Lincoln Electric PRECISION TIG IM936 User manual

PRECISION TIG 375
OPERATOR’S MANUAL
IM936
April, 2007
Safety Depends on You
Lincoln arc welding and cutting
equipment is designed and built
with safety in mind. However, your
overall safety can be increased by
proper installation ... and thoughtful
operation on your part. DO NOT
INSTALL, OPERATE OR REPAIR
THIS EQUIPMENT WITHOUT
READING THIS MANUAL AND
THE SA ETY PRECAUTIONS
CONTAINED THROUGHOUT.
And, most importantly, think before
you act and be careful.
For use with machines having Code Numbers: 11163
• Sales and Service through Subsidiaries and istributors Worldwide •
Cleveland, Ohio 44117-1199 U.S.A. TEL: [phone] FAX: [phone] WEB SITE: www.lincolnelectric.com
• World's Leader in Welding and Cutting Products •
Copyright © Lincoln Global Inc.
IP21S
N80
IEC 60974-1

OR ENGINE
powered equipment.
1.a. Turn the engine off before troubleshooting and maintenance
work unless the maintenance work requires it to be running.
____________________________________________________
1.b.Operate engines in open, well-ventilated
areas or vent the engine exhaust fumes
outdoors.
____________________________________________________
1.c. o not add the fuel near an open flame weld-
ing arc or when the engine is running. Stop
the engine and allow it to cool before refuel-
ing to prevent spilled fuel from vaporizing on
contact with hot engine parts and igniting. o
not spill fuel when filling tank. If fuel is spilled,
wipe it up and do not start engine until fumes
have been eliminated.
____________________________________________________
1.d. Keep all equipment safety guards, covers and devices in posi-
tion and in good repair.Keep hands, hair, clothing and tools
away from V-belts, gears, fans and all other moving parts
when starting, operating or repairing equipment.
____________________________________________________
1.e. In some cases it may be necessary to remove safety
guards to perform required maintenance. Remove
guards only when necessary and replace them when the
maintenance requiring their removal is complete.
Always use the greatest care when working near moving
parts.
___________________________________________________
1.f. o not put your hands near the engine fan.
o not attempt to override the governor or
idler by pushing on the throttle control rods
while the engine is running.
___________________________________________________
1.g. To prevent accidentally starting gasoline engines while
turning the engine or welding generator during maintenance
work, disconnect the spark plug wires, distributor cap or
magneto wire as appropriate.
i
SA ETY
i
ARC WELDING CAN BE HAZARDOUS. PROTECT YOURSEL AND OTHERS ROM POSSIBLE SERIOUS INJURY OR DEATH.
KEEP CHILDREN AWAY. PACEMAKER WEARERS SHOULD CONSULT WITH THEIR DOCTOR BE ORE OPERATING.
Read and understand the following safety highlights. For additional safety information, it is strongly recommended that you
purchase a copy of “Safety in Welding & Cutting - ANSI Standard Z49.1” from the American Welding Society, P.O. Box 351040,
Miami, Florida 33135 or CSA Standard W117.2-1974. A Free copy of “Arc Welding Safety” booklet E205 is available from the
Lincoln Electric Company, 22801 St. Clair Avenue, Cleveland, Ohio 44117-1199.
BE SURE THAT ALL INSTALLATION, OPERATION, MAINTENANCE AND REPAIR PROCEDURES ARE
PER ORMED ONLY BY QUALI IED INDIVIDUALS.
WARNING
Mar ‘95
ELECTRIC AND
MAGNETIC IELDS
may be dangerous
2.a. Electric current flowing through any conductor causes
localized Electric and Magnetic Fields (EMF). Welding
current creates EMF fields around welding cables and
welding machines
2.b. EMF fields may interfere with some pacemakers, and
welders having a pacemaker should consult their physician
before welding.
2.c. Exposure to EMF fields in welding may have other health
effects which are now not known.
2.d. All welders should use the following procedures in order to
minimize exposure to EMF fields from the welding circuit:
2.d.1. Route the electrode and work cables together - Secure
them with tape when possible.
2.d.2. Never coil the electrode lead around your body.
2.d.3. o not place your body between the electrode and
work cables. If the electrode cable is on your right
side, the work cable should also be on your right side.
2.d.4. Connect the work cable to the workpiece as close as
possible to the area being welded.
2.d.5. o not work next to welding power source.
1.h. To avoid scalding, do not remove the
radiator pressure cap when the engine is
hot.
For iesel Engines: iesel engine exhaust and
some of its constituents are known to the State
of California to cause cancer, birth defects, and
other reproductive harm.
For Gasoline Engines: The engine exhaust from
this product contains chemicals known to the
State of California to cause cancer, birth defects,
or other reproductive harm.
CALI ORNIA PROPOSITION 65 WARNINGS

ii
SA ETY
ii
ARC RAYS can burn.
4.a. Use a shield with the proper filter and cover
plates to protect your eyes from sparks and
the rays of the arc when welding or observing
open arc welding. Headshield and filter lens
should conform to ANSI Z87. I standards.
4.b. Use suitable clothing made from durable flame-resistant
material to protect your skin and that of your helpers from
the arc rays.
4.c. Protect other nearby personnel with suitable, non-flammable
screening and/or warn them not to watch the arc nor expose
themselves to the arc rays or to hot spatter or metal.
ELECTRIC SHOCK can kill.
3.a. The electrode and work (or ground) circuits
are electrically “hot” when the welder is on.
o not touch these “hot” parts with your bare
skin or wet clothing. Wear dry, hole-free
gloves to insulate hands.
3.b. Insulate yourself from work and ground using dry insulation.
Make certain the insulation is large enough to cover your full
area of physical contact with work and ground.
In addition to the normal safety precautions, if welding
must be performed under electrically hazardous
conditions (in damp locations or while wearing wet
clothing; on metal structures such as floors, gratings or
scaffolds; when in cramped positions such as sitting,
kneeling or lying, if there is a high risk of unavoidable or
accidental contact with the workpiece or ground) use
the following equipment:
• Semiautomatic DC Constant Voltage (Wire) Welder.
• DC Manual (Stick) Welder.
• AC Welder with Reduced Voltage Control.
3.c. In semiautomatic or automatic wire welding, the electrode,
electrode reel, welding head, nozzle or semiautomatic
welding gun are also electrically “hot”.
3.d. Always be sure the work cable makes a good electrical
connection with the metal being welded. The connection
should be as close as possible to the area being welded.
3.e. Ground the work or metal to be welded to a good electrical
(earth) ground.
3.f.
Maintain the electrode holder, work clamp, welding cable and
welding machine in good, safe operating condition. Replace
damaged insulation.
3.g. Never dip the electrode in water for cooling.
3.h. Never simultaneously touch electrically “hot” parts of
electrode holders connected to two welders because voltage
between the two can be the total of the open circuit voltage
of both welders.
3.i. When working above floor level, use a safety belt to protect
yourself from a fall should you get a shock.
3.j. Also see Items 6.c. and 8.
UMES AND GASES
can be dangerous.
5.a. Welding may produce fumes and gases
hazardous to health. Avoid breathing these
fumes and gases. When welding, keep
your head out of the fume. Use enough
ventilation and/or exhaust at the arc to keep
fumes and gases away from the breathing zone. When
welding with electrodes which require special
ventilation such as stainless or hard facing (see
instructions on container or MSDS) or on lead or
cadmium plated steel and other metals or coatings
which produce highly toxic fumes, keep exposure as
low as possible and below Threshold Limit Values (TLV)
using local exhaust or mechanical ventilation. In
confined spaces or in some circumstances, outdoors, a
respirator may be required. Additional precautions are
also required when welding on galvanized steel.
5. b. The operation of welding fume control equipment is affected
by various factors including proper use and positioning of the
equipment, maintenance of the equipment and the specific
welding procedure and application involved. Worker expo-
sure level should be checked upon installation and periodi-
cally thereafter to be certain it is within applicable OSHA PEL
and ACGIH TLV limits.
5.c.
o not weld in locations near chlorinated hydrocarbon vapors
coming from degreasing, cleaning or spraying operations.
The heat and rays of the arc can react with solvent vapors to
form phosgene, a highly toxic gas, and other irritating prod-
ucts.
5.d. Shielding gases used for arc welding can displace air and
cause injury or death. Always use enough ventilation,
especially in confined areas, to insure breathing air is safe.
5.e. Read and understand the manufacturer’s instructions for this
equipment and the consumables to be used, including the
material safety data sheet (MS S) and follow your
employer’s safety practices. MS S forms are available from
your welding distributor or from the manufacturer.
5.f. Also see item 1.b.
AUG 06

OR ELECTRICALLY
powered equipment.
8.a. Turn off input power using the disconnect
switch at the fuse box before working on
the equipment.
8.b. Install equipment in accordance with the U.S. National
Electrical Code, all local codes and the manufacturer’s
recommendations.
8.c. Ground the equipment in accordance with the U.S. National
Electrical Code and the manufacturer’s recommendations.
CYLINDER may explode
if damaged.
7.a. Use only compressed gas cylinders
containing the correct shielding gas for the
process used and properly operating
regulators designed for the gas and
pressure used. All hoses, fittings, etc. should be suitable for
the application and maintained in good condition.
7.b. Always keep cylinders in an upright position securely
chained to an undercarriage or fixed support.
7.c. Cylinders should be located:
• Away from areas where they may be struck or subjected to
physical damage.
• A safe distance from arc welding or cutting operations and
any other source of heat, sparks, or flame.
7.d. Never allow the electrode, electrode holder or any other
electrically “hot” parts to touch a cylinder.
7.e. Keep your head and face away from the cylinder valve outlet
when opening the cylinder valve.
7.f. Valve protection caps should always be in place and hand
tight except when the cylinder is in use or connected for
use.
7.g. Read and follow the instructions on compressed gas
cylinders, associated equipment, and CGA publication P-l,
“Precautions for Safe Handling of Compressed Gases in
Cylinders,” available from the Compressed Gas Association
1235 Jefferson avis Highway, Arlington, VA 22202.
iii
SA ETY
iii
Jan, 07
WELDING and CUTTING
SPARKS can
cause fire or explosion.
6.a. Remove fire hazards from the welding area.
If this is not possible, cover them to prevent
the welding sparks from starting a fire.
Remember that welding sparks and hot
materials from welding can easily go through small cracks
and openings to adjacent areas. Avoid welding near
hydraulic lines. Have a fire extinguisher readily available.
6.b. Where compressed gases are to be used at the job site,
special precautions should be used to prevent hazardous
situations. Refer to “Safety in Welding and Cutting” (ANSI
Standard Z49.1) and the operating information for the
equipment being used.
6.c. When not welding, make certain no part of the electrode
circuit is touching the work or ground. Accidental contact can
cause overheating and create a fire hazard.
6.d. o not heat, cut or weld tanks, drums or containers until the
proper steps have been taken to insure that such procedures
will not cause flammable or toxic vapors from substances
inside. They can cause an explosion even though they have
been “cleaned”. For information, purchase “Recommended
Safe Practices for the Preparation for Welding and Cutting of
Containers and Piping That Have Held Hazardous
Substances”, AWS F4.1 from the American Welding Society
(see address above).
6.e. Vent hollow castings or containers before heating, cutting or
welding. They may explode.
6.f.
Sparks and spatter are thrown from the welding arc. Wear oil
free protective garments such as leather gloves, heavy shirt,
cuffless trousers, high shoes and a cap over your hair. Wear
ear plugs when welding out of position or in confined places.
Always wear safety glasses with side shields when in a
welding area.
6.g. Connect the work cable to the work as close to the welding
area as practical. Work cables connected to the building
framework or other locations away from the welding area
increase the possibility of the welding current passing
through lifting chains, crane cables or other alternate circuits.
This can create fire hazards or overheat lifting chains or
cables until they fail.
6.h. Also see item 1.c.
6.I. Read and follow NFPA 51B “ Standard for Fire Prevention
uring Welding, Cutting and Other Hot Work”, available from
NFPA,1 Batterymarch Park,PO box 9101, Quincy, Ma
022690-9101.
6.j. o not use a welding power source for pipe thawing.

iv
SA ETY
iv
PRÉCAUTIONS DE SÛRETÉ
Pour votre propre protection lire et observer toutes les instructions
et les précautions de sûreté specifiques qui parraissent dans ce
manuel aussi bien que les précautions de sûreté générales suiv-
antes:
Sûreté Pour Soudage A L’Arc
1. Protegez-vous contre la secousse électrique:
a. Les circuits à l’électrode et à la piéce sont sous tension
quand la machine à souder est en marche. Eviter toujours
tout contact entre les parties sous tension et la peau nue
ou les vétements mouillés. Porter des gants secs et sans
trous pour isoler les mains.
b. Faire trés attention de bien s’isoler de la masse quand on
soude dans des endroits humides, ou sur un plancher met-
allique ou des grilles metalliques, principalement dans
les positions assis ou couché pour lesquelles une grande
partie du corps peut être en contact avec la masse.
c. Maintenir le porte-électrode, la pince de masse, le câble de
soudage et la machine à souder en bon et sûr état defonc-
tionnement.
d.Ne jamais plonger le porte-électrode dans l’eau pour le
refroidir.
e. Ne jamais toucher simultanément les parties sous tension
des porte-électrodes connectés à deux machines à souder
parce que la tension entre les deux pinces peut être le total
de la tension à vide des deux machines.
f. Si on utilise la machine à souder comme une source de
courant pour soudage semi-automatique, ces precautions
pour le porte-électrode s’applicuent aussi au pistolet de
soudage.
2. ans le cas de travail au dessus du niveau du sol, se protéger
contre les chutes dans le cas ou on recoit un choc. Ne jamais
enrouler le câble-électrode autour de n’importe quelle partie du
corps.
3. Un coup d’arc peut être plus sévère qu’un coup de soliel, donc:
a. Utiliser un bon masque avec un verre filtrant approprié ainsi
qu’un verre blanc afin de se protéger les yeux du rayon-
nement de l’arc et des projections quand on soude ou
quand on regarde l’arc.
b. Porter des vêtements convenables afin de protéger la peau
de soudeur et des aides contre le rayonnement de l‘arc.
c. Protéger l’autre personnel travaillant à proximité au
soudage à l’aide d’écrans appropriés et non-inflammables.
4. es gouttes de laitier en fusion sont émises de l’arc de
soudage. Se protéger avec des vêtements de protection libres
de l’huile, tels que les gants en cuir, chemise épaisse, pan-
talons sans revers, et chaussures montantes.
5. Toujours porter des lunettes de sécurité dans la zone de
soudage. Utiliser des lunettes avec écrans lateraux dans les
zones où l’on pique le laitier.
6. Eloigner les matériaux inflammables ou les recouvrir afin de
prévenir tout risque d’incendie dû aux étincelles.
7. Quand on ne soude pas, poser la pince à une endroit isolé de
la masse. Un court-circuit accidental peut provoquer un
échauffement et un risque d’incendie.
8. S’assurer que la masse est connectée le plus prés possible de
la zone de travail qu’il est pratique de le faire. Si on place la
masse sur la charpente de la construction ou d’autres endroits
éloignés de la zone de travail, on augmente le risque de voir
passer le courant de soudage par les chaines de levage,
câbles de grue, ou autres circuits. Cela peut provoquer des
risques d’incendie ou d’echauffement des chaines et des
câbles jusqu’à ce qu’ils se rompent.
9. Assurer une ventilation suffisante dans la zone de soudage.
Ceci est particuliérement important pour le soudage de tôles
galvanisées plombées, ou cadmiées ou tout autre métal qui
produit des fumeés toxiques.
10. Ne pas souder en présence de vapeurs de chlore provenant
d’opérations de dégraissage, nettoyage ou pistolage. La
chaleur ou les rayons de l’arc peuvent réagir avec les vapeurs
du solvant pour produire du phosgéne (gas fortement toxique)
ou autres produits irritants.
11. Pour obtenir de plus amples renseignements sur la sûreté, voir
le code “Code for safety in welding and cutting” CSA Standard
W 117.2-1974.
PRÉCAUTIONS DE SÛRETÉ POUR
LES MACHINES À SOUDER À
TRANS ORMATEUR ET À
REDRESSEUR
1. Relier à la terre le chassis du poste conformement au code de
l’électricité et aux recommendations du fabricant. Le dispositif
de montage ou la piece à souder doit être branché à une
bonne mise à la terre.
2. Autant que possible, I’installation et l’entretien du poste seront
effectués par un électricien qualifié.
3. Avant de faires des travaux à l’interieur de poste, la debranch-
er à l’interrupteur à la boite de fusibles.
4. Garder tous les couvercles et dispositifs de sûreté à leur place.
Mar. ‘93

vv
TThhaannkk YYoouufor selecting a QUALITY product by Lincoln Electric. We want you
to take pride in operating this Lincoln Electric Company product •••
as much pride as we have in bringing this product to you!
Read this Operators Manual completely before attempting to use this equipment. Save this manual and keep it
handy for quick reference. Pay particular attention to the safety instructions we have provided for your protection.
The level of seriousness to be applied to each is explained below:
WARNING
This statement appears where the information must be followed exactly to avoid serious personal injury or loss of life.
This statement appears where the information must be followed to avoid minor personal injury or damage to this equipment.
CAUTION
Please Examine Carton and Equipment or Damage Immediately
When this equipment is shipped, title passes to the purchaser upon receipt by the carrier. Consequently, Claims
for material damaged in shipment must be made by the purchaser against the transportation company at the time
the shipment is received.
Please record your equipment identification information below for future reference. This information can be found
on your machine nameplate.
Product _________________________________________________________________________________
Model Number ___________________________________________________________________________
Code Number or ate Code_________________________________________________________________
Serial Number____________________________________________________________________________
ate Purchased___________________________________________________________________________
Where Purchased_________________________________________________________________________
Whenever you request replacement parts or information on this equipment, always supply the information you
have recorded above. The code number is especially important when identifying the correct replacement parts.
On-Line Product Registration
- Register your machine with Lincoln Electric either via fax or over the Internet.
• For faxing: Complete the form on the back of the warranty statement included in the literature packet
accompanying this machine and fax the form per the instructions printed on it.
• For On-Line Registration: Go to our
WEB SITE at www.lincolnelectric.com. Choose “Quick Links” and then
“Product Registration”. Please complete the form and submit your registration.
CUSTOMER ASSISTANCE POLICY
The business of The Lincoln Electric Company is manufacturing and selling high quality welding equipment, consumables, and cutting equip-
ment. Our challenge is to meet the needs of our customers and to exceed their expectations. On occasion, purchasers may ask Lincoln Electric
for advice or information about their use of our products. We respond to our customers based on the best information in our possession at that
time. Lincoln Electric is not in a position to warrant or guarantee such advice, and assumes no liability, with respect to such information or
advice. We expressly disclaim any warranty of any kind, including any warranty of fitness for any customer’s particular purpose, with respect
to such information or advice. As a matter of practical consideration, we also cannot assume any responsibility for updating or correcting any
such information or advice once it has been given, nor does the provision of information or advice create, expand or alter any warranty with
respect to the sale of our products.
Lincoln Electric is a responsive manufacturer, but the selection and use of specific products sold by Lincoln Electric is solely within the control
of, and remains the sole responsibility of the customer. Many variables beyond the control of Lincoln Electric affect the results obtained in
applying these types of fabrication methods and service requirements.
Subject to Change – This information is accurate to the best of our knowledge at the time of printing. Please refer to www.lincolnelectric.com
for any updated information.

TABLE O CONTENTS
Page.
Installation ..........................................................................................................Section A
Technical Specifications ........................................................................................A-1,A-2
Safety Precautions.. ............................................................................................................................................... .A-3
Select Suitable Location........................................................................................A-3
Grinding .................................................................................................................A-3
Stacking.................................................................................................................A-3
Undercarriage Lifting and Moving .........................................................................A-3
Tilting .....................................................................................................................A-3
Environmental Rating ............................................................................................A-3
Machine Grounding and High FREQUENCY INTERFERENCE PROTECTION ..................A-3, A-4
Input and Grounding Connections ..............................................................................A-4
Output Cable, Connections and Limitations ................................................................A-5
Work Cable Connection ..................................................................................A-5
Stick Electrode Cable Connection ..................................................................A-5
TIG Torch Connection .....................................................................................A-6
Auxiliary Power Connections ..........................................................................A-7
Remote Control (If Used) ................................................................................A-7
Robotic Interface Connection ..................................................................A-7, A-8
________________________________________________________________________
OPERATION .........................................................................................................................................................Section B-1
Safety Precautions.......................................................................................................B-1
Product escription......................................................................................................B-1
Pipe Thawing.........................................................................................................B-1
uty Cycle: ............................................................................................................B-1
Recommended Processes and Equipment ...........................................................B-2
Controls and Settings ..........................................................................B-3 THRU B-6
Internal Set Up Controls ........................................................................................B-7
Stick Welding Features..........................................................................................B-7
TIG Welding Features ...........................................................................................B-7
2 Step Trigger Modes......................................................................................B-8
4 Step Trigger Modes ....................................................................................B-9
TIG Welding Cycle Chart ....................................................................................B-10
Setup Guidelines for TIG Welding with an Amptrol.....................................B-10, B11
Making a TIG Weld with an Amptrol....................................................................B-12
________________________________________________________________________
Accessories ............................................................................................................................................... .......Section C
Optional Equipment .....................................................................................................C-1
________________________________________________________________________
Maintenance......................................................................................................................................................Section
Safety Precautions....................................................................................................... -1
Routine and Periodic Maintenance.............................................................................. -1
Overload Protection ..................................................................................................... -1
Service Procedures, Component Access,Spark Gap Adjustment ............................... -2
Under-Cooler Service .................................................................................................. -2
________________________________________________________________________
Troubleshooting.............................................................................................................................................Section E
Safety Precautions.......................................................................................................E-1
How To Use TroubleShooting Guide............................................................................E-1
Troubleshooting.................................................................................................E-2 to E-7
________________________________________________________________________
Diagrams..............................................................................................................................................................Section F
Wiring iagrams..............................................................................................................................................F-1, F-2
imension Prints .............................................................................................................................................F-3, F-4
________________________________________________________________________
Parts List......................................................................................................................................................................P-543
vivi

A-1
INSTALLATION
PRECISION TIG 375
A-1
TECHNICAL SPECI ICATIONS- PRECISION TIG 375 (K2623-1 Export-50/60Hz)
Voltage + 10%
220-230/
380-400/415
Max. Amps With Power actor Capacitor
119/69/63
118/68/62
110/64/59
97/56/52
88/51/47
73/42/39
48/28/25
.67 min.
.8KW
Duty Cycle-Applications
40%
AC/ C Stick / Balance TIG
Unbalance (70% Penetration#) AC TIG
60%
AC/ C Stick / Balance TIG
Unbalance (70% Penetration#) AC TIG
100%
AC/ C Stick / Balance TIG
Unbalance (70% Penetration#) AC TIG
Idle Amps
Rated Power Factor (Stick)
Idle Power
RATED INPUT - SINGLE PHASE ONLY
#Exceeds NEMA Unbalanced Load Specification comparable for Auto-Balance.
*50/60HZIEC Max. range exceeds 310A.
ADDITIONAL OUTPUT CAPACITY
Output Current
Range
2Amps C
to
420Amps AC- C*
Type of Output
CC (Constant Current)
AC/ C (GTAW)
Stick (SMAW)
Maximum Open
Circuit Voltage
(STICK AN TIG)
AC/ C OCV: 80
Auxiliary Power
5 Amp Circuit Breaker
and grounded 220VAC
Euro(Schuko) receptacle
RATED OUTPUT - IEC 60974-1
Duty Cycle-Applications
40%
AC/ C Stick / Balance TIG
Unbalance (70% Penetration#) AC TIG
60%
AC/ C Stick / Balance TIG
Unbalance (70% Penetration#) AC TIG
100%
AC/ C Stick / Balance TIG
Unbalance (70% Penetration#) AC TIG
Volts at Rated Amperes
35.0
24.0
34.0
23.0
32.0
21.0
Amps
375
350
350
325
300
275

A-2
INSTALLATION
PRECISION TIG 375
A-2
Height Width Depth Weight
31.0 in. 22.0 in. 26.0 in. 507 lbs.
787 mm 559 mm 660 mm 230 kgs.
PHYSICAL DIMENSIONS
1ALSO CALLE ‘INVERSE TIME" OR "THERMAL/MAGNETIC " CIRCUIT BREAKERS; CIRCUIT BREAKERS WHICH HAVE A ELAY IN TRIPPING ACTION THAT ECREASES AS
THE MAGNITU E OF CURRENT INCREASES.
TEMPERATURE RANGES
OPERATING TEMPERATURE RANGE
-20°C to +40°C (-04° to +104°F)
TRANS ORMER INSULATION CLASS 180°C (H)
STORAGE TEMPERATURE RANGE
-40°C to +85°C (-40° to +185°F)
or all Stick, DC TIG, and Balanced AC TIG Welding
at 375A/40% Duty Cycle with out Standard Power
actor Correction Capacitors
Based on the 1999 U.S. National Electrical Code
or Unbalanced AC TIG Welding Above 275 Amps:
350A/40% Duty Cycle, Auto-Balance Penetration with
out Standard Power actor Correction Capacitors
Based on the 1999 U.S. National Electrical Code
RECOMMENDED INPUT WIRE AND USE SIZES
Input
Voltage /
phase/
requency
220-230/1/50/60
380-400/1/50/60
415/1/50/60
Input
Ampere
Rating
Rating on
Nameplate
119
69
63
Input
Ampere
Rating
118
68
62
Type 75°C
Copper
Ground Wire in
Conduit AWG
(IEC) Sizes
6 (13.3 mm2)
6 (13.3 mm2)
6 (13.3 mm2)
Type 75°C
Copper
Ground Wire in
Conduit AWG
(IEC) Sizes
6 (13.3 mm2)
6 (13.3 mm2)
6 (13.3 mm2)
use
(Super Lag)
or Breaker
Size1
150
110
110
use
(Super Lag)
or Breaker
Size1
150
110
110
Type 75°C
Copper Wire in
Conduit AWG
(IEC) Sizes
40°C (104° )
Ambien
3 (26.7 mm2)
4 (21.2 mm2)
4 (21.2 mm2)
Type 75°C
Copper Wire in
Conduit AWG
(IEC) Sizes
40°C (104° )
Ambient
3 (26.7 mm2)
4 (21.2 mm2)
4 (21.2 mm2)

A-3
INSTALLATION
PRECISION TIG 375
A-3
SA ETY PRECAUTIONS
SELECT SUITABLE LOCATION
Place the welder where clean cooling air can freely cir-
culate in through the top rear vents and out through the
bottom rear vents. irt, dust or any foreign material
that can be drawn into the welder should be kept at a
minimum. Failure to observe these precautions can
result in excessive operating temperatures and nui-
sance trips.
GRINDING
o not direct grinding particles towards the welder. An
abundance of conductive material can cause mainte-
nance problems.
STACKING
The Precision TIG 375's cannot be stacked .
UNDERCARRIAGE LI TING AND MOVING
When the Precision TIG 375 is purchased as a weld-
ing package, or used with any of the available
Undercarriage optional accessories, proper installation
makes the Precision TIG 375 lift bale nonfunctional.
o not attempt to lift the power source with an under-
carriage attached. The undercarriage is designed for
hand moving only; mechanized movement can lead to
personal injury and/or damage to the Precision TIG
375.
TILTING
Each machine must be placed on a secure, level sur-
face, either directly or on a recommended undercar-
riage. The machine may topple over if this precaution
is not followed.
ENVIRONMENTAL RATING
Precision TIG 375 power sources carry an IP21S
Environmental rating. They are rated for use in damp,
dirty rain-sheltered environments.
MACHINE GROUNDING AND HIGH RE-
QUENCY INTER ERENCE PROTECTION
The frame of the welder must be grounded. A ground screw
marked with the symbol is located on the input connection
panel (Figure A.1) for this purpose. See your local and nation-
al electrical codes for proper grounding methods.
The spark gap oscillator in the high frequency genera-
tor, being similar to a radio transmitter, can be blamed
for many radio, TV and electronic equipment interfer-
ence problems. These problems may be the result of
radiated interference. Proper grounding methods can
reduce or eliminate radiated interference.
The Precision TIG 375 has been field tested under rec-
ommended installation conditions and has been found
to comply with F.C.C. allowable radiation limits. This
welder has also been found to comply with NEMA stan-
dards for high frequency stabilized power sources.
Radiated interference can develop in the following four
ways:
• irect interference radiated from the welder.
• irect interference radiated from the welding leads.
• irect interference radiated from feedback into the
power lines.
• Interference from re-radiation of "pickup" by
ungrounded metallic objects.
Keeping these contributing factors in mind, installing
the equipment per the following instructions should
minimize problems:
1. Keep the welder power supply lines as short as pos-
sible. Input leads within 50 feet (15.2 m) of the
welder should be enclosed in rigid metallic conduit
or equivalent shielding. There must be good electri-
cal contact between this conduit and the welder.
Both ends of the conduit must be connected to a
driven ground and the entire length must be contin-
uous.
2. Keep the work and electrode leads as short as pos-
sible and as close together as possible. Lengths
should not exceed 25 feet (7.6 m). Tape the leads
together when practical.
Read entire installation section before starting
installation.
ELECTRIC SHOCK can kill.
•Only qualified personnel should
perform this installation.
• Turn the input power O at the
disconnect switch or fuse box
before working on this
equipment.
• Do not touch electrically hot
parts.
• Always connect the Precision TIG 375 grounding screw (behind
the reconnect panel cover located near the back of the left case
side) to a good electrical earth ground.
• Always connect the Precision TIG 375 to a power supply
grounded in accordance with the National Electrical Code and
all local codes.
WARNING