Lincoln Electric SVM162-B User Manual

PRECISION TIG 275

RETURN TO MAIN MENU

SVM162-B

January, 2008

For use with machines having Code Numbers:

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 SAFETY PRECAUTIONS CONTAINED THROUGHOUT.

And, most importantly, think before you act and be careful.

10806; 10807; 10893; 11158; 11159

View Safety Info View Safety Info View Safety Info View Safety Info

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Cleveland, Ohio 44117-1199 U.S.A. TEL: 888-935-3877 FAX: 216.486.1751 WEB SITE: www.lincolnelectric.com

SERVICE MANUAL

• World's Leader in Welding and Cutting Products •

• Sales and Service through Subsidiaries and Distributors Worldwide •

ii ii

SAFETY

WARNING

CALIFORNIA PROPOSITION 65 WARNINGS

Diesel engine exhaust and some of its constituents are known to the State of California to cause cancer, birth defects, and other reproductive harm.

The Above For Diesel Engines

ARC WELDING can be hazardous. PROTECT YOURSELF AND OTHERS FROM POSSIBLE SERIOUS INJURY OR DEATH.

KEEP CHILDREN AWAY. PACEMAKER WEARERS SHOULD CONSULT WITH THEIR DOCTOR BEFORE 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 PERFORMED ONLY BY QUALIFIED INDIVIDUALS.

The engine exhaust from this product contains chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm.

The Above For Gasoline Engines

FOR 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. Do not add the fuel near an open flame welding arc or when the engine is running. Stop the engine and allow it to cool before refueling to prevent spilled fuel from vaporizing on contact with hot engine parts and igniting. Do 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 position 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. Do not put your hands near the engine fan. Do not attempt to override the governor or idler by pushing on the throttle control rods while the engine is running.

1.h. To avoid scalding, do not remove the radiator pressure cap when the engine is hot.

ELECTRIC AND MAGNETIC FIELDS 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. Do 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.

___________________________________________________

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.

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

2.d.4. Connect the work cable to the workpiece as close as possible to the area being welded.

2.d.5. Do not work next to welding power source.

Mar ʻ95

iiii iiii

SAFETY

ELECTRIC SHOCK can kill.

3.a. The electrode and work (or ground) circuits are electrically “hot” when the welder is on. Do 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.

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.

FUMES 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 exposure level should be checked upon installation and periodically thereafter to be certain it is within applicable OSHA PEL and ACGIH TLV limits.

5.c.

Do not weld in locations near chlorinated hydrocarbon coming from degreasing, cleaning or spraying operations. The heat and rays of the arc can react with solvent vapors form phosgene, a highly toxic gas, and other irritating products.

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.

vapors

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

5.e. Read and understand the manufacturerʼs instructions for this

equipment and the consumables to be used, including the material safety data sheet (MSDS) and follow your employerʼs safety practices. MSDS forms are available from your welding distributor or from the manufacturer.

5.f. Also see item 1.b.

Aug ʻ06

iiiiii iiiiii

SSAAFFEETTYY

WELDING 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.

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. Do 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 been “cleaned”. For information, purchase “Recommended Safe Practices for the 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.

Sparks and spatter are thrown from the welding arc. Wear oil

6.f. 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.

Remember that welding sparks and hot

though

they have

Preparation

for Welding and Cutting of

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 Davis Highway, Arlington, VA 22202.

FOR 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 manufacturerʼs recommendations.

8.c. Ground the equipment in accordance with the U.S. National Electrical Code and the manufacturerʼs recommendations.

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Mar ʻ95

iivv iivv

SSAAFFEETTYY

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 suivantes:

Sûr

eté Pour Soudage A L’Arc

1. Protegez-vous contre la secousse électrique:

Les circuits à lʼélectrode et à la piéce sont sous tension

quand la machine à souder est en marche. Eviter toujours tout contact ou les vétements mouillés. Porter des gants secs et sans trous pour isoler les mains.

b. Faire trés attention de bien sʼisoler de la masse quand on

soude dans des endroits humides, ou sur un plancher metallique 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 defonctionnement.

d.Ne jamais plonger le porte-électrode dans lʼeau 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 sʼapplicuent aussi au pistolet de soudage.

entre les parties sous tension et la peau nue

6. Eloigner les matériaux inflammables ou les recouvrir afin de prévenir tout risque dʼincendie 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 dʼincendie.

8. Sʼassurer que la masse est connectée le plus prés possible de la zone de travail quʼil est pratique de le faire. Si on place la masse sur la charpente de la construction ou dʼautres 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 dʼincendie ou dʼechauffement des chaines et des câbles jusquʼà ce quʼils 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 dʼopérations de dégraissage, nettoyage ou pistolage. La chaleur ou les rayons de lʼarc 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.

2. Dans 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 nʼimporte quelle partie du corps.

3. Un coup dʼarc peut être plus sévère quʼun coup de soliel, donc:

a. Utiliser un bon masque avec un verre filtrant approprié ainsi

quʼun verre blanc afin de se protéger les yeux du rayonnement de lʼarc et des projections quand on soude ou quand on regarde lʼarc.

b. Porter des vêtements convenables afin de protéger la peau

de soudeur et des aides contre le rayonnement de lʻarc.

c. Protéger lʼautre personnel travaillant à proximité au

soudage à lʼaide dʼécrans appropriés et non-inflammables.

4. Des gouttes de laitier en fusion sont émises de lʼarc de soudage. Se protéger avec des vêtements de protection libres de lʼhuile, tels que les gants en cuir, chemise épaisse, pantalons 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 lʼon pique le laitier.

PRÉCAUTIONS DE SÛRETÉ POUR LES MACHINES À SOUDER À TRANSFORMATEUR ET À REDRESSEUR

1. Relier à la terre le chassis du poste conformement au code de lʼélectricité 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, Iʼinstallation et lʼentretien du poste seront effectués par un électricien qualifié.

3. Avant de faires des travaux à lʼinterieur de poste, la debrancher à lʼinterrupteur à la boite de fusibles.

4. Garder tous les couvercles et dispositifs de sûreté à leur place.

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Mar ʻ93

MASTER TABLE OF CONTENTS FOR ALL SECTIONS

RETURN TO MAIN MENU

RETURN TO MAIN INDEX

Safety .................................................................................................................................................i-iv

Installation.............................................................................................................................Section A

Operation...............................................................................................................................Section B

Accessories ..........................................................................................................................Section C

Maintenance..........................................................................................................................Section D

Theory of Operation .............................................................................................................Section E

Troubleshooting and Repair ................................................................................................Section F

How to Use Troubleshooting Guide ............................................................................................F-2

Safety Precautions ......................................................................................................................F-3

Troubleshooting Guide ................................................................................................................F-4

Test Procedures ........................................................................................................................F-19

Oscilloscope Waveforms...........................................................................................................F-39

Replacement Procedures .........................................................................................................F-45

Retest After Repair....................................................................................................................F-61

Page

Electrical Diagrams ..............................................................................................................Section G

Parts Manual ........................................................................................................P404 & P558 Series

PRECISION TIG 275

TABLE OF CONTENTS

- INSTALLATION SECTION -

Installation

Technical Specifications..............................................................................................................A-2

Rated Output...............................................................................................................................A-3

Additional Output Capacity .........................................................................................................A-3

Wire and Fuse Sizes...................................................................................................................A-3

Physical Dimensions...................................................................................................................A-3

Temperature Ranges ..................................................................................................................A-3

Safety Precautions......................................................................................................................A-4

Stacking ......................................................................................................................................A-4

Lifting and Moving.......................................................................................................................A-4

Tilting...........................................................................................................................................A-4

High Frequency Interference Protection .....................................................................................A-4

A-1A-1

Input Electrical Connections .......................................................................................................A-5

Ground Connection...............................................................................................................A-5

Output Cables, Connections & Limitations .................................................................................A-6

TIG Torch Connection .................................................................................................................A-7

Auxiliary Power Connections ......................................................................................................A-8

Remote Control...........................................................................................................................A-8

Robotic Interface Connection .....................................................................................................A-9

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

A-2

N80

INSTALLATION

A-2

TECHNICAL SPECIFICATIONS-

RATED INPUT - SINGLE PHASE ONLY

Number

K1825-1 K1826-1 K2619-1

NRTL/C

K1826-2 K2619-2

NRTL/C

K1827-1

IEC 60974-1

Duty Cycle-Applications

40%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration

60%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration

100%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

Idle Amps

40%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration

60%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

100%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

Idle Amps

Idle Power

40%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

60%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

100%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

Idle Amps

Idle Power

) AC TIG

PRECISION TIG 275 (Domestic, Canadian & Export

Voltage + 10%

208/230/460

460/575

220-230/

380-400/415

Max. Amps With Out

Power Factor Capacitor

104/94/47

124/112/56

86/78/39 95/86/43

77/70/35 73/66/33

6/5/3

47/38 56/45

39/31 43/35

35/28 33/26

3/2

300W

95/55/50

109/63/58

80/46/42 85/49/45

70/41/37 65/38/35

10/6/5

400W

Max. Amps With

Power Factor Capacitor

80/72/36 95/86/43

64/58/29 62/56/28

55/50/25 40/36/18 36/32/16

35/28 43/34

29/23 28/23

25/20 18/14 16/13 500W

80/46/43 86/50/46

64/37/34 67/39/36

52/30/28 46/27/25 23/13/12

500W

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

RATED POWER FACTOR (STICK)

K1825-1,K1826-1 & K1826-2 .63 min. .85 min. K1827-1 .65 min. .77 min.

RATED OUTPUT - NEMA EW1 Class ll (40) K1825-1,K1826-1,-2, K2619-1.-2

Duty Cycle-Applications

40%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration

) AC TIG

60%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

100%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration

*Shown on Front of this IM manual with Under-Cooler Cart and Advanced Control Panel (Refer to Optional Equipment)

Exceeds NEMA Unbalanced Load Specification comparable for Auto-Balance.

) AC TIG

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Volts at Rated Amperes

31.0

16.1

29.0

15.4

28.0

14.8

PRECISION TIG 275

Amps

275 255

225 200

200 150

A-3

RATED OUTPUT - IEC 60974-1 (K1827-1)

Duty Cycle-Applications

40%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration#) AC TIG

60%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration

) AC TIG

100%

AC/DC Stick / Balance TIG

Unbalance (70% Penetration

Output Current

Range

Maximum Open

Circuit Voltage

) AC TIG

2Amps DC

340Amps AC-DC

(STICK AND TIG)

AC/DC OCV: 75/68

RECOMMENDED INPUT WIRE AND FUSE SIZES

For all Stick, DC TIG, and Balanced AC TIG Welding

at 275A/40% Duty Cycle with out Standard Power

Factor Correction Capacitors

Based on the 1999 U.S. National Electrical Code

Input

Voltage /

phase/

Frequency

208/1/60

230/1/60

460/1/60

575/1/60

220-230/1/50/60

380-400/1/50/60

415/1/50/60

Fuse

(Super Lag)

or Breaker

Size

125

Input

Ampere

Rating

Rating on

Nameplate

104

Copper Wire in

Conduit AWG

40°C (104°F)

4 (21.2 mm2)

10 (5.3mm

4 (21.2 mm2)

INSTALLATION

Volts at Rated Amperes

31.0

20.2

29.0

18.0

28.0

16.0

ADDITIONAL OUTPUT CAPACITY

Type of Output

15Amp Circuit Breaker and NEMA 5-15R Duplex

CC (Constant Current)

AC/DC (GTAW)

Stick (SMAW)

Type 75°C

(IEC) Sizes

Ambient

8 (8.4mm

Type 75°C

Ground Wire in

Conduit AWG

(IEC) Sizes

6 (13.3 mm2)

10 (5.3mm

6 (13.3 mm2)

8 (8.4mm

255A/40% Duty Cycle, Auto-Balance Penetration with

Copper

(Super Lag)

or Breaker

115VAC 8Amp Auxiliary Power Receptacle

115VAC weld Switched Cooler Receptacle load

For Unbalanced AC TIG Welding Above 275 Amps:

out Standard Power Factor Correction Capacitors

Based on the 1999 U.S. National Electrical Code

Fuse

Size

150

Amps

Auxiliary Power

K1825-1, K1826-1, K1826-2

Receptacle for up to:

K1834-1

5 Amp Circuit Breaker

and grounded 220VAC

Euro(Schuko) receptacle

Type 75°C

Input

Ampere

Rating

124

112

109

Copper Wire in

Conduit AWG

(IEC) Sizes

40°C (104°F)

Ambient

3 (26.7 mm2)

8 (8.4 mm

4 (21.2 mm2)

6 (13.3 mm

275 255

225 200

200 150

Type 75°C

Copper

Ground Wire in

Conduit AWG

(IEC) Sizes

6 (13.3 mm2)

8 (8.4 mm

10 (5.3mm

6 (13.3 mm2)

8 (8.4 mm

A-3

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

K1826-1, -2

K1827-1

K2619-1,-2

K1825-1

Height Width Depth Weight

31.0 in. 22.0 in. 26.0 in. Approx. 397 lbs. 787 mm 559 mm 660 mm 180 kgs.

49.7 in. 28.0 in. 41.0 in. Approx.641 lbs. 1262 mm 711 mm 1041 mm 291 kgs.

OPERATING TEMPERATURE RANGE

-20°C to +40°C (-04° to +104°F)

TRANSFORMER INSULATION CLASS 180°C (H)

ALSO CALLED ʻINVERSE TIME" OR "THERMAL/MAGNETIC " CIRCUIT BREAKERS; CIRCUIT BREAKERS WHICH HAVE A DELAY IN TRIPPING ACTION THAT DECREASES AS

THE MAGNITUDE OF CURRENT INCREASES.

* 50/60HZ IEC Max. range exceeds 310A.

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PHYSICAL DIMENSIONS

TEMPERATURE RANGES

STORAGE TEMPERATURE RANGE

-40°C to +85°C (-40° to +185°F)

PRECISION TIG 275

A-4

INSTALLATION

A-4

SAFETY PRECAUTIONS

Read entire Installation Section before installing the Precision Tig 275.

WARNING

ELECTRIC SHOCK can kill.

• Only qualified personnel should per-

form this installation.

• Turn the input power OFF

at the disconnect switch or

fuse box and discharge input capacitors

before working inside the equipment.

• Do not touch electrically hot parts.

• Always connect the Precision Tig 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 to a power supply grounded

in accordance with the National Electrical Code and all local

codes.

SELECT SUITABLE LOCATION

Place the welder where clean cool air can freely circulate in through the rear louvers and out through the bottom opening. Dirt, dust or any foreign material that can be drawn into the machine should be kept at a minimum. Failure to observe these precautions can result in excessive operating temperatures and nuisance trips.

The machine may topple over if this precaution is not followed.

ENVIRONMENTAL RATING

Precision TIG 275 power sources carry an IP21S Environmental rating. They are rated for use in damp, dirty rain-sheltered environments.

HIGH FREQUENCY INTERFERENCE 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 national electrical codes for proper grounding methods.

The spark gap oscillator in the high frequency generator, being similar to a radio transmitter, can be blamed for many radio, TV and electronic equipment interference problems. These problems may be the result of radiated interference. Proper grounding methods can be reduced or eliminate re-radiated interference.

The Precision TIG 275 has been field tested under recommended 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 standards for high frequency stabilized power sources.

GRINDING

Do not direct grinding particles towards the welder. An abundance of conductive material can cause maintenance problems.

STACKING

The Precision Tig 275 cannot be stacked.

UNDERCARRIAGE LIFTING AND MOVING

When the Precision TIG 275 is purchased as a welding package, or used with any of the available Undercarriage optional accessories, proper installation makes the Precision TIG 275 lift bale nonfunctional. Do not attempt to lift the power source with an undercarriage attached. The undercarriage is designed for hand moving only; mechanized movement can lead to personal injury and/or damage to the Precision TIG

275.

TILTING

Each machine must be placed on a secure, level surface, either directly or on a recommended undercarriage.

Radiated interference can develop in the following four ways: * Direct interference radiated from the welder. * Direct interference radiated from the welding leads. * Direct interference radiated from the 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 possible and completely enclose them in rigid metallic conduit or equivalent shielding for a minimum distance of 50 feet (15.2 m). There must be good electrical contact between this conduit must be connected to a driven ground and the entire length must be continuous.

2. Keep the work and electrode leads as short as possible and as close together as possible. Lengths should not exceed 25 feet (7.6m). Tape the leads together when practical.

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

PRECISION TIG 275

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

A-5

INSTALLATION

A-5

3. Be sure the torch and work cable rubber coverings are free of cuts and cracks that allow high frequency leakage. Cables with high natural rubber content,

such as Lincoln Stable-Arc

better resist high frequency leakage than neoprene and other synthetic rubber insulated cables.

4. Keep the torch in good repair and all connections tight to reduce high frequency leakage.

5. The work terminal must be connected to a ground* within ten feet of the welder, using one of the following methods.

* A metal underground water pipe in direct contact

with the earth for ten feet or more.

* A 3/4” (19mm) galvanized pipe or a 5/8” (16mm)

solid galvanized iron, steel or copper rod driven at least eight feet into the ground.

The ground should be securely made and the grounding cable should be as short as possible using cable of the same size as the work cable, or larger. Grounding to the building frame electrical conduit or a long pipe system can result in re-radiation, effectively making these members radiating antennas. (This is not recommended.)

6. Keep all access panels and covers securely in place.

7. All electrical conductors within 50 feet (15.2m) of the welder should be enclosed in grounded rigid metallic conduit or equivalent shielding. Flexible helicallywrapped metallic conduit is generally not suitable.

8. When the welder is enclosed in a metal building, several earth driven electrical grounds (as in 5 above) around the periphery of the building are recommended.

Failure to observe these recommended installation procedures can cause radio or TV interference problems and result in unsatisfactory welding performance resulting from lost high frequency power.

INPUT and GROUNDING CONNECTIONS

WARNING

ELECTRIC SHOCK can kill.

* Turn the input power OFF at the

disconnect switch or fuse box before working on this equipment.

___________________________________________

Be sure the voltage, phase, and frequency of the input power is as specified on the rating plate, located on the rear of the machine.

Fuse the input circuit with the recommended super lag fuses or delay type1 circuit breakers. Choose an input and grounding wire size according to local or national codes or use Section A-2. Using fuses or circuit breakers smaller than recommended may result in “nuisance” tripping from welder inrush currents even if not welding at high currents.

Unbalanced AC TIG welding draws higher input currents than those for Stick, DC TIG, or Balanced AC TIG welding. The welder is designed for these higher input currents. However, where unbalanced AC TIG welding above 185 amps is planned, the higher input currents require larger input wire sizes and fuses per Section A-2:

Remove the reconnect panel cover located near the back of the left case side to reveal the reconnected panel. Welder supply line entry provision is in the case rear panel. Entry is through a 1.75 inch (44mm) diameter hole in the case back. Appropriate supply line strain relief clamp is provided by installer. (See Figure A.1)

All connections should be made in accordance

FIGURE A.1

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

CONNECT INPUT POWER LEADS

CONNECT INPUT GROUND LEAD

with all local codes and national electrical codes. Installation by a qualified electrician is recommended.

PRECISION TIG 275

CONNECT INPUT VOLTAGE LEVEL

A-6

INSTALLATION

A-6

1. Connect the terminal marked (below the reconnect panel) to an earth ground.

2. Connect the input leads to terminals marked L1 (U) and L2 (V) on the reconnect panel. Use a single phase line or one phase of a two or three phase line.

3. On multiple input voltage welders, be sure the reconnect panel is connected for the voltage being supplied to the welder.

CAUTION

Failure to follow these instructions can cause immediate failure of components within the welder.

------------------------------------------------------------------------

Welders are shipped connected for the highest input voltage as listed on the rating plate. To change this connection, designations on the reconnect panel LOW, MID, and HIGH correspond to the name plated input voltages of a triple voltage welder. Dual voltage welders use only LOW and HIGH.

Recommended Cable Sizes for Combined Lengths of Copper Work and Electrode Cables using 75

Machine Rating 0 to 100 Ft. 101 to 200 Ft 201 to 250 Ft

275A/40% #1 (42.4 mm2) 1/0 (53.5 mm2) 2/0 (67.4 mm2)

C Wire:

WORK CABLE CONNECTION

A 15ʼ (2/0) weld cable with clamp is available (K2150-1), or included with the Precision TIG Welding Package model. Otherwise, it is user provided.

With power source off, connect a separate work cable to the 1/2-13 threaded "WORK" stud of the welder, and secure a tight connection with the flange nut provided. The work cable should be routed through the cable strain relief hole provided in the base directly below the welding output terminal. Note: If the Precision TIG is equipped with an UnderCooler or Under-Storage unit, the coiled work cable and clamp, or excess work cable length, may be conveniently stored in the drawer while remaining connected.

EXAMPLE: On a 208/230/460 volt welder, LOW is 208V, MID is 230V, and HIGH is 460V.

NOTE: Export model has a voltage range for LOW and

MID connections: LOW is 220-230V, MID is 280400V and high is 415V.

Reconnect the jumper strap to the terminal stud corresponding to the input voltage level used. Make sure all connections are tight.

WARNING

OUTPUT CABLES, CONNECTIONS AND LIMITATIONS

• To avoid being startled by a high frequency

shock, keep the TIG torch and cables in good condition

• Turn the power switch of the power source OFF

before installing adapters on cable or when connecting or disconnecting adapter plugs to power source.

-----------------------------------------------------------------------

STICK ELECTRODE CABLE CONNECTION

If manual stick welding is desired, with power source off, connect a stick electrode cable to the 1/2-13 threaded "STICK Electrode" stud of the welder, and secure a tight connection with the flange nut provided. The electrode cable should be routed through the cable strain relief hole provided in the base directly below the welding output terminal.

WARNING

DISCONNECT STICK ELECTRODE WELDING CABLE WHEN TIG WELDING.

EVEN THOUGH HI-FREQ IS NOT APPLIED TO THE PRECISION TIG STICK TERMINAL, IT WILL BE ELECTRICALLY "HOT" TO WORK WHEN TIG WELDING.

------------------------------------------------------------------------

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Refer to Figure A.2 for the location of the WORK and STICK terminals, as well as the TIG Torch connection panel.

PRECISION TIG 275

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

A-7

ORK

TICK

ORK

TICK

STICK

ELECTRODE

STUD

WORK

STUD

TIG TORCH

CONNECT IO

PANEL

FIGURE A

(Shown without hinged stud cover)

REMOTE

CONTROL

RECEPTACLE

CABLE

STRAIN

RELIEF H OLES

INSTALLATION

FIGURE A.2

A-7

TIG TORCH CONNECTION

The Precision TIG torch connection box, located on the right side of the machine, provides all the input and output connections for the installation of both aircooled and water-cooled TIG torches with fittings conforming to Compressed Gas Association (CGA) standards: Note: The Precision TIG provides an insulated Torch Reel and Holster for handy and safe storage of connected torch when not welding, and excess torch cable length while welding.

WARNING

Combination connectors (Power/Water and Power/Gas) are electrically "hot" while welding in STICK or TIG modes.

If using an Air-Cooled Torch be sure coolant is shut off and/or Cooler is unplugged from the Precision TIG Water Cooler Receptacle on the torch side of the upper case back.

CYLINDER could explode if damaged.

• Keep cylinder upright and chained to a support.

• Keep cylinder away from areas where it could be damaged.

• Never allow the torch to touch the cylinder.

• Keep cylinder away from live electrical circuits.

• Maximum inlet pressure 150 psi.

-----------------------------------------------------------------

The Precision TIG machines do not have Hi-Freq. available at the Stick electrode stud, therefore stud connection adapters (such as LECO. S19257-series) cannot be used for torch connection.

Single-piece cable air-cooled torches with a 3/8-24 RH connector fitting (such as the Magnum PTA-9/-17, or LA9/-17) require the provided S20403-4 Torch Connector, while those with a 7/8-14 RH connector fitting (such as the Magnum PTA-26, or LA-26) require the available

K2166-1 Torch Connector. (See Figure A.3)

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Observe the safety precautions necessary for handling and using compressed gas containers. Contact your supplier for specifics.

Two-piece cable air-cooled torches (such as PTA-, or LAtorches) can be used with the available 1/2” Stud Connector (S20403-3) with with a 7/8-14 LH male fitting.

Magnum PTW-18/-20 (or LW-) water-cooled Torches require no adapter for Precision TIG connection.

PRECISION TIG 275

A-8

INSTALLATION

FIGURE A.3

A-8

For Gas Supply hose with 5/8-18RH male (Provided with Weld Package model)

For Coolant Supply Hoses with 5/8-18LH male (Provided with Weld Package model or Under-Cooler Cart)

AUXILIARY POWER CONNECTIONS

The Precision TIG machines provide a standard NEMA 5-15R duplex receptacle, located on the upper case back on the torch side of the machine:

• The bottom outlet of this duplex receptacle provides switched 115VAC power for the Under-Cooler, or Water Solenoid accessory. This Cooler receptacle turns on when the arc starts and remains on for about 8 minutes after the arc goes out (with the Fan-AsNeeded machine cooling fan, see Maintenance Section), so the Coolerʼs fan and water pump will not run continuously in idle, but will run while welding.

• The top outlet of this duplex receptacle provides at least 8 amps at 115VAC, whenever the Precision TIG Power switch is ON. This auxiliary circuit is intended for running 115VAC accessories or small power tools.

Note: Some types of equipment, especially pumps and large motors, have starting currents which are significantly higher than their running current. These higher starting currents may cause the circuit breaker to open. (See next paragraph)

• Both the receptacle circuits are protected from shorts and overloads by a 15 amp circuit breaker, located above the receptacle. if the breaker trips its button pops out exposing a red ring. When the circuit breaker cools the button can be reset by pressing it back in.

Note: When the breaker trips not only will the auxiliary and cooler power be interrupted, but so will the power to the shielding gas solenoid and machine cooling fan.

The Precision TIG Export models also provide a grounded 220 VAC Euro type Schuko receptacle and a 5 amp circuit breaker, located on the upper case back on the reconnect side of the machine, intended for use with a 220 VAC water cooler.

REMOTE CONTROL (If Used)

The Foot Amptrol (included with the Precision TIG Welding Package), or other Remote accessory, is installed by routing the plug of its control cable up through the left cable strain relief hole provided in the base (see Figure A.2), then connecting the 6-pin plug to the mating Remote receptacle behind the stud panel cover. (See Operation Section B-2 for mating plug wiring.) Note: If the Precision TIG is equipped with an UnderCooler or Under-Storage unit, the Foot Pedal (or other remote control accessory) and coiled control cable, or excess cable length, may be conveniently stored in the drawer while remaining connected.

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

PRECISION TIG 275

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

A-9

= 70Vdc max.

R = V

/ 5ma

5ma

Robotic Common

REMOTE RECEPTACLE

(Front View)

For 18-12P Plug

(LECO S12020-27)

ARC START

INPUT FROM ROBOT

(18Vac,10ma switch)

PRESET CONTROL

INPUT FROM ROBOT

(0 -10Vdc = Rated Output Range)

ARC ESTABLISHED

OUTPUT TO ROBOT

(High = Not Welding)

(Low = Welding)

* Precision TIG Control Common.

Note: The Interface connection cable may pick up noise interference. Additional bypass/filtering circuits may be needed for the external circuits.

INSTALLATION

ROBOTIC INTERFACE CONNECTION

Robotic interface can be made at the Remote Receptacle (See Operation Section). The machine is shipped with the remote receptacle circuit internally connected to receptacle J5 of the Control board for standard Amptrol operation. In order to enable the remote receptacle for robotic interface its connection plug must be moved from J5 to J5A on the Control board. (Refer to the machine Wiring Diagram.)

The robotic interface functions with the Precision TIG set to either TIG or STICK mode, but must be in REMOTE switch position for the Preset Control interface to function. When in the REMOTE position with robotic interface neither the MAXIMUM OUTPUT nor the MINIMUM OUTPUT panel controls limit the interface control setting over the rated output range of the machine.

The diagram in Figure A.4 below shows the remote receptacle plug connections and signals for robotic interface:

A-9

FIGURE A.4

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

A-10

NOTES

A-10

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

B-1

TABLE OF CONTENTS

- OPERATION SECTION -

Operation ...............................................................................................................................Section B

Safety Precautions ......................................................................................................................B-2

Product Description.....................................................................................................................B-2

Recommended Process and Equipment ....................................................................................B-3

Controls and Settings..................................................................................................................B-4

Welding Operation................................................................................................................B-5/B-8

Internal Set Up Controls..............................................................................................................B-9

2 Step Trigger Modes................................................................................................................B-10

4 Step Trigger Modes ................................................................................................................B-11

TIG Weld Cycle Chart ...............................................................................................................B-12

Set Up for TIG Amptrol Welding................................................................................................B-13

Making a TIG Weld with an Amptrol .........................................................................................B-14

Recommended Electrode Amperage Ranges...........................................................................B-14

B-1

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

B-2

OPERATION

B-2

SAFETY PRECAUTIONS

Read and understand this entire section before operating the machine.

WARNING

ELECTRIC SHOCK CAN KILL. *Only qualified personnel should per-

form the installation.

* Turn the input power OFF at the dis-

connect switch or fuse box.

* Do not touch electrically live parts or

electrode with skin or wet clothing.

* Insulate yourself from work and

ground. * Always dry insulating gloves. * Read and follow “Electric Shock

Warnings” in the Safety section if welding must be performed under electrically hazardous conditions such as welding in wet areas or on or in the workpiece.

......................................................................................

FUMES AND GASES can be dangerous. * Keep your head out of fumes. *Use ventilation or exhaust to

remove fumes from breathing zone.

......................................................................................

WELDING SPARKS can cause fire and explosion * Keep flammable material away. * Do not weld on containers that

have held combustibles.

PRODUCT DESCRIPTION

The Precision TIG 275 is part of a new family of industrial arc welding power sources providing constant current, single range square wave AC/DC TIG (GTAW) with new patented (pending) Micro-Start Presettable Min. and Max. Output controls, and built-in high frequency stabilization for continuous AC TIG and DC TIG starting. It also has AC/DC Stick (SMAW) capability, with adjustable Arc Force availability. A TIG Pulse Panel. Power Factor Capacitors and a Water Solenoid are available as field installed optional kits. Also, a new Undercarriage (with double gas bottle rack) is available for field installation, as well as a new Under-Cooler Cart, which is also included in an available efficiently integrated entire TIG Welding Package with convenient built-in storage provisions for welding equipment and components.

The Precision TIG 275 includes advanced features such as a Digital Meter, Presettable control, Auto Balance able Postflow shielding gas and Timers. In addition, 2Step/4-Step and Pulse TIG operation with adjustable Downslope Time control are included with an available field installed kit. It also features a Stick stud panel and a universal TIG torch connection box for simultaneous, but separated, electrode outputs.

The Precision TIG 275 has enhanced Features which includes the following:

• MicroStart™ Codes Below 11000

• MicroStart™ II Codes Above 11000

• Auto-Balance optimized

• Menu button added

• Spot On selection added

, Fan As Needed (F.A.N.) fixed Preflow, vari-

Technology,

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

......................................................................................

ARC RAYS can burn. * Wear eye, ear and body protection.

......................................................................................

Observe additional Safety Guidelines detailed in the beginning of this manual.

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PIPE THAWING

The Precision TIG 275 is not recommended for pipe thawing.

Duty Cycle

The duty cycle is based upon a 10-minute time period; i.e., for 40% duty cycle, it is 4 minutes welding and 6 minutes idling. If the rated duty cycle is significantly exceeded, the thermostatic protection will shut off the output until the machine cools to a normal operating temperature. (Refer to Specification Section A-1)

PRECISION TIG 275

B-3

OPERATION

RECOMMENDED PROCESSES AND EQUIPMENT

RECOMMENDED PROCESSES

The Precision TIG 275 is recommended for the TIG (GTAW) and Stick (SMAW) welding processes within its output capacity range of 2 amps DC, or 5 amps AC, to 340 amps AC/DC. It is compatible with most Magnum TIG accessories (refer to Equipment Limitations), as well as many industry standard items, such as TIG torches, hoses, and water coolers.

PROCESS LIMITATIONS Precision TIG machines are not recommended for arc gouging due to it's limited output capacity, and are also not recommended for pipe thawing.

B-3

EQUIPMENT LIMITATIONS

The Precision TIG machines are protected from overloads beyond the electrical ratings and duty cycles, per the Specifications Section A-2, A-3, with Thermostat protection of the primary and secondary transformer coils.

The Precision TIG machines do not have Hi-Freq. available at the Stick electrode stud, therefore stud connection adapters (such as LECO. S19257-series) cannot be used for torch connection.

RECOMMENDED EQUIPMENT/INTERFACE FOR CODES ABOVE 11000

TIG (water cooled) TIG (air cooled) Machine: PT275 Welding Package (K2618-1) PT275(K2619-1,-2) Input Cable/Clamp: User provided User provided Gas Reg./Hose: (included) LE/Harris 3100211 Magnum Torch: (PTW20 included) PTA9 or PTA17 Magnum Parts: (KP510 and K918-2 included) KP507 or KP508 Work Clamp/Lead: (15 ft. included) K2150-1 Work Lead Assembly Foot Amptrol: (K870 included) K870

RECOMMENDED EQUIPMENT/INTERFACE FOR CODES BELOW 11000

TIG (water cooled) TIG (air cooled) Machine: PT275 Welding Package (K1825-1) PT275(K1826-1, -2, K1827-1) Input Cable/Clamp: User provided User provided Gas Reg./Hose: (included) LE/Harris 3100211 Magnum Torch: (PTW20 included) PTA9 or PTA17 Magnum Parts: (KP510 and K918-2 included) KP507 or KP508 Work Clamp/Lead: (15 ft. included) K2150-1 Work Lead Assembly Foot Amptrol: (K870 included) K870 or K870-1

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

PRECISION TIG 275

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

B-4

OPERATION

B-4

CONTROLS AND SETTINGS

The Front Control Panel contains the knobs and switches necessary for adjusting the operation of the Precision TIG 275, with function indicator lights and an electronic display for volts and amps. The components are described below:

FIGURE B.1 - CONTROL PANEL

1. POWER SWITCH

2. POLARITY SWITCH

3. MODE SWITCH

4. AC BALANCE CONTROL

5. LOCAL/REMOTE SWITCH

6. MAXIMUM OUTPUT CONTROL

7. MINIMUM OUTPUT CONTROL AND DISPLAY SWITCH

7.a MENU BUTTON AND DISPLAY

SWITCH FOR CODES ABOVE 11000

DIGITAL METE R AND DISP LAY SWITCH

9. POSTFLOW TIME

10. THERMAL SHUTDOWN LIGHT

11. REMOTE RECEPTACLE

12. TRIGGER SWITCH

13. PULSE MODE SWITCH

14. PULSE FREQUENCY CONTROL

15. PULSE % ON TIME CONTROL

16. PULSE BACKGROUND CURRENT

CONTROL

17. DOWNSLOPE TIME

CURRENT CONTROL

1. POWER SWITCH - Input line switch turns input

power ON or OFF, as indicated by the on or off status of the front panel displays.

2. POLARITY SWITCH – The 3-position rotary power

switch has detente positions for DC-, AC and DC+ selections for the Electrode output welding polarity.

3. MODE SWITCH – The mode switch allows vertical-

ly positioned selection of the two machine welding modes. The selected mode is indicated by a lit colored panel light which permits viewing the machine setting from a distance:

3.a STICK mode (Top position) –Red panel light

WARNING

• The CC Stick mode may be used for general purpose stick welding (SMAW ) within the capacity of the machine. The capacity is too limited for air carbon arc gouging (CAC-A).

• In this mode; the output terminals are activated electrically HOT, gas flow is not activated and HOT START and ARC FORCE levels are fixed, or Advanced Panel selectable (See Section B-7 ), with no front panel adjustment.

3.b TIG mode (Bottom position) – No panel light.

• When the Polarity Switch is set to AC, the TIG

mode provides continuous high frequency to stabilize the arc for AC TIG welding.

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

ELECTRIC SHOCK can kill.

• When the Power Source is ON in STICK mode the Electrode circuits of both the Stick and TIG torch cables are electrically HOT to Work.

------------------------------------------------------------------------

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

• Hi-Freq. turns on after preflow time with the arc start switch closure, and turns off when the arc goes out* after the arc start switch opens.

* Arc voltage and current are sensed to determine if

the arc is established or out.

PRECISION TIG 275

B-5

OPERATION

B-5

• When the Polarity Switch is set to DC (- or +), the TIG mode provides high frequency only for starting.

• Hi-Freq. turns on after pre-flow time with the arc start switch closure, and turns off when the arc is established*

• DC+ polarity can also be used for ”balling” of the tungsten for AC TIG welding.

4. AC BALANCE CONTROL – The potentiometer

control permits AC wave balance adjustment from Max. Penetration (~85% negative wave) with the control at Max. full CW position, to Max. Cleaning (~65% positive wave) with the control set near minimum CCW position.

• Full minimum CCW position is the Auto Balance position which is indicated by the Green panel light turning on. This feature automatically provides the proper amount of cleaning and penetration for normal AC TIG welding

• The mid position is the Balanced position (~50% positive and negative waves).

• With the Current Control switch to REMOTE position, this knob sets the maximum welding level that the Peak output can be set with the remote Amptrol.

• The new MicroStart circuit provides for low end welding (down to 2 amps) previously unobtainable on an SCR platform TIG machine.

7. MINIMUM OUTPUT CONTROL AND DISPLAY SWITCH

A smaller knob is used to preset the minimum current level only for TIG mode. Pressing the Display (momentary) switch toggle left to Minimum Set position displays the Minimum control level setting on the Digital meter. (See Item 8)

• This knob sets the Start output level. When the arc lights (using a new built-in TIG start pulse) this level upslopes quickly (0.5 sec.w/ Advanced Panel, zero w/o) and smoothly to the weld output level. The setting range for this Start control is the 2 amp minimum range of the machine up to about 50 amps, but no more than the level set by the Maximum Output control knob (See Item 6), but otherwise is independent of the Maximum setting.

Technology minimum current

–

• The Balance control is only functional if the machine is set to AC polarity and TIG mode.

5. LOCAL/REMOTE

2-position switch selects how the welding output is controlled for both Stick and TIG Modes:

• LOCAL (Top position) selects output control only by the machine panel Output Control. (See Item 6)

• REMOTE (Bottom position) selects output control to also be by an Amptrol (See Item 6), or other remote (10K pot) control connected to the Remote receptacle (See Item 11) This switch selection is indicated by the Green panel light turning on.

In either position the arc start switch functions when connected to the Remote receptacle (See Item 11).

6. MAXIMUM OUTPUT CONTROL – The large knob

is used to set the output welding current over the rated output range of the machine.

• With the Current Control switch to LOCAL position, this knob sets the welding output level.

CURRENT CONTROL SWITCH

– A

• This setting also serves as the Crater-fill level, but with a Precision TIG Advanced Panel it can be selected (see Section B-7) to be either the Minimum Output control setting (same as Start setting) as shipped, or the minimum rating of the machine (2 amps).

• The Remote Amptrol range of control is between this Minimum setting and the Maximum Output control knob setting, so these knobs can set the resolution of the Amptrol. Also, the Minimum setting serves as both the minimum Amptrol start level when the arc start switch is closed, as well as the minimum Amptrol crater-fill level before the arc start switch is opened to help prevent premature arc out and Hi-Freq re-initiation.

• In STICK mode the Start control is not functional since Hot Start level is fixed, or internal Advanced Panel adjustable (see Section B-7). Pressing the Display (momentary) switch toggle left to Minimum Output position displays minimum amps rating of the machine.

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

PRECISION TIG 275

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

B-6

DIGITAL DISPLAYDIGITAL DISPLAY

(SET)

DISPLAY

(SELECT) DISPLA Y

OPERATION FOR CODES ABOVE 11000 ONLY

B-6

7aaMENU BUTTON AND DISPLAY SWITCH (Codes

above 11000) – Pressing and holding the (Menu)

Button for about 5 seconds

enters

the menu display

which allows:

Selection

•

of up to seven programmable parameters (Preflow, Upslope, Hot Start, Arc Force, etc.) on the digital meter is achieved by momentarily pressing and releasing the MENU button to step through the parameters.

Setting

•

of the desired level, displayed on the digital

meter for the selected parameter, is done by pressing the DISPLAY (momentary) switch toggle to the right to increase the level setting, or to the left to decrease it.

TIG Mode Menu

Setting:

Selection 1:

1 *

Selection 2:

0 1

2 *

3 4 5

Selection 3:

0 *

1 2

∆

Description:

HF (High Freq.)

Scratch start TIG (No Hi-Freq.)

Normal Hi-Freq. start and weld

Lift TIG (Touch start w/o Hi-Freq.)

PF (Preflow time)

No Preflow

0.1 sec.

0.5 sec.

1.0 sec.

1.5 sec.

2.0 sec.

SS (MicroStart™ Start Pulse)

No AC pulse/Low DC pulse (soft start)

High AC/DC pulse (forceful start)

HS setting (see below) for each pulse when Pulse

mode welding anodized aluminum.

* Default Factory Setting. (Indicated by "blinking" decimal point.)

∆

Only selectable with Advanced Control Panel installed.

• Any of the following actions will exit the menu display:

1. Pressing and holding the (Menu) Button again for about 5 seconds.

2. Allowing the menu display to be unchanged for about 15 seconds.

3. Closing the arc start switch (TIG Mode) or starting the arc (Stick Mode). In Stick Mode the machine output will remain on while in menu display.

Note:

TIG Mode Menu (with Advanced Control Panel installed):

Setting:

Selection 4:

0 *

1 2 3 4 5 6 7 8 9

Selection 5:

2 3 4 5

* Default Factory Setting. (Indicated by "blinking" decimal point.)

STICK Mode Menu (with Advanced Control Panel installed ◊ ):

Setting:

Selection 6:

0 1 2 3 4

5 *

6 7 8 9

Selection 7:

1 *

2 3 4 5 6 7 8 9

* Default Factory Setting. (Indicated by "blinking" decimal point.)

◊

If no Advanced Control Panel the Stick menu

displays “- - -“.

Description:

HS (TIG Hot Start % of output setting)

+0% (Only setting for SS0, above.) +10% +20% +30% +40% +50% +60% +70% +80% +90% UP (Upslope Time) None (Only setting for SS1 & SS2, above.)

0.5 sec.

1.0 sec.

1.5 sec.

2.0 sec.

2.5 sec.

Description: HS (Stick Hot Start % added to output setting)

+0% +10% +20% +30% +40% +50% +60% +70% +80% +90% AF (Stick Arc Force % added to output setting) +0% ("Softer" arc) +10% +20% +30% +40% +50% +60% +70% +80% +90% ("Crisper" arc)

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

• Re-entering the menu displays the last parameter and setting that was displayed when the menu was exited.

• All settings may be reset to the Factory Default Settings (above) by holding the (Menu) button pressed while

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

turning on the machineʼs Power switch. The display will show “rES” to indicate the defaults are reset.

PRECISION TIG 275

B-7

Max

10K ohm

Min

REMOTE RECEPTACLE*

(Front View)

REMOTE OUTPUT

CONTROL

ARC START

SWITCH

*For 18-12P Plug

(LECO S12020-27)

OPERATION

B-7

8. DIGITAL METER AND DISPLAY SWITCH– A 3-

digit LED meter is used to monitor the preset and actual welding procedure based on the Display (momentary) switch position:

• Before welding with Display switch in center (normal) position, the digital meter displays the preset welding amps set by Maximum Output control knob (See Item 6). If in Stick mode using REMOTE (See Item 5.), the digital meter displays the preset welding amps set by the Remote control. (See Item 11)

• While welding with Display switch in center (normal) position, the digital meter displays the actual welding amps with one amp resolution (XXX) and accuracy within 4%+/-2A of reading.

• At any time in TIG mode, pressing the Display switch to left causes the digital meter displays the amps preset by the Minimum Output control knob (See Item 7).

• At any time in Stick mode, pressing the Display switch to left causes the digital meter to display the minimum amps rating of the machine (See Item 7).

• In either mode, while pressing the Display switch

right to Volts position, the digital meter displays actual output volts. Volts is displayed with 0.1 volt resolution (XX.X) and accuracy within 3%+/-1V of reading.

• When the Current Control Switch is in either or REMOTE

positions the arc start switch functions

LOCAL

when connected to the Remote receptacle.

FIGURE B.2

ADVANCED PANEL CONTROLS

The following controls are included only if the Precision TIG 275 has the Advanced Control Panel (K1829-1)

option installed: (Refer to Figure B.3 Tig Weld Cycle

Chart for graphic illustration of these TIG welding functions.)

12. TRIGGER SWITCH – This 2-position switch

selects how the arc start switch ( connected to the above Remote receptacle) functions; in 2-Step or 4-Step mode:

9. POSTFLOW TIME – This knob is used to set the

TIG mode shielding gas postflow time over the range of about 2 to 60 seconds after the arc is shut off. The postflow on time status is indicated by the Green panel light.

• Gas preflow time for TIG mode is fixed at 0.5 seconds, with no panel control.

• Both time ranges are x2 extendable, if needed, by internal control box selection. (See Section B-7)

10. THERMAL SHUTDOWN LIGHT– This yellow LED

panel light turns on if the machine output is shutdown because internal overheating has occurred, and turns off when the thermostat resets.

11. REMOTE RECEPTACLE – A 6-socket receptacle

is provided for the connection of an Amptrol, or other remote control: (See Figure B.2)

• When the Current Control Switch (See Item 5) is in

the REMOTE position, the Amptrol or other remote (10K pot) connected to the Remote receptacle controls the TIG or Stick mode output within the range preset by the Maximum and Minimum Output controls. (See Item 6, 7, and 8 for meter display.)

CAUTION

• DO NOT USE 4-STEP IF USING AN AMPTROL REMOTE.

• Neither the arc start switch nor the output control in the amptrol will function normally to shut off or control the output. ONLY USE 2-STEP.

------------------------------------------------------------------------

• In 2-Step position the arc start switch functions the same as without the Advanced Panel:

1. Closing switch starts preflow, then a fixed (0.5 sec.) ramp time from Minimum (Start) setting level (See Item 7) to Weld setting.

2. Opening switch initiates Downslope ramp time setting (See Item 17), from Weld setting to Crater-fill level (See Item 7), which then stops the arc and initiates Postflow time (See Item 9).

Note: See Figure B.3 for 2-Step operation during

Downslope with Restart feature selected to be disabled, instead of enabled (as shipped).

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

PRECISION TIG 275

B-8

OPERATION

B-8

• The 4-Step position allows welding without continuously holding the start switch trigger. The arc start switch functions in the following manner:

1. Closing the switch starts preflow, then arc starts at Minimum (Start) setting level (See Item 7). If the trigger is maintained closed after preflow time the output remains at the Start level until it is released.

2. Opening the switch initiates fixed (0.5 sec.) ramp time from Start setting level to Weld setting.

3. Reclosing the switch initiates Downslope ramp time setting (See item 17) from Weld setting down to the Crater-fill level (See Item 7) of the machine.

4. Reopening the switch after Downslope time holds Crater-fill level until it times out, then stops the arc and initiates the Postflow Time (See Item 9). Reopening switch during Downslope time immediately stops the arc and initiates the Postflow.

Note: See Figure B.4 for 4-Step operation during

Downslope with Restart feature selected to be enabled, instead of disabled (as shipped).

13.PULSE MODE SWITCH (PULSE / SPOT MODE SWITCH for codes above 11000) – Turns on the

Pulse Mode as indicated by the Green panel light turning on.

• PULSE ON position provides a Peak current level

set by REMOTE and/or LOCAL control of the output current (See Item5), for a time determined by the Pulse Frequency Control setting (See Item 14) and the % ON Time (See Item 15). The balance of the cycle time is at the Background Current level (See Item 16).

14. PULSE FREQUENCY CONTROL – This knob is

used to set the Pulse Frequency over the peak pulse range of about 0.1 pps to 20 pps. (One pulse cycle time = 1/pps = 10 to .05 sec. range.)

15. PULSE % ON TIME CONTROL (PULSE% ON /

SPOT TIME CONTROL for codes above 11000) •

• % ON TIME controls the duration of the peak cur-

rent as a percentage (5% to 95%) of one pulse cycle. The balance of the cycle time will be at the Background Current setting. (See Item 16)

• SPOT TIME sets the duration of the SPOT pulse

(0.5 to 5.0seconds on the red scale).

16. PULSE BACKGROUND CURRENT CONTROL –

This knob controls the level of the Background Current as a percentage (MIN.-100%) of the Peak (REMOTE and/or LOCAL) output level (See Item

6) down to the Minimum Output setting (See Item

7).

17. DOWNSLOPE TIME– This knob is used to set the

time, over the range of zero to about 10 seconds, to ramp down from weld setting to Crater-fill level (See Item 7).

• If the arc goes out after the Downslope time is initiated, the Downslope time is interrupted and the Postflow time is initiated. This prevents Hi-Freq reinitiation during ramp down crater fill

• When using an Amptrol remote control, where the downslope is controlled by the operator down to the crater-fill level, the Downslope time should be set to zero so as not to have the Downslope time delay when the arc start switch is opened.

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

• Pulsing begins after upslope when the output current rises above the Background Current level and ends when the output current drops below this level .

• SPOT ON position provides the peak current level set by the Maximum Output Control for a time determined by the SPOT TIME control. A red panel light is ON to indicate SPOT mode.

PRECISION TIG 275

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

B-9

HOT START

ARC FORCE

^ ON

1 2 3 4 5 6 7

DIP SWITCH (S1)

S F

OPERATION

INTERNAL SET UP CONTROLS

Precision TIG 275 models which have an Advanced Panel (K1829-1) option installed* have the following additional control features which are set up using the DIP Switch (S1) provided on the internal panel of this option.

B-9

• Switch #7 Arc Force Level(codes below 11000)–

Prevents "stubbing" of the electrode by providing extra output current if the arc voltage drops below the level required to sustain the welding arc. High (+65%) and Low (+12%) factory set levels are selectable which are good for most stick welding applications.

Access to this internal panel is obtained by removing the two screws securing the top corners of the Precision TIG front control panel and swinging the control panel down to reveal the panel mounted on the surface of the Precision TIG Control board:

CAUTION

• THE CONTROL BOARDS CONTAIN STATIC SENSITIVE COMPONENTS

• To avoid possible damage to these components be sure to ground yourself by touching the machineʼs sheet metal while handling or making settings on the internal control box components.

------------------------------------------------------------------------

PRECISION TIG ADVANCED PANEL

(Internal Panel)

ON – Higher for a "crisper" arc, often desired for 6010

type electrodes.

OFF – Lower Arc Force (as shipped) for a "softer" arc

with 7018 or general type electrodes.

• Switch #6 & #7 - Not functional on codes above 11000 - See item 7a for adjustment of Hot Start and Arc Force

• Switch #8 - (NOT CURRENTLY FUNCTIONAL)

TIG WELDING FEATURES

The following DIP switch feature selections function only when the Precision TIG is set to TIG mode (See Item 3):

• Switch #1 Preflow/Postflow Time Extension*

(See Item 9)

ON – Doubles the time ranges. OFF – Standard time ranges (as shipped).

12 3 456 7 8

OFF

DIP SWITCH POSITIONS (FACTORY SETTINGS)

STICK WELDING FEATURES

The following DIP switch feature selections function only when the Precision TIG is set to Stick mode. (See Item 3):

• Switch #6 Hot Start Level (codes below 11000) –

Provides an extra output "boost" pulse at the arc strike to enhance arc starting. This is factory set for a level (about 50% extra) which is usually good for most stick welding applications

ON – Hot Start level is used (as shipped). OFF – No Hot Start.

• Switch #2 2-Step Trigger Restart Feature (See

Figure B.3)

ON – Restart Enabled (as shipped). OFF – Restart Disabled.

• Switch #3 4-Step Trigger Restart Feature (See

Figure B.4)

ON – Restart Enabled. OFF – Restart Disabled (as shipped)

• Switch #4 (NOT CURRENTLY FUNCTIONAL)

• Switch #5 Crater-Fill Level (See Item 7)

ON - Level is minimum rating of the machine (2A) OFF – Level (as shipped) is Minimum Output setting

(same as Start level).

The Preflow/Postflow Time doubling feature can also be selected

on Precision TIG 275 models without the Advanced Panel by accessing the Control board in the control box per above instructions, then disconnecting the jumper terminals attached to the jumper plug connected to receptacle J3 of the Control board. (Refer to Machine Wiring Diagram.)

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

B-10

2 Step Trigger Modes

2 Step - Restart Disabled

2 Step - Restart Enabled

Torch Button

Output Current

Gas

Pre-Flow

Post Flow

Normal Sequence

orch

Button

utput

Current

Gas

Pre-Flow

Post Flow

START/CRATER CURRENT

UP-SLOPE

OWN-SLOPE

(With DIP Switch #2 OFF)

(With DIP Switch #2 ON. As Shipped)

Actuate the trigger a second t

ime, during down-slope, to immediately end down-slope. Hold the trigger to maintain crater current.

Torch Button

Output Current

Gas

Pre-Flow

Post Flow

Actuate the trigger a second time, during down-slope, to activate up-slope and restart.

2 Step.eps 12-17-07 JRH

OPERATION

FIGURE B.3

B-10

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

B-11

4 Step Trigger Modes

4 Step - Restart Enabled

4 Step - Restart Disabled

Torch Button

Output C

urrent

Gas

Pre-Flow Pre-Flow

Post Flow

ost Flow

Normal Sequence

Torch Button

Output Current

Gas

Pre-Flow

Post Flow

START/CRATER CURRENT

UP-SLOPE

DOWN-SLOPE

(With DIP Switch #3 ON)

(With DIP Switch #3 OFF. As Shipped)

Post Flow

old the second trigger pull for more than 1 second to activate the restart function. When the trigger is released up-slope will occur.

ctuate the trigger holding it less than 1 second, to begin normal down-slope. The following two options are available during the normal down-slope period.

ctuate the trigger again, during down-slope, to immediately end down-slope and stop.

r actuate and hold the trigger, during down-slope, to immediately end down-slope and maintain crater current. Hold the trigger for more than 1 second to activate the restart function. When the trigger is released up-slope will occur.

Hold the first trigger pull to maintain the starting current and delay u

p-slope.

Torch Button

Output Current

Gas

4 Step.eps 12-17-07 JRH

Pre-Flow

Post Flow

Post Flow Post Flow

Hold the second trigger pull for more than 1 second to maintain crater current before stopping.

Actuate the trigger holding it less than 1 second, to begin normal down-slope. The following two options are available during the normal down-slope period.

Actuate the trigger a third time, during down-slope, to immediately end down-slope and stop.

Or actuate the trigger a third time, during down-slope, to immediately end down-slope. Hold the third trigger pull to maintain crater current.

OPERATION

FIGURE B.4

B-11

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

B-12

PREFLOW

ixed 0.5 sec

or x2

TART TIME

Manual

in 4-Step

UPSLOPE

ixed<0.5 sec

w/o Amptrol

MINIMUM OUTPUT

(

Start) SETTING

Adjustable 2-50A

MAXIMUM OUTPUT

ETTING

Adjustable 2-Max.A

Amptrol or Remote

(PEAK) Range

2 or 4-STEP

Trigger

Closed

4-STEP Trigger

1ST Open

4-STEP Trigger

Re-closed or

2-STEP Trigger

pened

4-STEP Trigger

Re-opened

after

ownslope Time

DOWNSLOPE

djust 0 –10 sec

w/ Advan. Panel

(

Fixed 0 sec w/o)

POSTFLOW

Adjust 2-60 sec

or x2

CRATER-FILL

EVEL

dvanced

Panel Select:

Mach. Min.

MIN. Setting

(as w/o Panel)

With PULSE ON

o Pulsing

During Upslope Time

hen Downslope

Drops Below

ackground Setting

ON TIME

Adjustable

5-95%

ULSE FREQ.

Adjustable

0.1-20 pps

BACKGROUND

Adjustable

MIN.Setting -100% Peak

CRATER-FILL TIME

Manual in 2/4-Step

w/ Restart Disabled



TIG WELD CYCLE CHART

OPERATION

CCOODDEESS BBEELLOOWW 1111000000 ((KK11882299--11))

B-12

CCOODDEESS AABBOOVVEE 1111000000 ((KK22662211--11))

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

PRECISION TIG 275

B-13

Max. to Min.

Amptrol

Min. to Max.

Amptrol

Setup for TIG Amptrol Welding

Advanced Panel

(If used)

Standard Controls

Power Switch

olarity Switch

AC or DC-

Mode Switch

TIG

AC Balance

AUTO

Set:

More + for alum. oxide “Cleaning“

w/o “spitting”or“wetting“ loss.

alanced for equal

and

current.

More - for higher “Penetration“.

Local/Remote

Switch

REMOTE

Trigger Switch

2-STEP

Pulse Switch

ON or OFF

Pulse Frequency

4-6 pps is a typical initial setting.

Set for bead shape and travel speed: Higher for thinner plate and faster travel. Lower for thicker plate and slower travel.

% On Time

40-60% is a typical initial setting.

Set for total heat of Peak current:

Lower reduces distortion and burn-thru.

Background Current

40-60% is a typical initial setting.

Set as low as will maintain a pulse arc

(Will not drop below

Min.Output

setting.)

Downslope

ZERO

For no arc-out delay.

Minimum Output

Press Display switch

and Set to desired min.

mptrol (Start/Crater)

utput level.

Postflow

Set as low as required.

Higher for larger

ungsten and current.

Maximum Output

et to desired max.

mptrol output level.

OPERATION

FIGURE B.6

B-13

SETUP GUIDELINES FOR TIG WELDING WITH AN AMPTROL

Both the Hand and Foot Amptrols work in a similar manner. They are meant to be used for remote current control for TIG welding using the machineʼs 2-Step trigger mode (See Item 12).

The Amptrol is capable of controlling the output of the Precision TIG over the range between the level preset by the Minimum Output control when the Amptrol is at its inactivated state, and the level preset by the Maximum Output control when the Amptrol is at fullyactivated state.

AA ddvvaanncceedd PPaanneell

Controls

It is important to note that even with the Precision TIGʼs new MicroStartTMTechnology, some tungsten may be difficult to start at the low (2 amps) minimum rating of the machine. Rather than guessing where to depress the Amptrol to start the arc reliably, the Minimum Output control allows presetting the exact level, so reliable starts, as well as minimum crater-fill levels, can be consistently obtained at the minimum Amptrol (inactivated ) state. FIGURE B.6 shows Precision TIG setup for TIG welding with an Amptrol.

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

PRECISION TIG 275

B-14

OPERATION

B-14

MAKING A TIG WELD WITH AN AMPTROL

1. Install welding equipment per Section A-5.

2. Setup controls per Section B-9.

3. Turn on the shielding gas supply, and torch coolant input supply (if used).

Note: The Precision TIG Under-Cooler (or Water Solenoid connected to the Cooler receptacle) runs with the Fan-As-Needed machine cooling fan (See Maintenance Section D), so the cooler fan and water pump will also not run continuously in idle, but will run while welding.

4. With the torch held safely away from everything, close the Arc Start Switch of the Amptrol and set the gas flow meter. Then open the switch. The welder is now ready for welding.

5. Position the tungsten electrode at the start of the weld at a 65° to 75° angle with the horizontal, in the direction of pushing travel, so that the electrode is approximately 1/8" (4 mm) above the work piece.

RECOMMENDED ELECTRODE AMPERAGE RANGES - PRECISION TIG 275

Close the arc start switch. This opens the gas valve to automatically purge air from the hose and torch, then shields the arc strike area. After the 0.5 second preflow time, the high frequency becomes available to strike the arc. When the arc strikes the torch coolant (if used) starts to flow. Also, if welding DC- TIG, the high frequency shuts off just after the arc strikes.

6. Hold the arc start switch closed at minimum Amptrol Start level (See Section B-10) until an arc is established, then increase the output to the desired welding level and push the torch in the direction of travel.

7. At the end of the weld, decrease the Amptrol output to the crater-fill level before releasing the arc start switch to start the Postflow time. Hold the torch gas shielding over the solidifying weld crater while postflow time expires and the gas valve reopens. The torch coolant (if used) continues to flow for up to 8 minutes after the arc goes out (with the Fan-AsNeeded feature) to assure torch cooling.

• Repeat steps 5 through 7 to make another weld.

Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC

SMAW Process

ELECTRODE POLARITY 3/32" 1/8" 5/32" Fleetweld 5P, Fleetweld 5P+ DC+ 40 - 70 75 - 130 90 - 175 Fleetweld 180 DC+ 40 - 80 55 - 110 105 - 135 Fleetweld 37 DC+ 70 - 95 100 - 135 145 - 180 Fleetweld 47 DC- 75 - 95 100 - 145 135 - 200 Jet-LH MR DC+ 85 - 110 110 - 160 130 - 220 Blue Max Stainless DC+ 40 - 80 75 - 110 95 - 110 Red Baron Stainless DC+ 40 - 70 60 - 100 90 - 140

Mild steel procedures are based on recommended procedures listed in C2.10 8/94 and the maximum rating of the PRECISION TIG 275 Excaliber 7018 procedures are based on Jet-LH 78 MR Blue Max procedures are based on C6.1 6/95 Red Baron Procedure are based on ES-503 10/93

GTAW Process

Electrode Polarity DC- AC* Approximate Argon

Electrode Tip Preparation Sharpened Balled Gas Flow Rate

Electrode Type

EWTh-1, EWCe-2 EWTh-1, EWTh-2

EWZr C.F.H. (l/min.)

EWTh-2, EWLa-1 EWP EWCe-2, EWLa-1 Stainless

Electrode Size (in.) EWG EWG Aluminum Steel

.010 Up to 15 A. Up to 15 A. Up to 15 A. 3-8 (2-4) 3-8 (2-4) .020 Up to 15 A. 10 to 15 A. 5 to 20 A. 5-10 (3-5) 5-10 (3-5) .040 Up to 80 A. 20 to 30 A. 20 to 60 A. 5-10 (3-5) 5-10 (3-5) 1/16 Up to 150 A. 30 to 80 A. 60 to 120 A. 5-10 (3-5) 9-13 (4-6) 3/32 Up to MAX. A. 60 to 130 A. 100 to 180 A. 13-17 (6-8) 11-15 (5-7)

1/8 X 100 to 180 A. 160 to 250 A. 15-23 (7-11) 11-15 (5-7)

Tungsten electrodes are classified as follows by the American Welding Society (AWS):

Pure .........................................EWP...........green

+1% Thoria ..............................EWTh-1......yellow

+2% Thoria ..............................EWTh-2......red

+2% Ceria................................EWCe-2 .....orange

+1.5% Lanthana ......................EWLa-1......black

+0.15 to 0.40% Zirconia ..........EWZr..........brown

Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC

Ceriated Tungsten is now widely accepted as a substitute for 2% Thoriated Tungsten in AC and DC applications.

Balanced Wave, Unbalanced Wave requires derating of the electrode.

PRECISION TIG 275

+ 110 hidden pages