug
will
now
be
locked
in
the
receptacle
and
will
not
pull
out
under
stress.
Remote
contactor
control
can
also
be
achieved
by
connecting
the
two
leads
from
the
Remote
Contactor
Control
to
ter
minals
160
and
113 of
terminal
strip
2T.
A.
Remote
Stop
Switch
(Electroslope
Models
Only)
A
normally-closed,
momentary
contact
Remote
Stop
Switch
(not
supplied)
will have
to
be connected
to
terminals 1
and
122 of
terminal
strip
2T
in
order
to
have
a
device
available
which
can
cut
off weld
current
when
in the
GTAW
AUTO
mode.
NOTE
When
using
a
Remote
Stop
Switch
it will
be
necessary
to
remove
the
jumper
link
which
is
connected
between
terminals 2T1
and
2T122.
Other
than
placing
the
POWER
Switch
in
the
OFF
position
when
in
the
GTAW
AUTO
mode,
there will be
no means
available
for
shutting
off
the weld
current
if
a
Remote
Stop
Switch is
not
connected
to
terminals 2T1 and
2T122.
3-6. UPSLOPE &
DOWNSLOPE
CONNECTIONS
(Elec
troslope
Models
Only)
-
Local
or
remote
manual initiation
of
upslope
or
downslope
should
not be used
when
the
FUNCTION
Switch
is
in
the
GTAW
MANUAL
position.
If local
or
remote
manual
initia
tion
of
upslope
or
downslope
Is
desired
the
FUNCTION
Switch should be
placed
In
the
GTAW AUTO
position.
When
in
the
GTAW AUTO
position,
either the
local
slope
control
push-button
switches
on
the
front
panel
or
a
Remote
Slope
Switch
(not
supplied)
can
be used for
upslope
or
downslope
initiation.
For
remote
slope
control
capability,
connect
a
single-pole,
double-throw,
momentary-contact,
center-off
switch
to terminal
strip
2T.
Connect
a
lead
from
the
center
terminal of the Remote
Slope
Switch
to
terminal
2T1 20.
Connect
a
lead
from the
upslope
terminal
of
the
switch
to
terminal
2T72.
Connect
a
lead from
the
downslope
terminal
of
the switch
to
terminal
2T107. The
detailed
operation
of
the
slope
control
switches
will
be
explained
in
Section
4.
If it is desired
to
bypass
the initial
current
portion
of the
weld
cycle
and
go
directly
into
upslope
upon
arc
initiation,
do
not Connect
a
lead
from
the
upslope
terminal
on
the
Remote
Slope
Switch
to
terminal
2T72.
Rather
Connect 8
jumper
link
between terminals
2T1 20
and
2T72.
3-7.
WATER VALVE
CONNECTIONS
(Figure
3-4)
A
valve
is
provided
in
order to control
on
and
off
flow of
coolant water
to
the
electrode holder.
The
WATER
valve
input
and
output
connections
both
have left-hand
threading.
Ensure
that
the
hose
from
the
water
source
is
attached to
the
~00~
~OO~ ~O0~
208
V
GR.
'L1
'L2
__
O~0
0~O.0~I~O
230 Volts
&
'L1 ~L2
'
L3
LJt0101O]~LJ
OM-215
Page
7

connection
on
the WATER
valve
labeled
IN.
The
water
hose
from
the
electrode
holder
must
be
attached to the
connec
tion
on
the
WATER
valve
labeled OUT.
flRTA~~
If
a
Coolant
Pump
is
to
be used and
the
Coolant
Pump
is
not
equipped
with
a
by-pass
network,
do
not
make
Connections
from
the
Coolant
Pump
to
the
WATER
valve
but
rather
connect
the
Coolant
Pump
directly
to
the electrode
holder
water
hoses.
Failure
to
comply
may
result in
damage
to
the
Coolant
Pump
due
to
excessive
back
pressure
when the
WATER
valve is
closed.
-
-- -~
3-8.
SHIELDING
GAS
VALVE
CONNECTIONS
(Figure
3-4)
A
valve
is
provided
in
order
to
control
on
and
off
flow
of
shielding
gas
to
the
electrode holder.
The
GAS
valve
input
and
output
connections both have
right-hand
threading.
Ensure
that the hose
from
the
shielding
gas
source
is attached
to
the connection
on
the
GAS
valve labeled
IN. The
shielding
gas
hose from the electrode holder
must
be attached
to
the
connection
on
the
GAS
valve
labeled
OUT.
TA-901 094-2
SECTION
4-
FUNCTION
OF
CONTROLS
NOTE
4-2.
WELD/BACKGROUND
CURRENT
CONTROL
(Fig
ures
4-1,4-2.
&
4-3)
The data contained
within
headings
4-1
through
4-8
applies
to
all
models
covered
in this
manual.
Placing
the
POWER
Switch
in
the
ON
position
will
energize
the
welding
power
source
fan
and control
circuitry
and
place
the
welding
power
source
in
a
ready-to-weld
status.
The
pilot
light
on
the
front
panel
will be
illuminated
when the
POWER
Switch
is
in
the
ON
position.
Placing
the
POWER
Switch
in
the
OFF
position
will shut
the
welding
power
source
down.
Even
though
the
POWER
Switch
is
in
the
OFF
posi
tion and the
welding
power
source
is
apparently
elec
trically
shut
down,
electrical
input
power
is still
pre
sent
on
all
circuitry
up
to
the
POWER
Switch. To
completely
cut-off
all
electrical
input
power
to
the
welding
power source,
it
will
be
necessary
to
place
the
line disconnect switch
in the
OFF
position
or remove
the electrical
input
fuses.
On
the
model with
only electroslope
control and the
models
with
pulser
control when the
pulse
capability
is
not
being
utilized,
the
WELD/BACKGROUND
CURRENT
Control
provides
a
means
of
selecting
the
desired
current
output
with
in the
entire
current
range
of
the
welding
power
source.
The
center
portion
of
the
WELD/BACKGROUND
CURRENT
Control
has
a
three-digit
numeric
display
which
registers
the
current selected.
Rotating
the
outer
collar of the
WELD/
BACKGROUND
CURRENT
Control
in
a
clockwise
direction
will
increase
the
current
output.
U
I
The
WELD/BACKGROUND
CURRENT Control
may
be
adjusted
while
welding
(under
load
conditions).
On
models with
pulser
capability
when
the
pulse
controls
are
being
utilized,
the
WELD/BACKGROUND
CURRENT
Con
trol determines
the level
which
the
weld
current
is
at
when it
goes
to
the
setting
of
the
PEAK
CURRENT Control. This
current
level will be the
same
level
to
which
the
weld current
will
return
once
it leaves the
setting
of the
PEAK CURRENT
Control.
When
this
current
level
is discussed
hereafter
in
this
manual,
it will be referred
to
as
the
background
current
level.
Figure
3-4.
Lower
Front
Panel
Component
Location
I
I
4-
1.
POWER
SWITCH
(Figures
4-1, 4-2,
&
4-3)
U
I
I
Page
8

Figure
4-2.
Control Panel View For Models With
Electroslope
Controls
Only
Figure
4-3. Control
Panel
View
For
Models
With
Electroslope
&
Pulser Controls
TA-901 410-1
TA-901
417-2
TA-901
417-2
Figure
4-1. Control
Panel
View
For
Model With
Pulser
Controls
Only
OM-215
Page
9

4-3.
CURRENT
CONTROL
RECEPTACLE
&
SWITCH
(Figure
3-4)
If
a
Remote
Current
Control
is
to be
used,
make
connections
from the
Remote
Current
Control
to
the CURRENT
CON
TROL
Receptacle
as
instructed
by
the
data
contained
within
heading
3-4.
When
remote
control of the
current
is
desired,
it is
essential
that the
CURRENT CONTROL
Switch
be
placed
in
the
REMOTE
position.
Likewise,
if
a
Remote
Current
Control
is
not to be
utilized,
the
switch
must
be
in the
STANDARD
position.
When
in
the
STANDARD
position,
only
the
WELD/BACKGROUND
CURRENT Control
on
the
front
panel
will control the
current.
When
a
Remote
Current Control
is
being
used,
it
should
be
noted
that
the
Remote Current Control
is
functioning
as
a
fine
current
adjustment
for
the
WELD/BACKGROUND
CURRENT
Control
setting
on
the
welding
power
source.
For
example:
If
the
WELD/BACKGROUND
CURRENT Control
on
the
welding
power
source
is
set
at
the
150
position,
the
Remote
Current Control
will
provide
(from its mm.
to
max.
positions)
fine
amperage
adjustment
of one-half of the
weld
ing
power
source
output
for
the
current
range
selected.
If full
adjustment through
use
of the
Remote
Current Control
is
desired,
the
WELD/BACKGROUND
CURRENT Control on
the
welding
power
source
must be
set at
the
300
position.
4-4. STARTING CURRENT SELECTOR SWITCH
(Fig
ures
4-1,
4-2,
&
4-3)
In addition to
the
HIGH-FREQUENCY
Switch,
there
is
an
independent
STARTING CURRENT SELECTOR Switch
on
the
front
panel.
It is
a
three-position
toggle
switch
which
should
be set
according
to
conditions
at
the
torch.
The
OFF
and
1
positions
are
generally
used
with
small diameter elec
trodes,
and
the
2
position
with
large
diameter
electrodes.
The
functions
of the three
positions
are as
follows:
1.
OFF

Recommended for
argon gas
and all size
elec
trodes. In this
position
the
high-frequency
(if
turned on)
ignites
the
arc
at
the
initial
current
setting.
No
additional
starting
pulse
is
provided.
2.
No
1

Recommended for
argon
or
helium and
.010
inch
through
.040
inch diameter electrodes.
Provides a
25
ampere
pulse
of
start current
for
1/6
second
(10
cycles).
3.
No. 2

Recommended
for helium and
1/16
inch
dia
meter
and
larger
electrodes. Provides
a
50
ampere
pulse
of
start
current
for
1/6
second
(10
cycles).
In
this
position
the normal
3
ampere
minimum
current
of
the
welding
power
source
is raised
to
25
amperes
so as
to
adequately
sustain
the
arc
with
larger
electrodes.
4-5.
CONTACTOR
CONTROL RECEPTACLE
Closing
the
Remote Contactor Control Switch
on
the
model
with
only pulse
control
and the
models with
electroslope
control
when the
Function Switch
is in
the
GTAW MANUAL
position,
provides
weld
current
and
high-frequency,
and
energizes
the
GAS
and
WATER Valves.
All of
these
items
remain active
(high-frequency
remains
on
until
an
arc
is
established
only
if
the
HIGH-FREQUENCY
Switch
is
in
the
START
position)
for
as
long
as
the
Remote Contactor
Con
trol
Switch
is closed.
Opening
the
Remote
Contactor
Control
Switch
will shutoff the
weld
Current
and
start
the
POST-
FLOW
Timer.
On
the
models
with
electroslope
control when the
Function
Switch
is in the
GTAW
AUTO
position, momentarily
closing
the
Remote Contactor Control Switch
provides
weld
current
at
the
initial
current
level.
Also,
high-frequency
will
be
pre
sent
during
arc
initiation
if the
HIGH-FREQUENCY Switch
is in the
START
position
and the
GAS
and WATER
Valves
will be
energized.
4-
6.
HIGH-FREQUENCY SWITCH
(Figure
3-4)
A.
Start Position
When
in
the
START
position,
high-frequency
is
present
at
the
welding
electrode
from
the
time
the
contactor
is
closed
until the
arc
is
initiated.
Once
an arc
is
established,
and
even
though
the
contactor
is
closed,
the
high-frequency
will
be
de-energized.
High-frequency
will
be
present again
only
after
the
arc
is
broken
and
restarted.
B.
Off
Position
High-frequency
will
not
be
available
when in
the
OFF
posi
tion,
even
if the
contactor
is closed.
4-
7.
POST-FLOW
TIMER
(Figure
3-4)
An
adjustable
0
to 60 second
POST-FLOW
Timer
is
provided
for
controlling
the
period
of
time
shielding
gas
and
water
(coolant) will be allowed
to
flow after the
arc
is
extinguished.
To select
the
desired
portion
of the
maximum
60
second
post-flow
time
period available,
rotate
the
adjustable
stop
arm on
the timer until the
appropriate
setti~~g
is obtained.
As
soon as
the
arc
has
been
extinguished,
the
POST-FLOW
Timer
will
begin
to
time
out
the
selected
period
of
post-flow
time.
Once
the
selected
post-flow
time
has
elapsed,
the
GAS
and
WATER
Valves
close and
thereby
Cut
of
f
shielding
gas
and coolant flow.
The
timer will then
automatically
reset
and
be
ready
for another
weld
cycle.
4-8. METERS
(Figure
4-1)
This
welding
power
source
is
equipped
with
a
dc
ammeter
and
a
dc
voltmeter.
These
meters
are
internally
connected
to
the
welding
power
source
output
welding
terminals.
The
volt
meter
will indicate
the
dc
voltage
at
the
terminals,
but does
not
necessarily
indicate
the
actual
voltage
at
the
welding
arc.
If
the
welding
cables
are
excessively
long
or
have
poor,
loose
connections,
the
difference
between actual
arc
voltage
and
the
voltage
at
the
welding
power
source
terminals
may
be
considerable. For
best results
always keep
the
welding
cables
short
and
of
ample
size
to
carry
the
welding
current.
All
Connections in
the
welding
Circuit
should
be
clean
and
tight
and
under
no
circumstances should the
welding
current
be
conducted
through
a
bearing
of
any
type.
The
panel
ammeter
included with this
welding
power
source
is
a
–
2
per
cent
(full scale) instrument.
This
is
the
meter
manufacturers
guarantee.
In
practice,
and
when
new,
the
meter
is
generally
considerably
more
accurate.
Nonetheless,
if
welding
(or
setting
up)
at
the
low
current
end,
at
10
amperes
for
instance,
the
meter
reading
could be
as
much
as
6
amps
off either
way.
(2
per
cent
of
300
amps)
The
digital
dial
on
the
other
hand is
considerably
more
accu
rate
especially
at
the
low end.
The
welding
machines
current
should be within
1
per
cent
or
1
ampere
(whichever
is
great
er) of
the
dial
setting.
Thus
if the
digital
dial is
set to
10
amperes
the weld
current
output
will
be within
–
1
ampere.
It
becomes obvious that
the
digital
dials should
always
be trusted
as more
accurate
than
the
panel
ammeter.
A
simple
guide
to
following
is:
Up
to
100
amps,
accuracy
is
–
1
amp.
Above
100
amps,
accuracy
is
–
1
per
cent.
In
practice,
it is
found
that dial
accuracy
is
even
more accu
rate
than
the
specified
1
per
cent.
Production
tests
include
factory
calibration
using
1/2
per
cent
laboratory quality
instruments.
A.
Recorder Jacks
NOTE
The
current
signal
output
is 0
to
50
millivolts
dc
and
the
voltage signal output
is
0
to
85
volts dc.
Near
each
meter
is
a
set
of
red and
black
test
jacks.
These
can
be
used
to
supply
signals
representing
arc
current
and ter
minal
voltage
to remote
chart
recording
instruments.
Al
though
these
outputs
are
equipped
with
R.F.
chokes,
care
should be
taken
when
connecting
to
the
inputs
of
sensitive
instruments.
Note
that
the
negative
(black)
post
of
the
cur
rent
signal
is
electrically
common
with
the
positive
(red)
post
of
the
voltage
signal.
This
signal
should be
investigated
when
using
a
common
-
chassis
input
multi-channel
recorder.
Page
10

20% On
Time
Figure
4-4. Pulse ON1 Time
TA-901 410-2
C.
Pulse
Frequency
Control
(Figures
4-1
&
4-3)
The
number of
pulses
per
second is
determined
by
the
PULSE
FREQUENCY
Control
dial which is measured and
calibrated
in
pulses
per
second.
The
frequency
range
available
is
from
1
-
10.
(This
is the
number
of
pulses
injected
into the
weld
current
per
second.)
Due
to
the
fact
that
the
PULSE
FREQUENCY
Control
is
not
linear,
it
will
be
necessary
to
refer
to
Figure
4-5
whenever
it
is
necessary
to convert
the
dial
setting
to
pulses
per
second.
IMPORTANT
The
use
of
a
low
input
impedence
recorder
or
a
second
(remote)
ammeter
connected
to
the
ampere
recorder
jack
will
throw the
panel
ammeter out of calibration
while
in the
SET-UP Mode.
B.
Peak Current
Control
(Figures
4-1
&
4-3)
The
PEAK
CURRENT Control
on
the front
panel
allows
the
adjustment
of the
pulse
current
level
(amplitide).
This
con
trol
provides
the
operator with
a
means
of
injecting
enough
current
momentarily
into
the weld
puddle
to
cause
the
weld
puddle
to
grow
in
depth
and width.
The
PEAK
CURRENT
(pulse
amplitude)
Control
operates
independently
of
the
WELD/BACKGROUND
CURRENT
Control. To
adjust
the
peak
current
level,
the
panel
ammeter
can
be used
in
conjunction
with the
SET-UP
Mode
or
the
peak
current
level
can
be
adjusted
by
referring
to
Table 4-2
which translates
dial
readings
(0 to
1000) into
peak
current
(0
to
300)
amps.
Table 4-2.
Amperes
VS
0-1000 Dial
Calibration
(Pulse
Peak,
Initial And
Final
Current Dials)
4
-
9. OPERATION OF
PULSE CONTROLS
In
Gas
Tungsten-Arc
(Tig)
Welding. pulsing
refers
to
the
alternate
raising
and
lowering
of the
main
weld
current at
a
periodic
rate.
The
raised
portions
of the
weld
current
are
controlled
in
width,
height,
and
frequency
thus
forming
pulses
of
weld
current.
These
pulses
and the lower
current
level
between them
(called
the
background
current)
alter
nately
heat and cool the
molten
weld
puddle.
The
combined
effect
gives
the
operator
better
control of
penetration,
bead
width,
crowning, undercutting,
and
puddle slag
in
out
of
position
welding,
specifically
vertical
up,
The
pulsing
fea
ture
can
be utilized either
alone
or
in
conjunction
with
alec
troslope
if
the
welding
power
source
is
so
equipped.
A. Pulse Width
(Percent
ON
Time)
Control
(Figures
4-1
&
4-3)
The PULSE WIDTH Control
regulates
how
long
the
pulse
current
will be
on
during
one
pulse cycle.
The
control dial
is
calibrated from
0
to
1000. Table
4-1
shows
the
PULSE
WIDTH
Control dial
calibrations
and
percent
on
time
of
the
pulse
for
various
dial
settings.
Table 4-1. Pulse
Width Dial
Settings
VS Percent
On
Time
Dial
~
%
ON
Time
Setting
Of Peak
Current
0
10%
50 23%
100 35%
200
50%
300
60%
400
66%
500
72%
600 75%
700
80%
800
83%
900 86%
1000
90%
The
minimum
on
time
available
during
one
pulse cycle
is
10
percent
of
the
cycle.
The
maximum
on
time
of
the
pulse
cycle
is
approximately
90
percent.
Figure
4-4
gives
an
example
of
the
on
time
adjustment.
50%
On
Time
-r---n n
n
ff~
P
eo%On
Time
~LJLJ4i~~
For
Weld
Current
Amps
Set
Dial
To
For
Weld
Current
Amps
Set
Dial
To
For
Weld
Current
Amps
Set
Dial
To
3
010 34
113
80
267
4
013
35 117
82
274
5
017
36 120
84 280
6
020
37
123
86
287
7
023
38 127
88 294
8 027
39 130
90
300
9
030
40 133
92 307
10 033
41
137
94 314
11
037
42
140
96
320
12 040
43 142
98 326
13 043
44 147
100 333
14
047
45 150 105
350
15 050
46 153 110
366
16 053
47
157 115
383
17
057
48 160
120 400
18
060 49 163
125
427
19
063 50
167
130
433
20 066
52
173
135
450
21
070
54
180
140
466
22
073
56 187
145
483
23
077
58 193 150
500
24
080
60
200
160 534
25
083
62 207
170
566
26
087
64 214
180
600
27
090
66 220
190 633
28 093
68 227 200
667
29 097
70
234 220 733
30
100
72
240 240
800
31 103
74
247
260
866
32
107
76 254 280
933
33
111
78
260
300 1000
A selector
relay,
located
on
the
pulsar
circuit
board,
alter
nately
selects either
the
background
current
signal
or
the
peak
current
signal.
Thus,
if
the
PEAK
CURRENT
Control
is
set
higher
than
the
WELD/BACKGROUND
CURRENT Con
trol,
the
control
signal
will
increase
when
the
relay
contacts
selecting
the
PEAK
CURRENT
Control
settings
are
in
use.
This
results
in
a
boosting
or
pulsing
of
the
weld
current
to
the
amplitude
preset
on
the
PEAK
CURRENT
Control dial.
This
is
considered
standard
pulsed
GTAW
procedure.
If
the
pulse
peak
current
is
set
equal
to
the
WELD/BACKGROUND
CURRENT
Control,
no
current
pulses
will be
evident
in
the
output.
if the
PEAK CURRENT
Control
is
set
below
the
WELD/BACKGROUND
CURRENT Control
the
pulses
will
be downward
in
direction,
not
the usual
method
of
opera
tion,
OM-215
Page
11

5.
Place
the POWER
Switch
in the
ON
position
and
press
the
START
Button
or
foot switch. If
the
welding
power
source
is
equipped
with
Electroslope,
depress
the
Upslope
push
button
so
that
it
advances
into
the weld condition.
At
this
point
the
panel
ammeter will read the AVERAGE
of
background
current and
pulses.
6.
Adjust
the
PEAK
CURRENT
Control until
the
ammeter
reads
the
current selected
in
step
1.
7.
Set
the
PULSE
FREQUENCY
Control
to
600.
This
repre
sents
2
pulses
per
second,
a
good
starting
point
for
trial
and
error
programming.
8.
Place
the
Function
Switch
in the
WELD
position
and
make
a
trial
weld.
Further
adjustments
of the
pulse
con
trols
can
be made
while
welding.
9. This
procedure
will
not
of
course
be
optimum
in
all
cases
but
it
provides
a
good
starting
point
and
can
be
used
with
a
workpiece
of
any
thickness.
4-10.
OPERATION OF
ELECTROSLOPE
The
electroslope
feature
provides
a means
of
current control
during
the
start
and
finish of the
weld.
Controls for
adjusting
the
initial
current, upslope time,
down-
slope
time
(crater-out) and final
current
level
at
the
conclu
sion of the weld
are
located
on
the
front of the
control
panel.
Upslope
and
downslope
of
weld
current
can
be
triggered
by
the
push
button
switches
on
the
control
panel
or
remotely
by
connecting
a
remote
switching
station
to
the
Remote
Control
Terminal
Block
)2T).
See
heading
3-6
for
instructions
on
connecting
a
remote
slope
control
switch. Various
devices
such
as
mechanically
actuated
switches
mounted
on
moving
fixtures
or
jigs,
or
an
optional
remote
pendant
control
can
be
used for this
purpose.
A. Initial
Current Control
(Figures
4-2
&
4-3)
The
INITIAL
CURRENT
Control
is used
to set the
arc cur
rent
at
the
moment
of
arc
initiation. The
current
will
be held
at
this
value
(sometimes
called
a
pre-heat
current)
until the
welding
power
source
is
triggered
into
upsiope.
To
go
directly
into
upslope
following
arc
initiation,
a
jumper
should
be
connected
between
terminals 72
and
120
of
ter
minal
strip
2T. To
go
directly
into
weld
current
under these
conditions (no
upslope),
set
the
UPSLOPE
TIME
Control to
0.
NOTE
When
operating
with
the
initial
current (or
preheat)
portion
jumpered
out,
even
though
the
transfer
from
arc
start
to
weld
or
background
current
level
is instan
taneous,
the
INITIAL
CURRENT
Control
remains
active in
the
circuitry
for that
short
instant
of
time
following
arc
initiation.
Accordingly,
it is
recom
mended that the
INITIAL
CURRENT
Control
not
be
set at
0,
it
should
be
set
up
to
or near
the
weld
)or
background)
current
value
as an
aid
in
arc
starting.
This
tends
to
presaturate
the
magnetics
of the
welding
power
source
thus
making
arc
starting
easier.
B.
Upslope
&
Downslope
Time
Controls
(Figures
4-2
&
4-3)
Two 10
turn
dials
are
furnished for
controlling
the
upslope
and
downslope
portions
of
the
weld
cycle.
These
dials
are
calibrated
directly
in
seconds,
0
to
10,
with
minor
gradua
tions
at
tenths of
a
second and hundredths
of
a
second. Set
ting
the
upslope
dial for 3
seconds for
instance,
will result in
the
current
changing
linearly
from
the value
set
on
the
INITIAL
CURRENT
Control
to
the value
set
on
the
WELD/
BACKGROUND
CURRENT
Control
over
a
period
of
3
seconds.
The
same
is
true
of
the
downslope,
if
it
is
set
for
5 seconds
for
instance,
the
weld
current
will diminish
to
the
setting
of
the FINAL
CURRENT
Control
linearly
over
a
period
of 5
seconds.
These
slopes
can
be initiated
(triggered) by
the
push
buttons
on
the
front
panel
of
the
welding
power
source or
by
remote
push
buttons,
limit
switches,
etc.,
connected
to
the
2T
terminal
strip.
Upsiope
need
not
be
upwards
in
direction,
z
a
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-
~
- -
-
UR~!II
UENI~YDT
LSLTTIN
-
~Hfl~0U
C~
~
~--
1~-
IH–I:li~
- -
J--
~--
-~-~
T::
C~II–
FRROURNCY
DIAL SETTING
-
TURNS
EB-gOl
080-1
Figure
4-5. Pulse
Frequency
Versus
Dial
Setting
D.
Pulsing
Switch
(Figures
4-1
&
4-3)
This
switch
is
located
on
the
master
control
panel
and
allows
the
pulse
control
circuitry
to be turned
on or
off.
Placing
the
switch in
the
OFF
position
restores
the
welding
power
source
to
a
straight
line weld
current
output
with
the
WELD/BACKGROUND
CURRENT
Control
used
as a
main
weld
current
control.
Placing
the
switch
in
the
ON
position
energizes
the
pulse
control
circuitry
allowing
an
adjustable
pulse
control
signal
to
be fed
into the
welding
power
source
control
circuit
which
in
turn will
permit
controllable
pulsing
of the
main weld
current.
When
used with
electroslope,
even
though
the
PULSING
Switch
is in the
ON
position,
pulsing
will
not
begin
until the
welding
power
source
is
triggered
into
upsiope.
The
pulses
will
then
grow
in
magnitude
as
the
current
slopes
up.
Again,
at
the end of
the
weld
program,
pulsing
will
diminish
to
zero
at
the
end of
downslope.
The
initial
current
and
the
final
current
are
both
intentionally provided
without
pulses.
E.
Weld-Set
Up
Function
Switch
(Model
With Pulser
Controls
Only)(Figure
4-1)
This
switch allows the
pulses
to
be viewed
on
the
panel
ammeter
without
actually
drawing
an arc.
The
WELD
posi
tion
must
be
used
for
actual
welding.
The
SET-UP
position
allows
the
programming
or
pre-weld
set
up
of the
various
controls. No weld
power
is available
during
set-up.
When
in the
SET-UP
Mode,
and
using
a
remote (foot)
contac
tor
control,
it is
necessary
to
actuate
the
circuitry by depres
sing
the
foot
control
in
order
to
see
the
pulses
on
the
panel
ammeter.
-
F.
Setting
Up
Pulser
Controls
(Figures
4-1
&
4-3)
The
following
steps
are
intended
to
provide
an
approximate
starting point
when
performing
Pulsed Gas
Tungsten
-
Arc
Welding:
1.
Knowing
the
workpiece
thickness,
the
material,
and
the
tungsten
size,
establish the weld
current used
previously
if
welding
were
to
be
performed
without
pulsing.
2. Turn
the
welding
power
source
Function
Switch
to
SET
UP.
3. Turn the
PULSE FREQUENCY
Control full
clockwise
to
the
1000
(lOpps)
position
and
place
the PULSE WIDTH
Control
to
the
200
position
on
the dial
(50
per
cent
on
time,
50
per
cent
off
time).
With
these
two
dials
posi
tioned
as
such,
the
panel
ammeter
(with
its slow
response)
will
read
the
combined
average
of
background
current
and
pulses.
4. Set
the
WELD/BACKGROUND
CURRENT Control for
75
per
cent
of the
current
value which
was
selected
in
step
1. For
example:
If
100
amperes
was
selected,
set
the
WELD/BACKGROUND
CURRENT
Control for 75
amperes.
Page
12

it
can
be
adjusted
for
a
drop
off
in
current
if
desired
by
setting
the
INITIAL
CURRENT
Control
to a
higher
level
than
the
WELD/BACKGROUND
CURRENT
Control.
Con
versely,
downslope
need
not
be downward
in
direction
but
can
be
set
for
an
increase of
current
at
the
end
of the
weld.
Since
both the
upslope
and
downslope
dials
are
calibrated
in
time,
the
current
change during
sloping
can
be
from
any
value within the
range
of
the
welding
power
source
to
any
other
value
and
no
interaction
with the
time
control
will
occur.
C. Final
Current
Control
(Figures
4-2
&
4-3)
The
final
current
level
is
controlled
by
the
FINAL
CUR
RENT
Control. The
FINAL
CURRENT
Control
has
an
adjustable
range
from
the
minimum
to
the
maximum
output
of
the
welding
power
source.
Whatever
final
current
level
is
selected
will
be held
until the
program
is
stopped by
opening
the
contactor,
if
in
the
GTAW
MANUAL
mode. In the
GTAW AUTO
mode,
the
emergency
stop
button
provision
at
2T
must be used,
If
this
control
is
set at
a
level
higher
than
the
WELD/
BACKGROUND
CURRENT
level,
an
upward slope
will take
place
when the
downslope
portion
of
the
weld
is initiated.
However,
in
most
applications,
the
final
current
level
is
generally
set
at
a
level
lower, than the
WELD/BACK
GROUND
CURRENT
level
in
order
to
provide
a
cratering
out
end
to
the weld.
D. Function
Switch
(Figures
4-2
&
4-3)
1.
Set-Up
The
SET-UP
mode
is
particularly
useful
in
pre-scheduling
initial and final
slopes
and
in
setting
the
current
level
desired
for
the
initial
current
and final
current.
Turn
the
Function
Switch
to
SET-UP
and the initial
current
can
be read
directly
and
adjusted
by
reading
the
panel
meter.
Depressing
the
up
slope push
button
will
then
display
the
upslope
time
and the
weld
or
background
current
value
(which
should
agree
with
the
setting
of
the
digital
current
dial).
Next,
the
downslope
push
button
can
be
depressed
which will then
display
the
downslope
time
and hold
at
the final
Current
value.
This
can
then be
adjusted
by
means
of
the final
current
dial,
To
reset
from the
SET-UP
mode
it
is
necessary
to
momentarily place
the
POWER Switch
in the
OFF
position.
2. GTAW Manual
The GTAW
MANUAL
mode
must
be used
when
hand
or
manual torch
operation
is
being
employed.
The
contactor
control
switch
must
be
held closed
to
weld
in
this mode of
operation.
When
welding
in
theGTAW
MANUAL
mode
(i.e.,
with foot
control),
it is
recommended
that
a
jumper
be installed be
tween terminals
72
and
120
on
terminal
strip
2T.
This will
take
the
operator
directly through upslope
to
the
direct
read
ing
WELD/BACKGROUND
CURRENT Control
as soon
as
the
arc
is initiated.
Set
the
upslope
time
to
zero.
To
obtain
better
starts
when this
operation
is
performed,
the
INITIAL
CURRENT Control
should
be
set
somewhat above
zero.
If
a
jumper
is
not
installed,
the
current
will
be
held
at
the
setting
of
the
INITIAL CURRENT
Control and
the
foot control
becomes
a
vernier
of
it.
The
operator
will have
a
choice
at
the
end
of
the manual weld
to
either
Crater-out
with
a
foot
con-
trol
or
by closing
a
momentary
contact
switch
(connected
between
terminals
120 & 107
on
terminal
strip
2T)
use
the
downslope
portion
of
the
electroslope.
3. GTAW
Auto
The
GTAW AUTO
mode
places
the
welding
power
source
in
an
automatic
mode of
operation
controlled
by
the
contactor
control, upslope. downslope,
and
stop
switches.
In
order
to
start
the
weld
program
sequence
(go
into
initial
current)
the
contactor
control switch
must
be
momentarily
depressed.
The
contactor
control switch
may
be
either
con
nected
to
the
Remote
Start
(contactor)
Receptacle
or
to
ter
minals 160 and 113
on
terminal
strip
2T,
both
of which
are
located behind the lower front
access
door
(See
Figure
3-4).
By momentarily depressing
the
Upslope
Start Button
on
the
front
panel
or
the Remote
Upslope
Switch
(See
heading
3-6
for
Remote
Upslope
Switch
Connections),
the
welding
power
source
will
go
from
the
initial
Current
setting
into
upslope.
Once
upslope
is
completed
the
welding
power
source
will
automatically
level
off
at
the WELD/BACKGROUND
CUR
RENT
Control
setting,
In
order
to
go
from
the
WELD/
BACKGROUND CURRENT
Control
setting
into
downslope,
the Downslope Start Button
on
the
front
panel
or
Remote
Downslope
Switch
(See
heading
3-6
for Remote
Downslope
Switch
connections)
must
be
momentarily depressed.
This
will
take
the
operator through
downslope
and
automatically
level off
at
the final
current
level. The
welding
power
source
will
remain
at
the final
current
level until the
Remote
Momentary Stop
Switch
is
depressed
(See
heading
3-4A
for
connections).
4-11, VOLT-AMPERE
CURVES
(Figure
4-6)
90
80
70
60
0
>
50
40
30
20
10
The
volt-ampere
curves
show the
output voltage
available
at
any
given
output
Current
within the
limits of the
minimum
and
maximum
of
the
weld
current
control. A
curve
has
been
plotted
for
every
50
amperes
of
welding
current to
aid
in
selection of
proper
operating voltage.
Due
to
the fact
that this
welding
power
source
is
of
the
constant current
type
it will
be
noted
on
the
volt-ampere
curve
that
a
considerable
amount
of
voltage change
is
permit
ted
without variation
in
the
current.
03
MIN.
Figure
4-6.
Volt-Ampere
Curves
SECTION 5
-
SEQUENCE
OF
OPERATION
!
Never,
under
any
circumstances,
operate
the
welding
power
source
with
any
portion
of
the
outer
enclosure
removed.
In addition
to
a
safety
hazard,
improper
cooling
may
result
in
damage
to
the
welding
trans
former and
the
welding
power
source
components.
Warranty
is
void if the
welding
power
source
is
opera
ted
with
any
portion
of
the
outer
enclosure
removed.
5-1.
GAS TUNGSTEN-ARC WELDING GENERAL
NOTES
When
performing
manual
GTAW
welding
with
a
remote
foot
amperage
and
contactor
control,
remember
that
if
the foot
control is advanced
only
a
slight
amount (cracked)
the
weld
current
will
be at absolute
minimum,
three
amps
or
less,
This
makes
arc
starting
considerably
difficult.
Accordingly,
it is
recommended that the
STARTING
CURRENT SELECTOR
Switch
be
set
to
the
No. 2
position
whenever
a
remote
foot
control
is
in
use
with helium
or
argon.
50
100 150
200 250 300
350
D.C.
AMPERES
EA-901
410-1
I
I
OM-215
Page
13

As
a
further
help
in
manual
GTAW
welding,
it is
always
best
to
have
the
electrode
holder
in
position;
ready
to
strike
the
arc
before
the
foot
pedal
is
depressed.
This
will
ensure
that
the
first starting
pulse
will
not
be
wasted.
If
the
foot
pedal
is
depressed
while the
electrode
holder
is
still
a
considerable
distance from the
workpiece,
the
high-frequency
will
strike
too
soon
and the
initial
starting
pulse
will
be wasted
trying
to
establish
an
impractically long
arc.
The
relays
will
then
reset,
chatter,
etc.
This
is normal
operation
and
should
be
expected
if the
high-frequency
is
energized
before
the
electrode holder
is in
welding
position.
To
summarize:
For best
starts, always
have
the
electrode
tip
within
1/8
inch
of
the
workpiece
before
depressing
the
foot
control.
5-2.
MANUAL
GAS
TUNGSTEN-ARC WELDING
(Figure
5.1)
1.
Make
all
connections
required
as
instructed in Section
2 of this
manual.
2. Rotate
the
WELD/BACKGROUND
CURRENT
Con
trol (or
INITIAL CURRENT
Control
on
models
with
electroslope)
to the desired
setting.
3.
If
a
Remote
Current
Control
is
not to
be
used, place
the
CURRENT CONTROL
Switch
in
the STANDARD
position.
If
a
Remote
Current
Control
is
to
be
used,
place
the
CURRENT
CONTROL Switch
in the
RE
MOTE
position.
4.
Place
the
STARTING CURRENT SELECTOR Switch
in
the
desired
position.
5.
Place
the
HIGH-FREQUENCY Switch
in
the
desired
position.
6.
Set
all
pulser
controls
to
the
desired
setting.
(Models
with
pulse
control
only).
7.
Set
the
POST-FLOW
Timer for
the
desired
amountof
post-flow
time.
8.
Place
the
Function Switch
in
the
WELD
or
GTAW
manual
position.
9.
Place
the
POWER
Switch
in
the
ON
position.
The
pilot
light
should
now
be
illuminated.
I
Prior
to
welding,
it is
imperative
that
proper
protective
clothing
(welding
coat
and
gloves)
and
eye
protection
(glasses
and/or
welding
helmet) be
put
on.
Failure
to
comply
may
result in
serious
or
permanent
bodily
L
damage.
. 
10. Turn
on
the
shielding
gas
and coolant at
the
respective
sources.
11.
Close
the Remote
Contactor Control
Switch
and
com
mence
welding.
12. The
WELD/BACKGROUND
CURRENT
Control
(or
INITIAL
CURRENT
Control
on
models
with
electro
slope)
may
be
adjusted
while
welding.
5- 3.
AUTOMATIC
GAS
TUNGSTEN-ARC
WELDING
(Models
With
Electroslope
Only)
1.
Make
all
connections
required
as
instructed in
Section
2 of
this
manual.
2. Rotate
the
INITIAL
CURRENT
Control
to
the de
sired
setting.

I
3.
Rotate
the
WELD/BACKGROUND
CURRENT
Con
trol
to
the
desired
setting.
4.
Rotate
the
FINAL
CURRENT
Control to
the
desired
setting.
5.
Rotate
the
(JPSLOPE
TIME
Control to
the
desired
setting.
6.
Rotate
the
DOWNSLOPE
TIME
Control
to
the desired
setting.
7.
Set
all
pulse
controls
to
the desired
setting
if
the weld
ing
power
source
is
so
equipped
and
it is
desired
to
use
the
pulse capability.
8.
Place
the
Function
Switch
in the
GTAW
AUTO
posi
tion.
9.
If
a
Remote
Current
Control
is
not to
be
used, place
the
CURRENT
CONTROL
Switch
in the
STANDARD
position.
If
a
Remote Current
Control
is
to be
used,
place
the CURRENT
CONTROL
Switch
in the
RE
MOTE
position.
10.
Place
the
STARTING
CURRENT
SELECTOR
Switch
in the
desired
position.
11.
Place
the
HIGH-FREQUENCY Switch
in
the desired
position.
12.
Set
the
POST-FLOW
Timer
for
the
desired
amount
of
post-flow
time.
13.
Place
the
POWER Switch
in the
ON
position.
!t~hhhh1.1~1_1J
Prior
to
welding,
it is
imperative
that
proper
protective
clothing
(welding
coat
and
gloves)
and
eye
protection
(glasses
and/or
welding
helmet) be
put
on.
Failure
to
comply
may
result
in serious
and
even
permanent
bodily
damage.
14.
Momentarily
close
the Remote
Contactor
Control
switch
to
go
into
the
initial
Current
portion
of the
weld.
15.
Momentarily
close
the
upslope
switch
to
go
into
up-
slope
and weld
current.
16.
Momentarily
close
the
downslope
switch
to
go
into
downslope
and final current.
17.
Momentarily
depress
the
Remote
Stop
Switch
to
stop
the weld.
SHUTTING
DOWN
1.
Break
the
arc.
2. Allow
the
welding
power
source
to
idle
for 3
minutes
with
no
load
applied.
3.
Place the
POWER
Switch
in the
OFF
position.
4.
Turn
off the
shielding
gas
if
used.
1E4~Uil.]~IlIlI]
If
welding
is
performed
in
a
confined
area,
failure
to
turn
off the
shielding
gas
supply
could
result
in
a
build
up
of
gas
fumes,
thereby
endangering
personnel
re
entering
the
welding
area.
5-4.
Page
14

SECTION
6-
MAINTENANCE
1uu~unr.]nhuiIJ
Be
sure
the branch circuit
or
main disconnect switch
is
open
or
the electrical
input
circuit
fuses
are
removed
before
attempting
any
inspection
or
work
on
the
inside
of
the
welding
power
source.
Placing
the
POWER
Switch
on
the
welding
power
source
in the
OFF
position
does
not
remove
voltage
from the
power
terminals inside of the unit.
6-1. FAN MOTOR
All
models
are
equipped
with
an
exhaust
fan and
rely
on
forced
draft for
adequate
cooling.
The fan
motor
is
manu
factured with
lifetime-lubricated
sealed ball
bearings
and
no
attention should be
required.
6-2.
TRANSFORMER
Occasional
blowing
out
of the dust and dirt from around
the
transformer
is
recommended.
This
should be done
period
ically depending
upon
the location
of
the
unit
and
the
amount
of
dust
and dirt
in
the
atmosphere.
The
welding
power
source
outer
enclosure
should
be
removed and
a
clean
dry
air
stream
should be used
for
this
cleaning
operation.
6-3. RECTIFIER
It is
recommended that the
rectifier
be cleaned
occasionally
by
blowing
it
out
with compressed
air.
This
cleaning
opera
tion
is
necessary
so
that
maximum
cooling
will
be
accom
plished
by
the air
stream.
This
should
be done
periodically,
depending
upon
the
location
of the
unit
and
the
amount
of
dust and dirt in the
atmosphere.
It
is
necessary
to
remove
the
outer
enclosure
for
this
cleaning operation.
6- 4. SPARK
GAP
(Figure
6-1)
The
spark
gaps
can
be
readily inspected by
opening
the
access
door
on
the front of the
welding
power
source.
The
spark
gaps
are
normally
set at
.008
clearance
at
the
factory.
It
will
be
necessary
to
periodically
readjust
these
after extended
operation.
Usually
inspection
and
adjustment
every
three
or
four months
will
suffice.
Readjustment
is also
indicated when intermittent
operation
of
the
gaps
is noted.
Usually
this
occurs
when the
setting
has
increased
to
.013
or
greater.
Generally
speaking,
the
high-frequency output
varies
directly
(up
to
a
certain
point)
with
the
spark
gap
spacing.
In
extreme
cases
where
the
greatest
amount
of
high-frequency
is
needed,
it
may
be
necessary
to
adjust
the
spark
gap
setting
to
.010
or even
.013.
This also
increases
the
high-frequency
radia
tion and it is
suggested
that
the
minimum
gap
setting
(.004
to
.008),
consistent
with
good
welding
operation,
be
used.
NOTE
Cleaning
or
dressing
the
points
of
the
spark
gaps
is
not
recommended,
as
the
material
at
the
points
is
tungsten
and
is
impossible
to
file.
The
entire
point
should
be
replaced
when the
tungsten
section
has
completely
disappeared.
To
Adjust
the
Spark
Gaps,
Proceed
as
Follows:
1.
Loosen
screw
A
on
both
sides.
2. Place
feeler
gauge
of
proper
thickness
between
points
at
gap
C.
3.
Apply
slight
pressure
against
point
B
so
feeler
gauge
is
held
firmly
in
gap.
4.
Tighten
screws
A.
Figure
6-1.
Spark
Gap
Adjustment
6-5.
CIRCUIT
PROTECTION
Fl

6
amp,
cartridge
fuse
protects primary
side
of
control
transformer. Located
in
back of
the
center
air
baffle
inside of
the
welding
power
source.
CB1

3
amp.
circuit
breaker,
protects
115
vac
control
cir
cu
it.
CB2
10
amp.
circuit
breaker,
protects
115
vac
duplex
receptacle
circuits.
CB3 3
amp.
circuit
breaker,
protects
30
volts control cir
cuit.
CB4
5
amp.
circuit
breaker,
protects
mag-amp
115
vac con
trol
circuit.
rr1
All
circuit
breakers
are
located behind
the
lower front
access
door.
6-6.
THEORY
OF OPERATION: CLOSED LOOP
FEED
BACK
SYSTEM
I
~
1
For
easy
access
to
printed-circuit
boards,
remove
the
four
screws
at
the
corners
of the front
nameplate.
This
welding
power
source
utilizes
three
or
four
(depending
on
model
type)
printed
circuit boards
in
its
standard
control
circuitry.
One
board
serves
as
the
regulated
power
supply
furnishing
proper
voltages
to
the control
amplifier
on
the
second
board.
A.
Power
Supply
Board
This
board
receives
two ac
voltages
from transformer
T50,
rectifies
each
(rectified
by
diodes
D50
thru
D47),
where
upon
the
resulting
two
dc
voltages
are
fed
to
series
regulators,
050,052,
and
054. Zener
diode
D58
serves as a
reference
for
the
positive
15
amp
10 volts
regulators.
The resistor
divider,
R57,
R58,
and
R59
senses
the
positive
15
volts
dc
output,
053 makes
a
comparison
between
the
output
and
reference
voltage,
amplifies
the
error
if
any,
and
regulates
the series
drop
of
052
to
hold the
output
constant.
Q51
does
the
same
for
the
10
volts
regulator
and
drive
050.
The
negative
15
volts
regulator operates
in the
same
manner
as
the
positive
15
volts
regulators,
but
with
054
serving
as
the series
regulator.
The
positive
24
volts
dc
output
is
not
regulated
and
is
used
to
supply
the
relay
coil
current
of
CR50.
It
may
measure
any
where
from 24
to
33
volts
with the
latter
being
no
(relay)
load
condition.
I
.
1
.
TA-020
623-42
I
U
U
U
I
I
OM-215
Page
15

connect resistor
R82
across
integrator
network
C62
and
R83
thus
preventing
a
charge
buildup
on
C62.
A
charge
buildup
on C62
could
cause a
hot-start
condition.
The
contacts
of
relay
CR50
also
place
resistor
R75
into
the
circuit
which
adjusts
the
amount
of
pre-saturation
in
mag
netic
amplifiers
1
through
6. When
arc
initiation
occurs,
relays
CR50
and CR52
are
deenergized.
This
deenergiza
tion
action
removes
resistor
R82
from
the
circuitry
and
thus allows
normal
integrator
action.
Also
at
this
time,
resistor R75 will
be
removed
from the
circuit
while the
normal drive
signal
from
A51
is switched
to
the
output
exit
and in
turn
out to
the
booster
stage
(01
& 02).
The
contacts
of
relay
CR52
connect
the
drive
signal
to the
welding
power
source
ammeter
if
in
the
SET-UP
mode.
4.
R88
adjusts
the
drive
signal
to
the
current
booster
and
determines overall
system
gain.
Do
not
readjust
this
trim
mer.
5.
RFC5O
and 51
are
transient
suppressors.
6.
C61
is
a
transient
voltage
bleeder
for
the
transductor feed
back
signal.
7.
R80
is
an
offset
adjustment
potentiometer
used to cali
brate the
welding
power
source
output
at the
low
end
(5
ampere
point).
C.
Current
Booster
The
transistorized
current booster accepts
the
0
to
positive
10
volts dc
signal
from
the
pre-amplifier,
through
R88
and
boosts
it
from
approximately
.015
amperes
to
.8
amperes.
NOTE
Resistors
R6
and R7
are
Fusistors
designed
to
burn
open
in
event
of
overload.
These
are
located
under
the
transistor heat sink
and
are
soldered
in
place.
There
is
inherent
redundance built
into
the
current
booster,
if
one
transistor
should
fail,
the other
will
satisfactorily
take
over
the
load.
I
I
D.
Start Control
Circuit
To
permit
better
starting,
two
delays
have
been
designed
into
the
welding
power
source.
The
first
begins
at
contactor ener
gization.
TD2
delays
the
application
of
high-frequency
for
1/4
of
a
second,
giving
the
magnetics
time
to
stabilize.
The
second
delay
begins
at
the
moment
the
arc
starts
and
lasts
for
approximately
160
milliseconds
thereafter. This
delay
times
a
separate
starting
current
source
which
is
applied
to
the electrode
by
W2. The
starting
current
source
is
sepa
rate
from
the
main
welding
current
source:
Rectifier SRS
provides
the
dc,
resistors
R18
and
A19
and
Switch 553B
set
the
current.
Capacitor
Cl 2
and
the
coil of
relay
CR3
determine the
length
of
the
starting
current
pulse
(l6omsec).
This
time-out
begins
at
the
instant
of
arc
initiation
as
sensed
by
CR1.
6-1.
INTEGRATOR-PRE-AMP
BOARD
CALIBRATION
1.
Adjust
Weld
control
to
300
amps.
2. Turn
High-Frequency
starter
to
off.
3.
Turn
Upslope
Rate
to
0
if the
welding
power
source
has the
electroslope
feature.
4.
Set
the
GTAW-Auto
-
GTAW
Manual
-
Set
Up
switch
to
GTAW
Auto
or
Weld
in
certain
models.
5.
Turn
Pulser
off
if
welding
power
source
has this
feature.
6-
Use
appropriate
torch
suitable for
300
amps
or
dummy
load
welding
power
source
to obtain
approxi
mately
15 load
volts
(not
less than
9
volts)
@300
load
amps.
A
length
of
small
weld cable
approximately
75
feet
long
can
be
used.
7.
The
board
contains 6 Calibration
trimmers.
NOTE
I
I
The
four
voltage
outputs
are
all
common
to
ground.
The
term
Ground,
as
used
here,
is
not
chassis
or
frame
potential,
but
is
intended
to
mean
a
common
bus
or
datum
line.
-I
I
-J
I
1.
Electroslope
Board
2. Pulser
Board
3.
Integrator
Board
4. Power
Supply
Board
I
TC-901
417-5
Figure
6-2.
Printed
Circuit
Board
Location
B.
Integrator
Board
The
second
printed
circuit
board
serves
as an
integrator
and
pre-amplifier.
Two
operational
amplifiers,
ASS
and
A51
are
mounted
on
this
board
along
with
associated
circuitry.
These
are
very
high
gain
amplifiers
with
controlled
feedback.
While
welding,
Amplifier
A55
receives
two
inputs,
one
from
the
0
to
positive
10
volts
reference
through
R73
and
the other
from
the transductor
feedback
rectifier
SR3
(0 to
negative
10
volts)
through
R81.
Amplifier ASS,
connected
as
an
aug
menting
integrator, produces
an
output
with
a
component
proportional
to
its
dc-input
plus
a
component
proportional
to the time
integral
of
its
input.
The
integrating
RC
is
made
up
of
R83
and
C62.
This
input signal
is fed
through
R85
to
the
input
of
pre
amplifier
A51.
Here it
is
inverted from
a
negative-going
signal
to
a
positive-going signal.
The
gain
of
this
stage
is
adjusted
by
R87.
The
functions of other
components
on
the
board
are
as
fol
lows:
1.
R78
calibrates the
welding
power
source
by
adjusting
the
feedback
so
that
the
actual
weld
current
out
agrees
with
the
current
setting
indicated
on
the
digital
dial of
the
multi-turn
weld
control.
2.
R73
is
an
input
resistor
to A55. D71
and
072
are
isola
tion diodes
used
to
isolate
the
0
to
10
volts
reference
signal
and the
welding
power
source
minimum
output
level
signal.
3.
Relays
CR50
and
CR52 switch
from
a
start
condition
to
a
weld
condition. These
relays
are
energized
prior
to
arc
initiation
by
the
24
volts
dc
supply
through
the
contacts
of
relays
CR58
and
CR66.
The
contacts
from
relay
CR50
Page
16