INSTRUCTIONS for

MIGMASTER 250

WELDING PACKAGES

F-15-087-E

August, 1997

NOTE: This manual is also suitable for use with L-TEC Migmaster 250 package.

These INSTRUCTIONS are for experienced operators. If you are not fully familiar with the principles of operation and safe practices for electric welding equipment, we urge you to read our booklet,

"Precautions and Safe Practices for Arc Welding, Cutting and Gouging." Form 52-529. Do NOT permit untrained persons to install, operate, or maintain this equipment. Do NOT attempt to install or operate this equipment until you have read and fully understand these Instructions. If you do not fully understand these Instructions, contact your supplier for further information. Be sure to read the

Safety Precautions on page 2 before installing or operating this equipment.

Be sure this information reaches the operator.

You can get extra copies through your supplier.

USER RESPONSIBILITY

This equipment will perform in conformity with the description thereof contained in this manual and accompanying labels and/or inserts when installed, operated, maintained and repaired in accordance with the instructions provided.

This equipment must be checked periodically. Defective equipment should not be used. Parts that are broken, missing, worn, distorted or contaminated should be replaced immediately. Should such repair or replacement become necessary, the manufacturer recommends that a telephone or written request for service advice be made to the

Authorized Distributor from whom purchased.

This equipment or any of its parts should not be altered without the prior written approval of the manufacturer. The user of this equipment shall have the sole responsibility for any malfunction which results from improper use, faulty maintenance, damage, improper repair or alteration by anyone other than the manufacturer or a service facility designated by the manufacturer.

2

TABLE OF CONTENTS

SECTION NO.

PAGE NO.

SECTION 1 - GENERAL SAFETY RULES FOR WELDING

AND CUTTING ........................................................................................................... 4

GENERAL PRECAUTIONS .................................................................................................. 4

PRECAUTION SYMBOL DEFINITIONS ........................................................................ 5

SECTION II - INTRODUCTION ............................................................................................. 6

2.1

GENERAL .................................................................................................................. 6

2.2

RECEIVING-HANDLING ............................................................................................ 6

2.3

DESCRIPTION, Available Packages/Contents ........................................................... 6

2.4

OPTIONAL ACCESSORIES ....................................................................................... 7

2.5

SAFETY ..................................................................................................................... 9

SECTION III - INSTALLATION ............................................................................................. 9

3.1

LOCATION ................................................................................................................. 9

3.2

ELECTRICAL INPUT CONNECTIONS ...................................................................... 9

3.3

SECONDARY OUTPUT CONNECTIONS ................................................................ 12

3.4

TORCH CONNECTIONS ......................................................................................... 12

3.5

WIRE FEEDER MECHANISM .................................................................................. 12

3.6

CONNECTION OF THE SHIELD GAS ..................................................................... 13

3.7

WELDING CABLE CONNECTIONS ......................................................................... 14

3.8

ASSEMBLE REAR WHEELS ................................................................................... 14

3.9

INSTALLING OPTIONAL SPOT/STITCH/ANTI-STICK MODULE ............................ 14

3.10

INSTALLING OPTIONAL DIGITAL METER ............................................................. 14

SECTION IV - OPERATION ................................................................................................ 15

4.1

CONTROLS .............................................................................................................. 15

4.2

PROCESS SETUP ................................................................................................... 16

4.3

OPERATING PROCEDURES .................................................................................. 19

SECTION V - SERVICE ...................................................................................................... 22

5.1

MAINTENANCE ....................................................................................................... 22

5.2

INSPECTION AND SERVICE .................................................................................. 22

5.3

TROUBLESHOOTING .............................................................................................. 23

SECTION VI - PARTS ......................................................................................................... 26

6.1

SPARE PARTS ........................................................................................................ 26

6.2

REPLACEMENT PARTS .......................................................................................... 26

6.3

ORDERING .............................................................................................................. 26

3

SAFETY PRECAUTIONS

tional Safety Information section. Before performing any installation or operating procedures, be sure to read and follow the safety precautions listed below as well as all other manuals, material safety data sheets, labels, etc.

Failure to observe Safety Precautions can result in injury or death.

WARNING:

T hese Safety Precautions are for your protection. They summarize precautionary information from the references listed in Addi-

PROTECT YOURSELF AND OTHERS

--

Some welding, cutting, and gouging processes are noisy and require ear protection. The arc, like the sun, emits ultraviolet (UV) and other radiation and can injure skin and eyes. Hot metal can cause burns.

Training in the proper use of the processes and equipment is essential to prevent accidents. Therefore:

1. Always wear safety glasses with side shields in any work area, even if welding helmets, face shields, and goggles are also required.

2. Use a face shield fitted with the correct filter and cover plates to protect your eyes, face, neck, and ears from sparks and rays of the arc when operating or observing operations. Warn bystanders not to watch the arc and not to expose themselves to the rays of the electric-arc or hot metal.

3. Wear flameproof gauntlet type gloves, heavy long-sleeve shirt, cuffless trousers, high-topped shoes, and a welding helmet or cap for hair protection, to protect against arc rays and hot sparks or hot metal. A flameproof apron may also be desirable as protection against radiated heat and sparks.

4. Hot sparks or metal can lodge in rolled up sleeves, trouser cuffs, or pockets. Sleeves and collars should be kept buttoned, and open pockets eliminated from the front of clothing

5. Protect other personnel from arc rays and hot sparks with a suitable non-flammable partition or curtains.

6. Use goggles over safety glasses when chipping slag or grinding. Chipped slag may be hot and can fly far.

Bystanders should also wear goggles over safety glasses.

FIRES AND EXPLOSIONS -- Heat from

flames and arcs can start fires. Hot slag or sparks can also cause fires and explosions. Therefore:

1. Remove all combustible materials well away from the work area or cover the materials with a protective nonflammable covering. Combustible materials include wood, cloth, sawdust, liquid and gas fuels, solvents, paints and coatings, paper, etc.

2. Hot sparks or hot metal can fall through cracks or crevices in floors or wall openings and cause a hidden smoldering fire or fires on the floor below. Make certain that such openings are protected from hot sparks and metal.“

3. Do not weld, cut or perform other hot work until the workpiece has been completely cleaned so that there are no substances on the workpiece which might produce flammable or toxic vapors. Do not do hot work on closed containers. They may explode.

4. Have fire extinguishing equipment handy for instant use, such as a garden hose, water pail, sand bucket, or portable fire extinguisher. Be sure you are trained in its use.

5. Do not use equipment beyond its ratings. For example, overloaded welding cable can overheat and create a fire hazard.

6. After completing operations, inspect the work area to make certain there are no hot sparks or hot metal which could cause a later fire. Use fire watchers when necessary.

7. For additional information, refer to NFPA Standard 51B,

"Fire Prevention in Use of Cutting and Welding Processes", available from the National Fire Protection Association,

Batterymarch Park, Quincy, MA 02269.

ELECTRICAL SHOCK -- Contact with live electrical parts and ground can cause severe injury or death. DO NOT use AC welding current in damp areas, if movement is confined, or if there is danger of falling.

1. Be sure the power source frame (chassis) is connected to the ground system of the input power.

2. Connect the workpiece to a good electrical ground.

3. Connect the work cable to the workpiece. A poor or missing connection can expose you or others to a fatal shock.

4. Use well-maintained equipment. Replace worn or damaged cables.

5. Keep everything dry, including clothing, work area, cables, torch/electrode holder, and power source.

6. Make sure that all parts of your body are insulated from work and from ground.

7. Do not stand directly on metal or the earth while working in tight quarters or a damp area; stand on dry boards or an insulating platform and wear rubber-soled shoes.

8. Put on dry, hole-free gloves before turning on the power.

9. Turn off the power before removing your gloves.

10. Refer to ANSI/ASC Standard Z49.1 (listed on next page) for specific grounding recommendations. Do not mistake the work lead for a ground cable.

ELECTRIC AND MAGNETIC FIELDS — May be dangerous. Electric current flowing through any conductor causes localized

Electric and Magnetic Fields (EMF). Welding and cutting current creates EMF around welding cables and welding machines.

Therefore:

1. Welders having pacemakers should consult their physician before welding. EMF may interfere with some pacemakers.

2. Exposure to EMF may have other health effects which are unknown.

3. Welders should use the following procedures to minimize exposure to EMF:

A. Route the electrode and work cables together. Secure them with tape when possible.

B. Never coil the torch or work cable around your body.

C. Do not place your body between the torch and work cables. Route cables on the same side of your body.

D. Connect the work cable to the workpiece as close as possible to the area being welded.

E. Keep welding power source and cables as far away from your body as possible.

4

11/95

FUMES AND GASES -- Fumes and gases, can cause discomfort or harm, particularly in confined spaces. Do not breathe fumes and gases. Shielding gases can cause asphyxiation.

Therefore:

1. Always provide adequate ventilation in the work area by natural or mechanical means. Do not weld, cut, or gouge on materials such as galvanized steel, stainless steel, copper, zinc, lead, beryllium, or cadmium unless positive mechanical ventilation is provided. Do not breathe fumes from these materials.

2. Do not operate near degreasing and spraying operations.

The heat or arc rays can react with chlorinated hydrocarbon vapors to form phosgene, a highly toxic gas, and other irritant gases.

3. If you develop momentary eye, nose, or throat irritation while operating, this is an indication that ventilation is not adequate. Stop work and take necessary steps to improve ventilation in the work area. Do not continue to operate if physical discomfort persists.

4. Refer to ANSI/ASC Standard Z49.1 (see listing below) for specific ventilation recommendations.

CYLINDER HANDLING -- Cylinders, if mishandled, can rupture and violently release gas. Sudden rupture of cylinder, valve, or relief device can injure or kill. Therefore:

1. Use the proper gas for the process and use the proper pressure reducing regulator designed to operate from the compressed gas cylinder. Do not use adaptors. Maintain hoses and fittings in good condition. Follow manufacturer's operating instructions for mounting regulator to a compressed gas cylinder.

2. Always secure cylinders in an upright position by chain or strap to suitable hand trucks, undercarriages, benches, walls, post, or racks. Never secure cylinders to work tables or fixtures where they may become part of an electrical circuit.

3. When not in use, keep cylinder valves closed. Have valve protection cap in place if regulator is not connected.

Secure and move cylinders by using suitable hand trucks.

Avoid rough handling of cylinders.

4. Locate cylinders away from heat, sparks, and flames.

Never strike an arc on a cylinder.

5. For additional information, refer to CGA Standard P-1,

"Precautions for Safe Handling of Compressed Gases in

Cylinders", which is available from Compressed Gas

Association, 1235 Jefferson Davis Highway, Arlington,

VA 22202.

EQUIPMENT MAINTENANCE -- Faulty or improperly maintained equipment can cause injury or death. Therefore:

1. Always have qualified personnel perform the installation, troubleshooting, and maintenance work. Do not perform any electrical work unless you are qualified to perform such work.

2. Before performing any maintenance work inside a power source, disconnect the power source from the incoming electrical power.

3. Maintain cables, grounding wire, connections, power cord, and power supply in safe working order. Do not operate any equipment in faulty condition.

4. Do not abuse any equipment or accessories. Keep equipment away from heat sources such as furnaces, wet conditions such as water puddles, oil or grease, corrosive atmospheres and inclement weather.

5. Keep all safety devices and cabinet covers in position and in good repair.

6. Use equipment only for its intended purpose. Do not modify it in any manner.

ADDITIONAL SAFETY INFORMATION -- For more information on safe practices for electric arc welding and cutting equipment, ask your supplier for a copy of "Precautions and Safe Practices for

Arc Welding, Cutting and Gouging", Form

52-529.

The following publications, which are available from the

American Welding Society, 550 N.W. LeJuene Road, Miami,

FL 33126, are recommended to you:

1. ANSI/ASC Z49.1 - "Safety in Welding and Cutting"

2. AWS C5.1 - "Recommended Practices for Plasma Arc

Welding"

3. AWS C5.2 - "Recommended Practices for Plasma Arc

Cutting"

4. AWS C5.3 - "Recommended Practices for Air Carbon Arc

Gouging and Cutting"

5. AWS C5.5 - "Recommended Practices for Gas Tungsten

Arc Welding“

6. AWS C5.6 - "Recommended Practices for Gas Metal Arc

Welding"“

7. AWS SP - "Safe Practices" - Reprint, Welding Handbook.

8. ANSI/AWS F4.1, "Recommended Safe Practices for Welding and Cutting of Containers That Have Held Hazardous

Substances."

This symbol appearing throughout this manual means Atten-

tion! Be Alert! Your safety is involved.

The following definitions apply to DANGER,

WARNING, CAUTION found throughout this manual:

Used to call attention to immediate hazards which, if not avoided, will result in immediate, serious personal injury or loss of life.

Used to call attention to potential hazards which could result in personal injury or loss of life.

Used to call attention to hazards which could result in minor personal injury.

5

II. INTRODUCTION

2.1 GENERAL

This manual has been prepared especially for use in familiarizing personnel with the design, installation, operation, maintenance, and troubleshooting of this equipment. All information presented here in should be given careful consideration to assure optimum performance of this equipment.

2.2 RECEIVING-HANDLING

Prior to installing this equipment, clean all packing material from around the unit and carefully inspect for any damage that may have occurred during shipment. Any claims for loss or damage that may have occurred in transit must be filed by the purchaser with the carrier. A copy of the bill of lading and freight bill will be furnished by the carrier on request if occasion to file claim arises.

When requesting information concerning this equipment, it is essential that Part, Serial and Model Numbers of the equipment be supplied.

2.3 DESCRIPTION

The Migmaster 250 is a portable Welding System designed for fine wire, (0.023, 0.030, 0.035 and 0.045 in.) welding using the short arc method, as well as for spray arc aluminum, short arc and spray arc stainless steel and spray arc cored wires. It incorporates a running gear with provisions for one gas cylinder, and a ST-23A spool-ongun control.

2.3.1 AVAILABLE PACKAGES AND CONTENTS

The following Migmaster 250 “Consisting of” Packages are available:

MM-250 for 208/230-V. Input w/12-ft. Kit . P/N 604560

MM-250 for 208/230-V. Input w/15-ft. Kit . P/N 604561

MM-250 for 208/230/380/400/460/575-V. Input w/12-ft. Kit

.............................................................. P/N 604563

MM-250 for 208/230/380/400/460/575-V. Input w/15-ft. Kit

.............................................................. P/N 604570

Depending on the “primary input voltage” of the MM-250, and the “torch length”, each package includes the following: l

One (1), Migmaster 250 Power Supply/Wire Feeder equipped with a dual-groove feed roll (for .035/.045 wire), a 6'-0" ft. primary input power cable and plug (plug is installed for 208/230-V. units only), an input power receptacle rated @ 50A./250-V. (packed loose for 208/230-V.

input packages only), 10-ft. work cable w/clamp, a 6'-0" shielding gas supply hose w/fittings and running gear w/ gas (cylinder) support, as follows:

-- Migmaster 250 for 208/230-Volt input .... P/N 32851

-- Migmaster 250 for 208/230/380/400/460/575-Volt input ....................................................... P/N 32852 l

One (1), Migmaster 250 Kit as follows:

-- 12-ft. Kit ................................................. P/N 32993

Includes:

MT-200cc, ready-to-weld, 12-ft. lg. torch for .035/.045 wire ....................................... P/N 21116

R-33-FM-580 Regulator, (F-15-173) ........... P/N 21557

Mig Welding Process Handbook .............. P/N 791F18

-- 15-ft. Kit ................................................. P/N 32994

Includes same accessories as 12-ft. Kit except for torch, which is:

MT-200cc, 15-ft. lg. for .035/.045 wire, ....... P/N 21117

2.3.2 POWER SUPPLY

The power supply consists of a tapped single phase transformer, tap selection switches, secondary contactor, single phase full wave rectifier, stabilizing reactor, slope resistor, filtering capacitors and internal output connections for polarity reversal.

2.3.3 WIRE FEEDER

The wire feeder pushes 0.023, 0.030, 0.035 and 0.045 in.

wire at speeds up to 650 IPM. Dynamic braking prevents excessive wire overrun. A double grooved drive roll

(0.035 and 0.045 in.) provides a convenient means of changing the setup for either wire size.

The wire feeder is built into the power supply cabinet, and is housed in a compartment separated from the welding machine components. Machine ventilation is not drawn through this compartment, thus helping to keep the wire and feeding mechanism clean.

6

POWER SOURCE

Rated Output

Duty Cycle, 208/230V Unit

208/230/380/400/460/575V Unit

Primary Input

Primary Input Amperes

Output Current Range

Maximum Open Circuit Volts

FEEDER

Feed Type

Wire Sizes Hard & Cored

Feed Rate

MT-200cc TORCH

Cooling

Gooseneck Angle

Rated 60% Duty Cycle

(DCRP) Amps:

Conduit Length

PHYSICAL

Net Weight

Height

Width

Depth

*Includes running gear & bottle tray.

TABLE 1. SPECIFICATIONS

MIGMASTER 250

250 Amps @ 27 Volts d.c.

50% @ 60 Hz.; 40% @ 50 Hz.

35% for 208 through 400V; 50% for 460 & 575V

Single Phase 208/230; 208/230/380/400/460/575 Volts 50 60 Hz

208-71, 230-62, 380-37,400-36, 460-31, 575-25

30 to 280 Amps.

55 v.d.c.

Push

0.023 inch (.6mm) 0.035 inch (.899mm)

0.030 inch (.762mm) 0.045 inch (1.143mm)

20-650 IPM

Air

45 degrees

200 w/Argon Mixtures, 300 w/CO

2 see section 2.3.1

*210 lbs (95 Kg.)

*32.25 inches (819 mm)

*19.5 inches (495 mm)

*40.0 inches (1016 mm)

2.3.4 MT-200cc WELDING TORCH (F-15-085),

The lightweight air cooled welding gun included in selected systems is supplied complete and ready to weld

0.035 in. steel wire. It is built with a one piece service conduit and includes a 45 degree gooseneck. Changing the contact tip to 0.045 in. allows the use of the larger wire.

2.3.5 CONTROLS

The Migmaster 250 System can be used to weld hard and aluminum wire with an optional ST-23A spool-gun torch.

An optional spot/stitch control allows a welder to spot or stitch weld within a range of 0.4 to 3.5 seconds. The builtin spool-on-gun adaptors and control, when used in conjunction with the optional ST-23A torch, permits aluminum wire welding with the machine.

2.3.6 RUNNING GEAR

The Migmaster 250 is equipped with a running gear w/ swiveled front wheels and a gas cylinder support. The rear wheels are packed loose for shipping, but are easily installed, see Section 3.8.

2.4 OPTIONAL ACCESSORIES

2.4.1 SPOT/STITCH/ANTI-STICK MODULE, P/N

32858.

This easy-to-install, plug-in module mounts in place of the lower blank cover plate of the upper-right front panel location in the 250 unit. It enables the operator to use the

250 for Spot or Stitch or Continuous welding operations.

It also includes an adjustable Anti-Stick feature that allows you to select various wire burnback times to prevent wire from sticking in the puddle after a weld. For installation, see Section 3.9 and for operating instructions see Section 4.2.

7

If a Spotwelding operation is to be used, it is recom-

mended that you also order a #12S Spotweld Nozzle,

P/N 999625.

2.4.2 DIGITAL VOLT/AMMETER MODULE, P/N 32857.

This easy-to-install, plug-in module mounts in place of the top blank cover plate of the upper-right front panel location in the 250 unit. This unique meter module alternately displays welding voltage and current (of the dial-set welding condition) every 4-seconds. Two L.E.D.’s labeled Amps and Volts provided below the meter windows, alternately illuminate to indicate which condition is being displayed. The voltage indication is displayed in 1/

10-volt increments (e.g.: 20.5), while the current indication is usually displayed in three-whole digits (e.g.: 225).

After the torch trigger is released, the meter will continue

to flash for 45-seconds the last condition used during welding. At the end of this time, the meter will reset to zero. For installation see Section 3.10.

2.4.3 ST-23A SPOOL-ON-GUN TORCH, P/N 19164

(see F-14-353).

The Migmaster 250 unit is equipped with a built-in control for the ST-23A Spool-On-Gun welding torch. The ST-

23A is a high performance, 250 ampere continuous duty spool-on-gun torch designed for the mig welding process. It is completely portable (up to 30-ft.), air-cooled and hand operated, and weighs less than three (3) pounds which allows for great maneuverability and operator convenience. The gun is equipped with twothirty (30) foot service lines; one is a control cable with amphenol plug, and the other is a gas and power cable with a screw-on connector. For installation and operation, see Section 4.1.7 and for detailed instruction booklet refer to F-14-353.

2.4.4 TORCH NOZZLES

A No. 8 Nozzle (1/2" I.D.), P/N 998893 to fit the MT-

200CC Torch, is included in the Migmaster 250 package.

This slip-on type nozzle includes a permanently mounted insulator/spatter shield. The following standard duty slipon nozzles, also equipped with the insulator/spatter shield, are available:

No. 6 Nozzle, Tapered (3/8" I.D.) ............ P/N 998895

No. 10 Nozzle (5/8" I.D.) ......................... P/N 998894

No. 12S Spotweld Nozzle (3/4" I.D.) ......... P/N 17316

Additionally, the following heavy-duty slip-on nozzles, also equipped with the insulator/spatter shield, are available:

No. 8 Nozzle (1/2" I.D.) ........................... P/N 999471

No. 10 Nozzle (5/8" I.D.) ......................... P/N 999472

No. 12 Nozzle (3/4" I.D.) ......................... P/N 999473

No. 12 Spot Nozzle (3/4" I.D.) ................ P/N 999625

2.4.5 TORCH/WIRE FEED ACCESSORIES -- See

Tables 2.4.5.1 and 2.4.5.2.

TABLE 2.4.5.1 Recommended MT-200cc Torch Accessories

Wire Contact Tips

Size & Type Short (S) Medium (M) Long (L)

Hard Wires & Cored Wires

.023" (.6mm) -

.030" (.8mm)

.035" (.9mm)

-

-

.045" (1.2mm) 999578

.052" (1.4mm) 948340

1/16" (1.6mm) 948341

20543

20544

996995

996999

2075349

996997

999742

996994

996996

996998

-

-

10'

999743*

948850

2075237

2075237

2075239

2075239

Liners

12'

-

17717

17718

17718

17719

17719

15'

-

-

2075238

2075238

2075240

2075240

Soft Wires (aluminum)

.035" (.9mm) -

3/64" (1.2mm) 999578

996995

996999

996996

996998

948862

948863 -

-

-

-

(S) Short contact tips are recommended for proper wire stick out for flux cored wire welding.

(M) Medium contact tips are recommended for proper wire stick out in spray transfer Mig welding.

(L) Long contact tips are recommended for good visability and proper wire stick in dip transfer

Mig welding.

* Requires support liner for .023" wire. Order P/N 999797.

Table 2.4.5.2 Guide Tubes/Feed Rolls

Wire Guide Feed

Size & Type Tube Roll

Hard Wires - "V" Groove

.023" (.6mm) 21163

.030" (.8mm) 21164

.035" (.9mm) 21165

.045" (1.2mm) 21165

.

21155

21155

21156

21156

Cored Wires - Serrated

.030" (.8mm) 21164

.035" (.9mm) 21165

.045" (1.2mm) 21165

.052" (1.4mm) 21166

1/16" (1.6mm) 21166

21160

21160

21161

21161

21161

Soft Wires (aluminum) - "U" Groove

.035" (.9mm) 21167* 21158

3/64" (1.2mm) 21168* 21158

* Requires support tube. Order P/N 21169

8

2.5 SAFETY

Before the equipment is put into operation, the safety section at the front of this manual should be read completely. This will help avoid possible injury due to misuse or improper welding applications.

The symbol which precedes safety notes appearing throughout this manual means “Attention! Be Alert!

Your safety is involved.” The definitions relating to the

DANGER, WARNING and CAUTION safety notations are described at the end of the Safety Section in the front of this manual -- read them and their specific text references carefully.

‡

III. INSTALLATION

3.1 LOCATION (Figure 3.1)

A proper installation site should be selected for the welding machine, if the unit is to provide dependable service and remain relatively maintenance free.

A proper installation site permits freedom of air movement into and out of the welding machine, and also least subjects the unit to dust, dirt, moisture, and corrosive vapors. A minimum of 18 inches (46 cm) unrestricted space must be maintained between the welding machine side and rear panels and the nearest obstruction.

The installation site should also permit easy removal of the welding machine outer enclosure for maintenance functions.

ˆ

‡

19

1/2"

ˆ

‡

40"

Figure 3.1 Dimensional Drawing

3.2 ELECTRICAL INPUT CONNECTIONS

ˆ

It is recommended that a line disconnect switch be installed in the input circuit to the welding machine.

This would provide a safe and convenient means to completely remove all electrical power from the welding machine whenever it is necessary to perform any internal function on the unit. (See Figure 3.2A.)

CAUTION: Do not place any filtering device over the intake air passages of the welding machine as this would restrict the volume of intake air and thereby subject the welding machine internal components to an overheating condition and subsequent failure.

Warranty is void if any type of filtering device is used.

If a forklift vehicle is used for lifting the unit, be sure that the lift forks are long enough to extend completely under the base.

Do not operate the machine without the running gear installed.

Before making electrical input connections to the welding machine, “Machinery Lockout Procedures” should be employed. If the connections are to be made from a line disconnect switch, the switch should be padlocked in the off position. If the connection is made from a fusebox, remove the fuses from the box and padlock the cover in the closed position. If locking facilities are not available, attach a red tag to the line disconnect switch (or fuse box) to warn others that the circuit is being worked on. If the plug-cap is used, (see 3.2B) remove plug from receptacle.

9

A. Input Electrical Requirements

Models of this welding machine are designed to be operated from 208/230, or 208/230/380/400/460/575 volts single phase 50/60 Hz, depending on model. The primary input voltage requirements are shown on the welding machine nameplate.

B. Input Conductor Connections

The input power cord on 208/230 Volts primary input model is provided with an attachment plugcap. The plugcap will mate with a 250 Volts, 50 Ampere receptacle conforming to NEMA 6-50 R configuration.

The receptacle should be wired to a separately fused disconnect or circuit breaker of the size listed in Table

3.1. This disconnect or breaker can be wired to a single phase system or to two conductors of a three phase system. A third conductor for grounding should also be connected between the disconnect and the receptacle.

Figure 3.2A illustrates wiring to a single phase system and Figure 3.2B illustrates wiring to a three phase system.

The 208/230/380/400/460/575 primary input voltage unit is provided with a three conductor primary input cable without plugcap. The ground lead of this cable should be connected to a reliable ground and the two remaining wires should be connected to the separately fused lines of the disconnect or breaker as shown in Figures 3.2C

and 3.2D.

All machines leave the factory with their primary electrical input requirements internally-connected for the highest voltage rating available in each model (e.g.: 230-volt for the 208/230-volt units; and 575-volt for the "multivoltage" units).

TABLE 3.1 Input Conductor and Fuse Size

Primary

Input

Full

Load

Recommended

Primary

Input Ground

Line Fuse Conductor Conductor

Volts Amperes Size Size Size

208

230

380

400

460

575

71

62

37

36

31

25

90

90

50

50

40

30

8

8

10

10

12

12

8

8

10

10

12

12

Only qualified personnel should make these changes. Make certain the primary power has been discoonnected and all safety procedures have been followed before proceeding with these instructions.

Fig. 3.3A shows the 230v and 208v connections for the

208/230 dual voltage model. Change over is made by removing the right side panel below the wire feed compartment and switching the primary transformer tap at the top of the power switch with the unused alternate voltage tap located next to the main transformer (see

Fig. 3.3B). Both voltage taps (the one currently connected to the switch and the unused alternate voltage) are marked with the input voltage requirement. All units are supplied from the factory connected for the highest voltage (230 vac). Before switching the voltage taps, verify the actual voltage requirement as well as the current voltage connection to be certain re-connection is necessary. If voltage tap re-connection is necessary, the following paragraphs cover the procedure to switch the voltage tap for either 208vac or 230vac input.

GRD

208/230 MODEL ONLY (With Plug-Cap)

SINGLE-PHASE

Fused

Line

Disconnect

Switch,

GRD or

Circuit Breaker

THREE-PHASE

Wall Receptacle

208/230/380/400/460/575-V. MODELS

GRD

SINGLE-PHASE

GRD

THREE-PHASE

GREEN

Figure 3.2 A

MIGMASTER

SYSTEM

CONNECTS HERE

Figure 3.2 B

Figure 3.2 C

Figure 3.2 - Primary Connection

10

GREEN

CONDUCTOR

(GROUND)

Figure 3.2 D

When changing the input voltage connections, the unused lead must be insulated and positioned to prevent contact with any other internal components of the machine or the machine side panel. The clearance between the unused lead and other components must be at least one inch (see Fig. 3.3B for illustration of the proper position). FAILURE TO

INSULATE AND POSITION THIS LEAD PROPERLY

WILL CAUSE A SERIOUS SHOCK HAZARD.

Figure 3.3A - Primary Reconnections at Switch

For 208/230 Volt Models

The terminal labeled GRD is connected to the welding machine chassis and is for ground purposes only. It must be connected to a good electrical ground. Do not connect a conductor from the terminal labeled GRD to any one of the L1, L2 terminals as this will result in an electrically hot welding machine chassis.

C CONNECTING FOR 208 VAC INPUT

After the panel is removed, locate the 208 Vac lead (Fig.

3.3B) and cut the tie-wrap to remove the insulation sleeving (on early models this lead may have been wrapped with black electrical tape). Open the insulating cover around the power switch (Fig. 3.3C.) to expose the terminals and disconnect the 230 Vac lead from the top of the switch as shown in Fig. 3.3A. Insulate the 230 Vac lead that was removed from the power switch with sleeving or approved electrical tape and re-position to a safe area beside the transformer (see Fig. 3.3B), leaving a minimum of one inch clearance from other components and the side panel.

D CONNECTING FOR 230 VAC INPUT

After the panel is removed, locate the 230 Vac lead (Fig.

3.3B) and cut the tie-wrap to remove the insulation sleeving (on early models this lead may have been

11

Fig. 3.3B - Position of Alternate Voltage Tap

Fig. 3.3C - Power Switch Connection

wrapped with black electrical tape). Open the insulating cover around the power switch (Fig. 3.3C.) to expose the terminals and disconnect the 208 Vac lead from the top of the switch as shown in Fig. 3.3A. Insulate the 208 Vac lead that was removed from the power switch with sleeving or approved electrical tape and re-position to a safe area beside the transformer (see Fig. 3.3B), leaving a minimum of one inch clearance from other components and the side panel.

Connect the proper voltage (208 Vac or 230 Vac) tap to the power switch and tighten securely. Check all other leads connected to the power switch for tightness and clearance from internal components before securing the insulating cover around the power switch. Replace the side panel.

PRIMARY VOLTAGE CONNECTION CHART

VOLTAGE CONNECTION

1 - 2

208 6 - 7

7 - 8

230

380

400

1 - 2

6 - 7

5 - 8

3 - 7

4 - 8

2 - 6

460

575

7 - 8

2 - 6

4 - 8

2 - 3

4 - 8

NO. OF STRIPS

1

1

FLEX

1

1

FLEX

2

FLEX

2

FLEX

2

FLEX

2

FLEX

Figure 3.3.1-Primary Reconnections at Voltage

Changeover Terminal Board for 208/230/380/400/460/

575Volt Models

E. Reconnecting from 575 VAC Input

Figure 3.3.1 shows you how to reconnect the "multivoltage" model from a 575-volt input to any of the remaining available voltage inputs 200 or 380 or 400 or

460-volts. These connections are made by unscrewing the right side panel below the wire feeding compartment, and locating the primary voltage changeover terminal board handing in the center of the lower compartment.

This board contains copper links which must be reconnected to match the silk-screened voltage designations for the input you plan to use (it comes factory-connected for a 575-volt input), see Figure 3.3.1.

3.3 SECONDARY OUTPUT CONNECTIONS

The Migmaster 250 Welding System is completely selfcontained so that the front panel torch fittings (Euro-type

MT and Spool gun) are internally connected to the welding polarity (D.C. Reverse or D.C. Straight) via the secondary output terminals located inside the wire feeding compartment (see Fig. 4.1). The machine comes set up for D.C.R.P. welding as described in Section 4.1.3.

3.4 TORCH CONNECTIONS

The torch (MT-200cc), which is supplied as standard equipment with the Migmaster 250 System, is provided with a euro-type adapter which directly connects to the torch fitting mounted on the front panel. Line up matching holes, push on and tighten locking collar. As shipped from the factory, the euro or common connector type torches are set-up for D.C.R.P. welding polarity (see sections 3.3 or 4.1.3). To connect the spool-on-gun torch

(ST-23A) see Section 4.2.2.

3.5 WIRE FEEDER MECHANISM

3.5.1 DRIVE ROLLS

The drive roll has two grooves: the small groove feeds

0.035 in. diameter wire, the large groove feeds 0.045 in.

wire. The groove nearest the gear motor feeds the wire.

If the required groove is not in that position:

A. Release the pressure drive roll lever and lift the assembly upward.

B. Remove the two (2) screws holding the drive roll to the gear.

C. Reverse the drive roll on the drive roll shaft.

D. Replace the screws and tighten.

E. Secure the pressure drive roll assembly.

12

3.5.2 WELDING WIRE SPOOL

As with any work area, make sure safety glasses with side shields are worn when handling or changing wire or clipping wire off at the spool or at the end of the torch. Hold onto the wire coming off the spool with one hand before clipping. Serious eye injury can result due to the springiness of the wire which can quickly unravel, or a cut wire end which may shoot across the room.

Install a spool of welding wire on the hub as follows:

A. Unscrew spool nut from hub.

B. Place wire spool on hub to rotate clockwise as wire is unwound; hub pin must engage hole in spool.

C. Replace nut.

3.5.3 THREADING WELDING WIRE

A. Turn off power switch.

When the power switch is on, and gun trigger is depressed, the electrode wire becomes electrically hot, and the wire feed rolls are activated.

B. Release pressure drive roll assembly and lift up ward. Check that proper wire diameter groove is in the inner position.

CAUTION: Before threading welding wire through casing, make sure chisel point and burrs have been removed from wire end to prevent wire from jamming in gun casing or liner.

C. Feed the wire from the spool through the inlet guide, across the drive roll groove and into gun outlet guide.

Make sure that the proper “outlet guide tube” is inserted into the front-panel gun fitting for the size and type of wire being used, see Table 2.4.5.2 for wire feed accessories

(Section 2.4.5).

To insure proper wire feeding, it is important that the wire be kept clean and that the drive rolls be periodically cleaned of any chips or scale that might be carried into the gun liner and cause sticking.

D. Lower pressure roll assembly and secure. Check that the gears mesh. Feed wire through to gun tip with gun trigger (power ON).

3.5.4 BRAKE DRAG ADJUSTMENT

Brake disc friction should provide enough drag to keep the wire spool or core from spinning freely after wire feed stops. If adjustment is required, turn adjusting screw clockwise to increase drag, counterclockwise to decrease it. Drag should be just low enough to limit wire overrun.

3.6 CONNECTION OF SHIELDING GAS SUPPLY

The R-33-FM-580 Regulator-Flowmeter is designed for use with an argon or argon-mix cylinder of shielding gas.

It is adjustable for delivering up to 50 cfh through the torch. To set up the system do the following:

Do Not adapt R-33-FM-580 for use with CO

2

. Relief device may rupture if CO

2

is used with the R-33-FM-

580.

a. With the cylinder cap in place CAREFULLY slide the cylinder of gas onto the Migmaster 250 cylinder rack.

b. Secure the cylinder to the unit, using the chain provided.

c. Unscrew the cylinder cap.

d. Open the cylinder valve slightly, just for an instant, to blow away any dirt or dust which may have accumulated in the cylinder valve outlet. Be sure to

keep your face away from the valve outlet to protect your eyes.

e. Attach the regulator to the cylinder valve, tighten the union nut securely with a 1-1/8in. open end or an adjustable wrench.

CYLINDER

VALVE

CYLINDER

PRESSURE

GAUGE

OUTLET

CONNECTION

Fig. 3.6 R-33-FM-580 Regulator

f. Attach the gas hose from the rear of the Migmaster

250 to the regulator outlet connection (see Fig. 3.6).

g. Slowly open the cylinder valve a fraction of a turn.

When the regulator pressure gauge pointer stops moving, open the cylinder valve fully.

13

Never stand directly in front of or behind the regulator when opening the cylinder valve. Always stand to one side.

h. Using a leak test solution, such as P/N 998771 (8 oz. container) or soapy water, test for leakage about the cylinder valve stem, the regulator inlet connection, and the hose connections at the regulator and at the Migmaster 250 for leakage. Correct any leaks before starting work.

i. If work is to be stopped for a half-hour or more, or the regulator is to be removed from the cylinder, shut down the regulator as follows: a. Close the cylinder valve.

b. Release gas from the regulator by closing the torch trigger lever.

c. When pressure gauge drops to zero, the regulator is de-pressurized and shutdown.

j. Each regulator is equipped with a porous metal inlet filter, P/N 71lZ33, pressed into the regulator inlet nipple. No. regulator should be connected to a cylinder or station valve unless it contains this filter. You can replace the filter if you have reason to do so. To remove a filter refer to the regulator instruction literature for details.

k. Regulators in need of repair should be returned to your Welding Equipment distributor or to an authorized Remanufacturing Center.

If welding is performed in a confined area, shielding gas leaks could result in a buildup of shielding gas concentration, displacing oxygen, thereby endangering personnel enter the area.

3.7

Connect the work clamp solidly to the workpiece or work table. Clamp onto a bare metal area.

A good electrical connection to the work is essential to proper welding operation and to prevent electric shock.

Welding cables should be kept as short as possible and be of adequate current carrying capacity. Resistance of the welding cables and connections causes a voltage drop which is added to the voltage drop of the arc.

Excessive cable resistance may result in a reduction of the maximum usable current output of the equipment.

The proper operation of this equipment is to a large extent dependent on the use of welding cables and connections which are in good condition and of adequate size.

3.8 ASSEMBLE REAR WHEELS

The unit's running board is factory assembled except for the rear wheels which are packed loose in the shipping carton. The rear gear consists of 2-wheels, 4-washers,

2-cotter pins, and an axle. To install the gear, do the following: a. Insert the axle through the holes provided at the rear of the gear.

b. Place a washer onto each end of the axle, then slip on the wheels, then add another washer to the outside of each wheel, and secure the whole assembly by inserting a pin in each end of the axle.

c. Remove the existing shipping supports by unscrewing from chassis.

3.9

INSTALLING OPTIONAL SPOT/STITCH/ANTI-

STICK MODULE

a. Remove lower blank-cover plate from upper-right front panel of power supply -- save the four mounting screws.

b. Locate the harness-connected 15-pin plastic plug,

P3, inside the mounting cavity. Note that this plug will have a jumper plug with jumper wires connected to it -- remove (and save) the jumper plug.

(The jumper plug must be reinstalled if the module is ever removed.

c. Connect the 15-pin plug into the matching receptacle on the rear of the optional control module. The plug will only fit one way.

d. Install the control module in place of the blank panel removed in Step a., using the same four screws that you saved.

3.10 INSTALLING OPTIONAL DIGITAL METER

a. Remove the top blank-cover plate from the upperright front panel of the power supply -- save the four mounting screws.

14

b. Locate the harness-connected 10-pin plastic plug,

PL1, inside the mounting cavity. This plug does

not have a jumper plug connected to it.

c. Connect the 10-pin plug into the matching receptacle on the rear of the optional meter module.

d. Install the meter module in place of the blankpanel removed in Step a., using the same four screws that you saved.

IV. OPERATION

4.1 CONTROLS (See Figure 4.1)

4.1.1 POWER SWITCH

A line toggle switch on the front panel energizes the primary of the main transformer. This switch also turns on the fan, which is connected across a portion of the primary winding.

Two transformer secondary windings also become energized:

A. Gun trigger circuit 24 volts AC.

Wire feeder circuit 24 volts DC.

B. Main welding secondary circuit. Depending upon the tap switch position, various secondary voltages can be obtained. Then rectified, open circuit voltages can be selected between 18 and 56 volts

DC when the secondary contactor is energized.

4.1.2 VOLTAGE CONTROL (Coarse Range Selector and Fine Adjustment Range Selector)

Voltage control is by means of two high current tap switches which connect the rectifier bridge to various secondary taps.

The COARSE VOLTAGE RANGE Selector is a threeposition switch, LOW/MED/HIGH, by which the operator selects the approximate range of voltage (or heat, that determines the arc length) to be applied to the weld. It is a coarse selection control and is used in conjunction with the Fine Voltage Adjustment selector following. It must

not be switched under load.

4.1.5

2.4.2

4.2.3

4.2.2

Secondary Output Terminals for Welding Polarity Changeover, see 4.1.3.

10A. Fuse

4.1.6

4.1.2

4.1.1

4.1.3

Work

Cable

Torch

Cable

15

The FINE VOLTAGE ADJUSTMENT Selector is an eight-position switch by which the operator selects the exact amount of arc voltage (or heat) to be applied to the weld (within the coarse range selected above). This allows you to fine-tune the voltage required; the higher the number selected (1-8), the hotter the weld. The Fine

Voltage Selector switch also has an "open" detent at the six o'clock position. Placing the switch in this position allows operation of the torch trigger to feed electrode wire without the wire being electircally "hot". This switch also, must not be switched under load.

CAUTION: These tap switches carry several hundred amperes, and must not be switched under load, as this will cause the contacts of the switches to arc.

4.1.3 SECONDARY WELDING CONNECTIONS

The secondary contactor, with parallel poles, is used to make and break the circuit between the transformer secondary and the rectifier. This contactor is turned on and off when the torch trigger (in the 24 volt circuit) is operated.

The secondary output welding terminals, POS.(+) and

NEG(-), are located in the right side wire feeding compartment and are used to set the welding polarity

(D.C.R.P. or D.C.S.P.) in which the machine will operate

(see Fig. 4.1). As shipped from the factory, the 250 is set up to operate in D.C.R.P. (TORCH fitting is connected to Positive, and WORK cable/clamp is connected to

Negative output). To weld using D.C.S.P., simply mount the WORK cable to the Positive output and the TORCH fitting cable to the Negative output terminal.

4.1.4 CONTACTOR CONTROL

Refer to the schematic diagrams. Note that the coil of the 24 volt contactor is activated with the torch trigger and is energized when the trigger is pulled. The gas solenoid is in parallel with the contactor coil and is energized at the same time.

When the trigger switch is released, the contactor drops out and disconnects the load.

Because of the charged capacitor bank in the secondary circuit, the output voltage will take a few seconds before falling to zero volts.

The gas valve shuts off when the contactor opens.

16

4.1.5 WIRE FEED SPEED CONTROL

Wire feed speed is controlled by the wire speed potentiometer knob on the front panel. The solid state control allows for infinitely variable speeds up to 650 IPM.

This wire speed pot is used to set the speed at which the welding wire is fed out from the torch and hence the welding amperage. The panel-face numbers on the dial

(0-10) are used for reference and do not directly indicate wire feed speed; the higher the number, the faster the speed.

4.1.6 STD./SPOOL GUN SELECTOR

This two-position toggle switch is located inside the unit on the mid-wall of the wire feeding compartment and is labeled Standard and Spool Gun. It is used to select standard metal inert gas welding (MIG) with the MT-

200CC, or welding with the ST-23A (spool-on-gun) torch.

4.2 PROCESS SETUP

4.2.1 STANDARD MIG SEAM WELDING W/MT-200CC

Refer to Sections 4.3.1, 4.3.2, 4.3.3, 4.3.4, and Table

4.3.3.

4.2.2 ST-23A SPOOL-ON-GUN CONTROL CONNEC-

TION/OPERATION

The Migmaster 250 is equipped with a built-in control for the Spool Gun which operates via the amphenol control receptacle and a screw adaptor that provides Gas and

Power. The ST-23A Torch (see Section 2.4.3) has a amphenol-plug control cable connection, and a gas/ power cable, see Figure 4.2.2.

To operate the unit with the ST-23A Torch connected, do the following (refer to Fig. 4.2.2):

A. Place the STD./Spool Gun selector toggle switch

(4.1.6) in the 250 to its Spool Gun position.

B. Connect the ST-23A control cable amphenol to the receptacle labeled CONTROL on the 250’s front panel.

C. Remove the threaded plastic plug from the Gas/

Power adaptor (on the 250's front panel) using a clockwise rotation. Connect the ST-23A gas/power cable to the panel adaptor using a counterclockwise rotation. As shipped from the factory, the 250's secondary output power terminals are set-up for D.C.R.P. welding polarity (see Section

4.1.3). IMPORTANT -- Always make sure that the plastic plug is screwed back into the adaptor when the ST-23A gas/power cable is disconnected, because hielding gas will escape from the adaptor unless the gas cylinder is shut-off.

Figure 4.2.2 - Connecting Spool-On-Gun to Services

D. Connect the 250’s WORK cable to the workpiece.

E. Set Migmaster 250 voltage tap switches to

RANGE and FINE ADJUSTMENT VOLTAGE settings desir- ed.

F. Turn on the Migmaster 250’s power switch and begin seam mig welding.

If the optional Spot/Stitch/Anti-Stick control module is installed, the ST-23A gun may be operated using these optional features, see Section 4.2.3.

4.2.3 OPTIONAL SPOT/STITCH/ANTI-STICK CON-

TROL MODULE

This optional control module allows the operator to use the 250 for Spot or Stitch or Continuous welding operations. It also includes an adjustable Anti-Stick feature to select various burnback times to prevent wire from sticking in the puddle after a weld.

The module consists of three pots (one for Spot-Stitch

Weld Time "ON", one for Stitch Weld Time "OFF", and one for Anti-Stick Time modes) and one three-position toggle switch to select the welding operation desired

(Spot, Continuous or Stitch). For installation, see Section

3.9; for operation, see following:

4.2.3.1 ANTI-STICK WELDING OPERATION

Anti-Stick feature provides a time delay at the end of a weld from the time the torch trigger is released until the main contactor is deenergized. This delay allows the welding wire to burn back, away from the work, so it won’t “stick” in the weld puddle.

This delay time, controlled by the “anti-stick” potentiometer, is variable from approximately 0.05 seconds to 0.5

seconds. The required delay time generally depends on the WIRE SPEED Adjustment setting on the front panel

- the higher the setting, the faster wire will feed into the weld, and the more delay time will be required.

If, when using the Anti-Stick feature, the welding wire tends to stick in the puddle at the end of a weld, the Anti-

Stick time should be increased; if, on the other hand, the wire burns back into the torch tip, the anti-stick time should be decreased. Setting the anti-stick time to “Min” effectively cancels the anti-stick feature.

This Anti-Stick feature is available for all three welding modes - Continuous, Spot, and Stitch.

4.2.3.2 CONTINUOUS WELDING MODE OPERATION

A. Place the three-position toggle switch in “Continuous” weld mode (center position) for mig seam welding.

B. Set the “Anti-Stick Time” as required (see 4.2.3.1).

17

C. Set the “coarse” and “fine” Voltage control switches and wire speed pot to the desired settings and begin welding operation as described in Sections 4.3.2 and 4.3.3.

4.2.3.3 SPOT WELDING MODE OPERATION

A. Place the three-position toggle switch in “Spot” position.

B. Replace the standard nozzle with the No. 12 Spot weld Nozzle P/N 999625.

C. Trim the welding wire back so the end is slightly inside the nozzle.

D. Set the “coarse” and “fine” voltage control switches, wire speed, and the Spot-Stitch Weld Time see

Table 4.3, for the thickness of the metal being welded and the diameter of the weld wire being used.

E. To spotweld: i. Press the torch nozzle squarely on the top plate.

Apply enough pressure to hold the two pieces of metal firmly together, so there is no loose play between them.

B. Be sure a standard nozzle (and not a spot weld nozzle) is installed on the torch.

C. Set the length of time the arc will be ON for each sequence by adjusting the Spot-Stitch Weld Time control  on  the  power  supply’s  front  panel. This timer has an approximate range of from 0.4 seconds at the minimum setting to 3.5 seconds at the maximum setting. Set the length of time the arc will be OFF for each sequence by adjusting the Stitch

Weld Time control on the front panel. This timer has an approximate range of from 0.4 seconds at the minimum setting to 3.5 seconds at the maximum setting.

D. Set the “coarse” and “fine” voltage control switches and wire speed as specified in Table 4.3 under

Continuous Weld Conditions for: i. The type weld being made (see diagrams to the left of each column of figures).

ii. The thickness of the metal being welded.

iii. The gap (if any) between the pieces being welded.

iv. The diameter of the welding wire being used.

E. When using the Stitch weld mode, before starting the weld the welding wire should extend about

1/ 2-in. beyond the end of the nozzle. Adjust this length by either clipping off the end of the wire with insulated cutters or by using the torch switch.

Fig. 4.2.3 - Cross Section of Good Spotweld

ii. Pull the trigger, holding the gun motionless and firmly. The electrode wire and shielding gas will be fed to the work, and the arc will be maintained for the length of time set in Step D. above.

iii. After the preset time has elapsed, the wire will stop feeding, the arc will be broken, and the shielding gas will stop flowing.

A good spotweld will penetrate through both layers of metal, and will have a small nugget on the reverse side, (Fig. 4.2.3)

4.2.4 STITCH WELDING MODE OPERATION

A. Place the three-position toggle switch in “Stitch” position. The stitch weld mode uses a series of pretimed arc-on/arc-off time sequences to allow cooler welding.

Power supply contactor becomes energized the moment the torch trigger is depressed. Arcing can occur if the wire is brought to a ground. Keep the torch always from ground until welding is to begin.

F. During the welding, use the same welding techniques as described in Section 4.3.3 and 4.3.4.

4.2.5 DUTY CYCLE (Figure 4.2.5)

The duty cycle of the equipment is the percentage of a 10 minute period which it can operate safely at a given output current. The Migmaster system is rated at 50% duty cycle. This means that the equipment can be safely operated at 250 amperes for five minutes out of every 10.

This cycle can be repeated indefinitely (See Figure

4.2.5).

18

Fig. 4.2.5 Duty Cycle Curves

4.2.6 VOLT/AMPERE CURVES (Figure 4.2.6)

The Volt/Ampere curves show the output Voltage available at any given output current for the various Voltage

Selector positions in each range low, medium, and high.

The actual operating point of load Voltage and Current is determined by type of process, electrode, shield gas, wire feed speed, and operating technique.

Figure 4.2.6 VOLT/AMPERE CURVES

4.3 OPERATING PROCEDURES

4.3.1 OPERATING SAFETY PRECAUTIONS

Comply with all ventilation, fire and other safety requirements for arc welding as established in the SAFETY

Section at the front of this manual.

Also remember the following:

A. Because of the radiant energy of the welding arc and the possibility of drawing an arc before the helmet is lowered over the face, the operator should wear flash goggles with filter lenses under his helmet. The helmet filter plated should be shade number 11 (nonferrous) or 12 (ferrous). All those viewing the arc should use helmets with filter plates, as well as flash goggles. Nearby personnel should wear flash goggles.

B. The radiant energy of the arc can decompose chlorinated solvent vapors, such as trichloroethylene and perchlorethylene, to form phosgene, even when these vapors are present in low concentrations. DO NOT weld where chlorinated solvents are present in atmospheres in or around the arc.

C. DO NOT touch the electrode, nozzle or metal parts in contact with them when power in ON: all are electrically energized (HOT) and can cause a possibly fatal shock. DO NOT allow electrode to touch grounded metal: it will create an arc flash that can injure eyes. It may also start a fire or cause other damage.

D. When working in a confined space, be sure it is safe to enter. The confined space should be tested for adequate oxygen (at least 19%) with an approved oxygen measuring instrument. The confined space should not contain toxic concentrations of fumes or gases. If this cannot be determined, the operator should wear an approved air supplied breathing apparatus.

Avoid gas leaks in a confined space, as the leaked gas can dangerously reduce oxygen concentration in the breathing air.

DO NOT bring gas cylinders into confined spaces.

When leaving a confined space, shut OFF gas supply at the source to prevent gas from leaking into the space, if the switch is accidently kept depressed. Check the breathing atmosphere in the confined space to be sure it is safe to reenter.

19

E. Never operate the equipment at currents greater than the rated ampere capacity; overheating will occur.

F. Never operate equipment in a damp or wet area without suitable insulation for protection against shock. Keep hands, feet and clothing dry at all times.

G. Whenever the equipment is left unattended, turn all control and power supply switches and gas supplies OFF and open the main line switch.

H. Wear dark substantial clothing to protect exposed skin from arcburn, sparks and flying hot metal.

I. Turn off welding power before adjusting or replacing electrodes.

Never operate the welding machine with any portion of the outer enclosure removed. In addition to a hazard, improper cooling may result in damage to the welding transformer and the welding machine components. Warranty is void if the machine is operated with any portion of the outer enclosure removed.

4.3.2 PRE-WELD REQUIREMENTS

Before welding commences, with all power OFF, check the following:

A. All safety requirements have been read and under stood.

B. All hoses and cables are in good condition, safely

insulated and securely connected.

C. Turn on gas supply by slowly opening cylinder

valve to full ON.

D. Correct size wire accessories have been installed

on the wire feeder, drive gears are meshed, wire

pressure set, and guide tube is installed for type

and size wire you plan to use, refer to Tables

2.4.5, and 4.3..

E. Spool of correct size wire is locked in place, brake

tension is set, and wire is properly threaded through the inlet guide to the gun tip.

F. The wire feeding compartment cover is closed and secure.

G.Make sure that the metal to be welded is properly

prepared: a. Remove loose surface rust, scale or paint with wire brush or sander.

20 b. Attempting to weld over grease or oil can cause weld defects.

c. Before welding on aluminum, be sure to clean surface thoroughly using a stainless steel brush.

4.3.3 SET-UP PROCEDURE

A. Determine the material type, thickness and joint configuration to be welded from Table 4.3 and use the recommendations to set the following: a. Coarse Voltage Range, LOW/MED/HIGH.

b. Fine Arc Voltage Setting, 1 thru 8 (the higher the number, the hotter the weld).

c. Wire Speed setting, 0 thru 10 (the higher the number, the faster the speed).

B. Set the two-position switch in the wire feeder compartment to STANDARD for seam welding with the

MT-200CC torch. (For ST-23A Spool-On-Gun welding, see Section 4.2.2).

C. If optional Spot/Stitch/Anti-Stick Control module is installed, refer to Section 4.2.3 for operation, settings and welding condition table.

D. Make sure the MT-200CC torch fitting and the

“Work” cable are connected to the proper output terminals (inside unit) for the polarity desired.

Only qualified personnel should make these changes.

Make certain the primary power has been disconnected and all safety procedures have been followed before proceeding with these instructions.

Normally, you will set-up for “reverse polarity”; this means the torch fitting is connected to the POS (+) output terminal and the “Work” cable to the NEG

(-) output terminal.

For “straight polarity”, do just the opposite; torch fitting to NEG (-) output terminal and “Work” cable to POS (+) output terminal.

4.3.4 WELDING OPERATION

A. Turn Power switch (on unit) to ON position -- be careful not to operate the torch switch.

B. Before starting the weld, the welding wire should extend about 1/2-inch beyond the end of the nozzle.

Adjust this length by either clipping off the end of the wire with insulated cutters or by using the torch switch.

Power supply contactor becomes energized the moment the torch trigger is depressed. Arcing can occur if the wire is brought to a ground. Keep the

torch away from ground until welding is to begin.

C. To start the weld, hold the torch so the welding wire is approximately 1/4-in. from the work, then press the torch trigger.

D. The welding wire should be pointed into the joint at angles of approximately 45 approxmately 90

0

0

for fillet welds, and

for butt welds, (Fig 4.3.4.1).

E. The torch angle relative to the length of the weld should be approximately 10

0

from the vertical (Fig. 4.3.4.2).

F. When welding in the vertical position, traveling either up or down, it is very important to keep the arc on the leading edge of the puddle to ensure complete penetration.

G. Some welders who are accustomed to welding with stick electrodes may tend to push the torch into the weld. This is neither necessary nor desirable, since the wire electrode is being mechanically fed into the weld.

Please note that the Wire Speed control can be adjusted for the gauge of metal to be welded. How-

ever, the Coarse Voltage Range and Fine Voltage

setting must not be switched while welding.

H. To stop the weld, release the trigger and pull the torch from the work. When leaving equipment unattended, always shut OFF and disconnect all input power and shut off shielding gas at source.

TABLE 4.3, Continuous/Stitch Weld Conditions

Fig. 4.3.4.1 - Angle of Welding Wire with Joint

21

SETTING

SHOWN AS:

Arc

Voltage

Voltage Range

Wire Feed

Speed

MIG PROCESS SELECTION GUIDE

MIG PROCESS SELECTION GUIDE

TO SET MACHINE

1.

Find the thickness of the base plate to be welded.

2.

Find the diameter of the filler wire to be used.

3.

Find the suggested arc voltage, range and wire feed setting by following the wire diameter row across (to the right) and the plate thicknesses column down.

4.

Set the arc voltage selector switch, voltage range switch and the wire feed pot to the settings indicated.

WIRE

DIAMETER

.023"

CARBON STEEL BASE PLATE THICKNESS

24 GA. 20 GA.

18 GA.

16 GA.

3/32" 1/8"

SHORT CIRCUITING ARC

3/16" 1/4" 3/32" 1/8" 3/16"

SPRAY ARC

1

LOW

1.2

2

LOW

1.3

3

LOW

2.5

4

LOW

3

6

LOW

4.3

1

MED

6.5

4

MED

10

1/4"

.030"

.035"

.045"

4

LOW

3

3

LOW

1.8

4

LOW

3.5

4

LOW

2

4

LOW

1.8

7

LOW

4

6

LOW

3

5

LOW

2

7

LOW

4.5

6

LOW

3.8

6

LOW

2

8

LOW

5

1

MED

4

6

LOW

2.8

2

MED

5.5

2

MED

4.5

3

MED

3

5

MED

6

5

MED

5.5

8

MED

4

6

MED

6.5

5

MED

5.5

8

MED

4

7

MED

6.8

6

MED

6

2

HIGH

4.2

4

HIGH

8.5

6

MED

6

2

HIGH

4.2

Settings were developed using 75% argon - 25% carbon dioxide shielding gas.

For 100% carbon dioxide shielding gas, add 2 to the arc voltage setting shown above.

Settings were developed using 98% argon - 2% oxygen shielding gas.

TABLE 4.3, Continuous /Stitch Weld Contitions

This equipment is provided with a thermostat (OL) in the transformer (T1) windings which will open and prevent the contactor (CON) from closing if the transformer windings are overheated. If the thermostat opens, allow the equipment to idle with fan running for approximately

15-min. before attempting to weld again.

V. SERVICE

5.1 MAINTENANCE

Be sure the branch circuit or main disconnect switch is off or electrical input circuit fuses are removed before attempting any inspection or work on the inside of the welding machine. Placing the power switch on the welding machine in the OFF position does not remove all power from inside of the equipment.

5.2 INSPECTION AND SERVICE

Keep Equipment in clean and safe operating condition free of oil, grease, and (in electrical parts) liquid and metallic particles which can cause short-circuits.

Regularly check cylinder valves, regulators, hoses, and gas connections for leaks with soap solution.

Check for and tighten loose hardware including electrical connection. Loose power connections overheat during welding.

Immediately replace all worn or damaged power cables and connectors. Check for frayed and cracked insulation, particularly in areas where conductors enter Equipment.

The electrode wire and all metal parts in contact with it are electrically energized while welding. Inspect these parts periodically for defective insulation and other electrical hazards.

Inspection, troubleshooting and repair of this equipment may ordinarily be undertaken by a competent individual having at least general experience in the maintenance and repair of semi-conductor electronic equipment. Maintenance or repair should not be undertaken by anyone not having such qualifications.

If uninsulated cable and parts are not replaced, an arc caused by a bared cable or part touching a grounded surface may damage unprotected eyes or start a fire. Body contact with a bared cable, connector, or uncovered conductor can shock, possible fatally.

Shut OFF shielding gas supply at source.

To aid in checking and servicing, use Schematic, Figure

5.1.

22

Keep power cables dry, free of oil and grease, and protected at all times from damage by hot metal and sparks.

Clean dirt and metal particles from drive roll groove weekly; replace roll if badly worn.

5.2.1 POWER SOURCE

5.2.1.1 RECTIFIER

It is recommended that the rectifier be cleaned occasionally by blowing it out with compressed air. This cleaning operation is necessary so that maximum cooling will be accomplished by the air stream. This should be done periodically, depending upon the location of the unit and the amount of dust and dirt in the atmosphere.

The hermetically sealed silicon diode rectifiers are specially designed for welding machine use and will not age or deteriorate in use. The four diodes are mounted on heat sinks. A periodic cleaning of dust and dirt from these is necessary to insure cooling of the rectifiers. Access is by removal of top cover and side panels. Should any diode accidentally be damaged and need replacement, it can be quickly removed from the heat sink. The replacement diode should be of the same type as the one removed, and should be locked securely to the sink, preferably with a torque wrench set for maximum of 25 ft.

lbs. and a minimum of 20 ft. lbs. Excessive torque will distort the mechanical structure and may break the hermetic seal, whereas too little torque will result in improper electrical connections.

NOTE: Thermal conductive compound (Wakefield Engineering #120 Thermal Compound or equivalent) must be reapplied to heat sink-diode mating surface whenever a diode is replaced.

5.2.1.2 FAN MOTOR

All models are equipped with an exhaust fan and rely on forced draft for adequate cooling for high duty cycles and overloads. Lubricate the fan motor with a few drops of

SAE-20 non-detergent oil every three months.

5.2.1.3 TRANSFORMER

Occasional blowing out of the dust and dirt from around the transformer is recommended. This should be done periodically depending upon the location of the unit and the amount of dust and dirt in the atmosphere. The welding machine case cover should be removed and a clean, dry air stream should be used for this cleaning operation.

5.2.1.4 24 VOLTS WIRE FEEDER AND CONTROL

CIRCUITS

The 24-volts circuit is protected by a 10 amp fuse in a panel mounted fuseholder, accessible from the wire feeder compartment. Failure of this fuse will shut off the contactor, shielding gas and wire feeder.

If it should become necessary to replace this or any other fuse in the welding machine, ensure that the proper size fuse is used as a replacement.

5.2.1.5 OVER-TEMPERATURE PROTECTION

The machine is equipment with a thermostat. On continued high current application, if the thermostat reaches an abnormally high temperature, it will deenergize the contactor. This thermostat will reset itself automatically after the transformer windings have cooled to a safe level. While deenergized, neither the contactor, shielding gas nor wire feeder can be operated.

5.2.2 WIRE FEEDER

When soft wire is fed, the drive rolls may pick up metal from the wire surface. Accumulation on the rolls may score the wire with resulting unwanted friction and improper feeding.

Inspect the rolls regularly and clean them with a fine-wire power brush. Avoid roughening, or removing the hardness of groove surfaces in grooved rolls. Any roughening may score the wire, just as the accumulation being removed may do.

5.3 TROUBLESHOOTING

If welding equipment doesn’t work right despite compliance with checklist inspect as follows:

A. With all power controls ON and other operating controls at required settings, visually check all power cables and connections for evidence of overheating or sparking.

To avoid shock, do NOT touch electrode wire or parts in contact with it, or uninsulated cable or connections.

B. Check all gas (and water) hoses and connections, flowmeters, and regulators for possible sources of leakage, breakdown or intermittent failure.

C. Isolate trouble to one part of the welding installation: primary power supply, power source, Feeder or wire guide train (casing, drive rolls, liners and contact tip). If this inspection indicates trouble in the Feeder, use Troubleshooting Guide, Table II and schematic diagram (Figure 5.1).

23

5.3.1 IF MOTOR DOES NOT RUN:

A. Check for blown fuse. If blown, check that motor is not binding before replacing fuse.

B. Check for continuity across speed potentiometer

(POT) and wiper contact. Voltage from center tap to MIN end should vary from 0 to 5.4 VDC as potentiometer is rotated clockwise.

C. Check wiring for continuity. Then turn power ON and check for 30 volts d.c. across input terminals

8 and 9 on the feeder printed circuit board connector (PL1).

D. Press torch trigger, and check for voltage across motor (Pins 4 to 7) of speed control board; should vary from 1 to 24 VDC as speed control potentiometer is rotated clockwise.

5.3.2 DRIVE ROLL PRESSURE ADJUSTMENT

Adjust the drive roll pressure knob until no wire slippage occurs. DO NOT OVERTIGHTEN - EXCESSIVE PRES-

SURE CAN CAUSE WIRE FEEDING PROBLEMS.

General Replacement

The exploded views in the Parts Section indicate generally, in numbered parts sequence, the disassembly of the wire drive and feeder parts.

Reassemble in reverse order.

5.3.3 SOLENOID VALVE REPLACEMENT

When replacing the gas solenoid valve, the inlet (with the word IN) must face the rear of the Unit.

Many troubleshooting situations require that the power remain On and that power terminals in the equipment carry voltage. Exercise extreme caution when working on “LIVE” equipment. Avoid contact with electrical components, except when testing with an appropriate instrument.

Do not make any repairs to equipment unless you are fully qualified, as described in the maintenance section.

WELD CONDITION

1. No weld or control power.

2. No welding power.

3. Fan does not run.

4. Erratic welding current.

5. Welding output Voltage and/or current too low.

TABLE II. TROUBLESHOOTING GUIDE

POSSIBLE CAUSE REMEDY

a. Primary input power not available.

a. Check for Voltage at primary input.

b. Faulty connection, primary input cable, or power switch (TGS1) c. Blown line fuse.

b. Repair or replace cable or switch

(TGS1) as necessary.

c. Replace fuse. If it blows again, contact L-TEC representative.

a. Thermostat has opened.

b. Shorted diode in main rectifier.

c. Open in wiring a. See Weld Condition 1.

b. Defective fan motor (MTR1) a. Wait 15 minutes with fan running. If still no power, contact L-TEC representative.

b. Check diodes and replace if req’d.

c. Check all wiring.

a. Repair or replace cable or switch as necessary.

b. Replace fan motor (MTR1).

a. Poor workpiece connection.

b. Loose welding connections.

c. Wrong polarity.

a. Low line Voltage.

b. Welding cables too long or too small.

a. Check workpiece grounding connection.

b. Check all connections.

c. Check for correct polarity.

a. Use correct Voltage.

b. Use correct cable size.

24

WELD CONDITION

6. Stringy irregular bead, poor penetration.

7. Bead not centered.

8. Bead too large.

9. Unstable arc, excess spatter, weld porous.

10.Shield gas flow low or stopped

POSSIBLE CAUSE

c. Loose connection.

d. Defective capacitor bank.

a. Torch moved too fast.

b. Controls are not set properly for metal gauge thickness.

c. Wrong polarity.

a. Nozzle not aligned.

a. Torch moved too slowly.

a. Incorrectly set controls.

b. Shield gas flow is too low or stopped.

c. Torch nozzle is too far from work.

d. Faulty regulator or adapter.

e. Faulty gas solenoid valve (SOL).

f. Wrong polarity.

a. Cylinder valve closed.

b. Cylinder empty.

c. Faulty regulator or adaptor.

d. Faulty gas solenoid valve.

REMEDY

c. Check all welding cable connections.

d. Check capacitors for low leakage resistance.

a. Move Torch slower along seams.

b. Reset control properly.

c. Check for correct polarity.

a. Move Torch nozzle parallel to and centered over seam.

a. Move Torch faster along seam.

a. Reset controls.

b. See Condition 10.

c. Maintain 1/4" (.6 cm) wire protrusion; hold closer to work.

d. Check flow at outlet; replace faulty item.

e. Replace solenoid valve.

f. Check polarity.

a. Turn off regulator, slowly open valve, until regulator reaches

35 c.f.h. pressure.

b. Replace if gauge so indicates.

c. Check flow at outlet; replace faulty item.

d. Replace solenoid valve.

11.Wire stubs on work while welding.

a. Controls not set properly for metal gauge, thickness.

a. Reset controls properly.

12.Wire burns back into contact tip.

13.Wire does not feed; motor running (drive roll turns).

a. Contact tip loose.

b. Tip too close to work.

c. Wire feed slipping.

d. Contact tip damaged.

a. Firmly tighten with pliers.

b. Maintain 1/4" (.6 cm) wire protrusion; hold Torch further from work.

c. Increase pressure on pressure roll by adjusting pressure knob.

d. Trim back tip 1/16" (1.6 cm) max.

Replace if still faulty.

e. Voltage setting too high.

e. Adjust setting.

f. Drive or pressure roll dirty or worn.

f. Clean rolls or replace.

a. Kink, etc. in wire, or wire bound on reel.

b. Wire freezing to contact tip

(burnback).

c. Clogged liner.

a. Straighten; or feed wire until clear and cut off.

b. Free freeze, or remove contact tip feed wire until clear cut end free, and replace tip.

c. Replace liner.

25

WELD CONDITION

14.Wire does not feed; motor NOT running

(drive roll does not turn).

POSSIBLE CAUSE

a. Motor b.Power switch TGS1 and fuses.

c. Speed Potentiometer (POT).

d. Defective speed control board.

15.Wire feed does not stop.

a. Torch trigger switch.

16.Gas continues to flow after trigger release.

b. CR1 a. Gas solenoid valve stuck open.

REMEDY

a. With wire speed dial on 10, press trigger. If voltage appears across motor leads but motor does not run, check motor gears and commutator areas.

b. With TGS1 ON, if voltage across terminal 1 and 3 is 24 VAC, switch and fuses are good.

c. Check for 1K ohms across

POT outside terminals.

d. Check board voltages

(Para 5.3.1 b. and c.) a. Check continuity of Torch trigger circuit; check to see if trigger lever is stuck in “ON” position.

b. Check for proper action.

a. Tap solenoid or click on and off to clear valve.

VI. PARTS

6.1 SPARE PARTS

To assure minimum downtime, it is recommended that the spare parts noted by the symbol (*) in the Stock No.

column of the parts list be kept on hand.

6.2 REPLACEMENT PARTS

The following illustrations of the equipment identify each replacement part by item number as tabulated in the related parts lists. The list identifies each part by part, number, description, and quantity used (in parentheses, if more than 1). Some assemblies can be ordered as complete units or broken down as individual parts.

These parts are listed - indented one space - below the assembly. When any of the parts can be broken down as a sub-assembly, its individual parts as listed below it indented two spaces.

Attaching hardware items are listed, deeply indented, below the part they attach. They may not be shown.

Order them separately.

6.3 ORDERING

To assure proper operation, it is recommended that only genuine ESAB parts and products be used with this equipment. To order replacement parts: a. Give the part number, description and quantity of each part required.

b. Give part number and description of equipment on which the parts are to be used.

c. Indicate any special shipping instructions.

26

27

28

29

30

24

21

FAN/CAPACITOR

BANK ASSEMBLY

See Figure 6.4

}

20,

19

17

18

16

14

13

12

1

11

4

5,

25

6,

7

22,

23

8

10

FIGURE 6.1 MIGMASTER 250 MAIN ASSEMBLY (Left Side)

14

15

16

17

18

19

­

20

21

22

23

24

25

7

8

10

11

12

13

ITEM QTY.

NO. REQ.

1

4

5

6

1

1

1

1

1

1

2

3

7

2

1

1

1

1

3

2

1

1

1

1

2

1

1

PART

NO.

33184

672225

1373 6750

33176

951634

1373 0628

951633

2360 6726

1373 2230

950396

1373 0912

1373 0222

951672

950695

31484

2360 8111

1373 5940

950760

2361 0322

1373 0469

1373 4781

1373 0665

9951 2178

2360 9967

674216

1371 5289

1373 1989

DESCRIPTION (Figure 6.1)

BASE

INSULATOR STANDOFF

TRANSFORMER, MAIN - for 208/230 v. model

TRANSFORMER, MAIN - for 208-575 v. model

VALVE, SOLENOID, 24 V(from 1/1/94)

VALVE, SOLENOID (before 1/94)

CONNECTOR, "Y" from 1/1/94)

HOSE CONNECTION (before 1/94)

CAPACITOR 10,000 MT, 50V

CASTER, SWIVEL 5"

WHEEL

BUSHING

HANDLE (from 1/1/94)

HANDLE (from 1/94)

P.C. BOARD, SPEED CONTROL

TERMINAL BLOCK, 8 PT

MARKER, TERMINAL

RELAY (from 1/1/94)

RELAY, 4 PDT, 24 VAC, 10A

BRIDGE, RECTIFIER

CONTACTOR (see Note below)

BUSBAR “E” STAMPING

RESISTOR, 50 OHM, 50W

TERMINAL, 3 POS

CAPICATOR .02uf 1KV

RESISTOR 1 OHM 25W

THERMOSTAT 145°

CKT.

DESIG.

T1

T1

SOL1

C 1-7

TB1

K2, K3

K1

R3

TB3

C9-11

R5

TS1

Capacitor C9-11 and R5 resistor were added 4/93 (starting with Serial No. B93H36548) to provide greater relay protection.

­

NOTE: If contactor, 13734781, life is short due to high current, repetitive welding, replace with 60 amp contactor, 952173.

31

7

13,

14

11, 12

8

18, 19

10

15

6

20

3

5

21, 22

23, 24

2

16, 17

FIGURE 6.2 MIGMASTER 250 SYSTEMS

ITEM QTY

NO. REQ.

16

17

18

19

12

13

14

15

20

21

22

23

24

7

8

10

11

5

6

2

3

1

1

2

1

2

1

1

1

1

1

1

1

1

1

1

1

1

2

1

1

1

PART

NO.

33188

950769•

1373 0623

33192

33291

33189

33187

2360 3918

1373 4681

32818

2062171

647233

2062171

32902

951069

680552

950721

21165

2361 2350

2361 0696

2361 0528

DESCRIPTION (Figure 6.2)

PANEL, SIDE, RIGHT

STRAIN, RELIEF

LATCH, DOOR

PLATE, COVER*

COVER, HINGED

PANEL, CONTROL, SILKSCREENED

PANEL, SIDE, LEFT

POTENTIOMETER, IK

KNOB

SWITCH ASS'Y., SINGLE POLE, 8 POS.

KNOB

RECEPTACLE, 8 PIN

KNOB

SWITCH ASS'Y., SINGLE POLE, 3 POS.

PLUG, PLASTIC "C" SIZE

ADAPTOR, (SPOOL ON GUN)

SWITCH, TOGGLE

GUIDE TUBE

POWER LUG

ADAPTOR BLOCK ASS'Y.

HOUSING, ADAPTOR (STRAIGHT)

CKT.

DESIG.

* Photo shows optional Digital Volt/Ammeter Module, P/N 32857, and Spot/Stitch/Anti-Stick Control Module, P/N 32858.

• Was 97W63, changed to 950769, 6/95.

32

11

19

7,

6

14

5

9, 10

3

2

1

18

20

17

15

16

ITEM QTY

NO. REQ.

11

14

15

16

17

18

19

20 l

6

7

9

10

3

5

1

2

2

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

PART

NO.

+ -

+ -

+ -

33186

2360 5057

2360 6237

634519

1373 5464

1373 1072

2361 2348

2361 2479

33199

2361 2627

82F31

1373 2232

951649

33450

676701

97W63

FIGURE 6.3 MIGMASTER 250 MAIN ASSEMBLY (Right Side)

CKT.

DESIG.

DESCRIPTION (Figure 6.3)

REAR, PANEL

SUPPORT, REEL

HUB, REEL (See Figure 6.5)

SWITCH, TOGGLE, 4 PDT

FUSE, 10A

HOLDER, FUSE

GEAR MOTOR, 50-675 IPM

KEY, MOTOR SHAFT

COVER P.C. BOARD

DRIVE STAND ASSEM. (See Fig. 6.6)

WORK CLAMP

FILTER, CHOKE

POWERCORD

BUSHING, TERMINAL

TERMINAL ASS'Y., OUTPUT

STRAIN RELIEF

TGS2

FU1

TP

+ - DENOTES RECOMMENDED ON HAND SPARE PART

l

- Added "D" Edition, 3/96

33

10, 9

2

2

5

4, 3

6

ITEM QTY.

NO. REQ.

6

9

10

4

5

2

3

2

1

1

4

2

2

4

6

FIGURE 6.4 MIGMASTER 250 FAN & CAPACITOR BANK

PART

NO.

1373 0377

1373 0680

1373 0681

1373 1597

1373 0378

1373 2227

1373 2226

DESCRIPTION (Detail "B" FAN)

DIODE, SILICON, STRAIGHT POLARITY

INSULATOR, COLLAR

INSULATOR, SHOULDER

WELDMENT, RESISTOR

DIODE, SILICON, REVERSE POLARITY

BLADE, FAN

MOTOR, FAN

CKT.

DESIG.

D1, D2

D3, D4

M1

8

9

REF.

7 6 5 4

1 2

ITEM QTY.

NO.

REQ.

7

8

5

6

9

3

4

1

2

1

1

1

1

1

1

1

1

1

PART

NO.

2360 5780

2360 0255

2360 6237

2360 0982

2360 0010

9204 0101

9205 6007

2360 0952

2360 5057

FIGURE 6.5 MIGMASTER 250 LEXAN HUB KIT

DESCRIPTION (HUB KIT)

REEL HUB KIT (INCLUDES 1-8)

BRAKE, DISC

HUB, REEL

SPRING

NUT

SCREW, R.H.M., 3/8-16 x .75

WASHER, PLAIN

WASHER, "D"

SUPPORT, REEL

SHELF (REF.)

34

3

CKT.

DESIG.

Item

No.

9

10

11

12

13

14

15

7

8

5

6

3

4

1

2

16

17

18

19

20

21

Qty

Req.

1

1

1

1

1

1

2

1

1

1

1

1

2

5

1

1

1

1

1

1

1

1

Part

No.

23612627

23612626

23612387

23612475

23612385

23612470

23612472

23612397

23612386

23612460

23612473

23612461

21156

23612383

23612398

23612478

23612479

23612480

23612384

23612462

23612662

23612663

Figure 6-6. 2-Roll Drive Stand

Description

2 ROLL GEARED WIRE DRIVE SYSTEM, CONSISTS OF:

PRESSURE ARM ASSY., (incls. 2, 3, 4, 7, 8)

AXLE, PRESSURE ROLL

PRESSURE ARM

CIRCLIP, PRESSURE ROLL

PIVOT PIN

CIRCLIP

PRESSURE ROLL, SMOOTH

GEARED ADAPTOR, PRESSURE ROLL

PRESSURE DEVICE ASSY.

LOCATING PIN

INLET GUIDE

DRIVE ROLL, .035" - .045"

GEARED ADAPTOR DRIVE ROLL

FEED ROLL RETAINING SCREW

FEED PLATE

FEED ROOL KEY

MOTOR SHAFT SNAP RING (Not Shown)

LOCATING SCREW

SCREW

SPACER TUBE (Pressure Arm)

SPRING PRESSURE ARM

35

ESAB Welding & Cutting Products, Florence, SC Welding Equipment

COMMUNICATIONS GUIDE - CUSTOMER SERVICES

A. CUSTOMER SERVICE QUESTIONS: Telephone (803) 664-5540/Fax: (800) 634-7548

Order Entry

Order Changes

Product Availability

Saleable Goods Returns

Pricing

Delivery

Hours: 8:30 AM to 5:00 PM EST

Shipping Information

B. ENGINEERING SERVICE: Telephone: (803) 664-4416 / Fax : (800) 446-5693

Welding Equipment Troubleshooting

Warranty Returns Authorized Repair Stations

Hours: 7:30 AM to 5:00 PM EST

C. TECHNICAL SERVICE: Telephone: (800) ESAB-123/ Fax: (803) 664-4452

Part Numbers Technical Applications Hours: 8:00 AM to 5:00 PM EST

Performance Features Technical Specifications Equipment Recommendations

D. LITERATURE REQUESTS: Telephone: (803) 664-5501 / Fax: (803) 664-5548

Hours: 7:30 AM to 4:00 PM EST

E. WELDING EQUIPMENT REPAIRS: Telephone: (803) 664-4469 / Fax: (803) 664-5557

Repair Estimates Repair Status Hours: 7:30 AM to 3:30 PM EST

F. WELDING EQUIPMENT TRAINING:

Telephone: (803)664-4428 / Fax: (803) 664-4476

Training School Information and Registrations

G. WELDING PROCESS ASSISTANCE:

Telephone: (803) 664-4248 / Fax: (803) 664-4454

Hours: 7:30 AM to 4:00 PM EST

Hours: 7:30 AM to 4:00 PM EST

H. TECHNICAL ASST. CONSUMABLES:

Telephone: (800) 934-9353 Hours: 7:30 AM to 5:00 PM EST

IF YOU DO NOT KNOW WHOM TO CALL

Telephone: (800) ESAB-123/ Fax: (803) 664-4452/Web: http://www.esab.com

Hours: 7:30 AM to 5:00 PM EST

F-15-087-E 8/97 5M