MK Products Cobramatic 120VAC User Manual

Product Description Cobramatic®

MK Manual Part Number 091-0495

MK Form Number CB/OM-5

NWSA Form Number 550

Effective with Serial

Number

Voltage Rating 115 VAC

Printing/Rev. Date August 2002 D

This manual applies to the

following model numbers

12001

150-005

Cobramatic® Wire Feed Cabinet

16882 Armstrong Ave., Irvine, CA 92606 Tel 949/863-1234 Fax 949/474-1428 www.mkproducts.com

SAFETY CONSIDERATIONS

ELECTRIC ARC WELDING EQUIPMENT

CAUTION : READ BEFORE ATTEMPTING INSTALLATION, OPERATION

OR MAINTENANCE OF THIS EQUIPMENT

1-1 INTRODUCTION

This equipment is intended for ultimate application by commercial/industrial users and for operation by persons trained and experienced in the use and maintenance of welding equipment. Operation should not be undertaken without adequate training in the use of such equipment. Training is available from many public and private schools or similar facilities.

Safe practices in the installation, operation and maintenance of this equipment requires proper training in the art, a careful study of the information provided with the equipment, and the use of common sense. Rules for safe use are generally provided by suppliers of welding power sources, compressed gas suppliers, and electrode suppliers. Careful compliance with these rules will promote safe use of this equipment.

The following Safety Rules cover some of the more generally found situations. READ THEM CAREFULLY. In case of any doubt, obtain qualiﬁ ed help before proceeding.

1-2 GENERAL PRECAUTIONS

A. B

URN PREVENTION

ELECTRIC ARC WELDING PRODUCES HIGH INTENSITY HEAT AND ULTRAVIOLET RADIANT ENERGY WHICH MAY CAUSE SERIOUS AND PERMANENT EYE DAMAGE AND WHICH MAY DAMAGE ANY EXPOSED SKIN AREAS.

Wear helmet with safety goggles or glasses with side shields underneath, appropriate ﬁ lter lenses or plates (protected by clear cover glass). This is a must for welding or cutting (and chipping) to protect the eyes from radiant energy and ﬂ ying metal. Replace cover glass when broken, pitted, or spattered.

Medical ﬁ rst aid and eye treatment. First aid facilities and a qualiﬁ ed ﬁ rst aid person should be available for each shift unless medical facilities are close by for immediate treatment of ﬂ ash burns of the eyes and skin burns.

Wear protective clothing - leather (or asbestos) gauntlet gloves, hat, and high safety-toe shoes. Button shirt collar and pocket ﬂ aps, and wear cufﬂ ess trousers to avoid entry of sparks and slag.

Avoid oily or greasy clothing. A spark may ignite them.

Flammable hair preparations should not be used by persons intending to weld or cut.

Hot metal such as electrode stubs and work pieces should never be handled without gloves.

Ear plugs should be worn when working on overhead or in a conﬁ ned space. A hard hat should be worn when others work overhead.

OXIC FUME PREVENTION

B. T

WARNING: The use of this product may result in exposure to chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

Adequate ventilation. Severe discomfort, illness or death can result from fumes, vapors, heat, or oxygen enrichment or depletion that welding (or cutting) may produce. Prevent them with adequate ventilation. NEVER ventilate with oxygen.

Lead-, cadmium-, zinc-, mercury-, beryllium-bearing and similar materials, when welded or cut, may produce harmful concentrations of toxic fumes. Adequate local exhaust ventilation must be used, or each person in the area, as well as the operator, must wear an air-supplied respirator. For beryllium, both must be used.

Metals coated with or containing materials that emit toxic fumes should not be heated unless coating is removed form the work surface, the area is well ventilated, or the operator wears an air-supplied respirator.

Work in a conﬁ ned space only while it is being ventilated and, if necessary, while wearing an airsupplied respirator.

Gas leaks in a conﬁ ned space should be avoided. Leaked gas in large quantities can change oxygen concentration dangerously. Do not bring gas cylinders into a conﬁ ned space.

Leaving conﬁ ned space, shut OFF gas supply at source to prevent possible accumulation of gases in the space if downstream valves have been accidentally opened or left open. Check to be sure that the space is safe before reentering it.

Vapors from chlorinated solvents can be decomposed by the heat of the arc (or ﬂ ame) to form PHOSGENE, a highly toxic gas, and other lung and eye irritating products. The ultraviolet (radiant) energy of the arc can also decompose trichloroethylene and perchloroethylene vapors to form phosgene. DO NOT WELD or cut where solvent vapors can be drawn into the welding or cutting atmosphere or where the radiant energy can penetrate to atmospheres containing even minute amounts of trichloroethylene or perchloroethylene.

C. F

IRE AND EXPLOSION PREVENTION

Causes of ﬁ re and explosion are: combustibles reached by the arc, ﬂ ame, ﬂ ying sparks, hot slag, or heated material, misuse of compressed gases and cylinders, and short circuits.

BE AWARE THA T ﬂ ying sparks or falling slag can pass through cracks, along pipes, through windows

or doors, and through wall or ﬂ oor openings, out of sight of the goggled operator. Sparks can ﬂ y many feet.

To prevent ﬁ res and explosion: Keep equipment clean and operable, free of

oil, grease, and (in electrical parts) of metallic particles that can cause short circuits.

If combustibles are in area, do NOT weld or cut. Move the work if practicable, to an area free of combustibles. Avoid paint spray rooms, dip tanks, storage areas, ventilators. If the work cannot be moved, move combustibles at least 35 feet away, out of reach of sparks and heat; or protect against ignition with suitable and snug-ﬁ tting, ﬁ re-resistant covers or shields.

Walls touching combustibles on opposite sides should not be welded on (or cut). Walls, ceilings, and ﬂ oor near work should be protected by heat-resistant covers or shields.

Fire watcher must be standing by with suitable ﬁ re extinguishing equipment during and for some time after welding or cutting if:

1. Appreciable combustibles (including building construction) are within 35 feet.

2. Appreciable combustibles are further than 35 feet, but can be ignited by sparks.

3. Openings (concealed or visible) in ﬂ oors or walls within 35 feet may expose combustibles to sparks.

4. Combustibles adjacent to walls, ceilings, roofs, or metal partitions can be ignited by radiant or conducted heat.

Hot work permit should be obtained before operation to ensure supervisor’s approval that adequate precautions have been taken.

After work is done, check that area is free of sparks, glowing embers, and ﬂ ames.

An empty container that held combustibles, or that can produce ﬂ ammable or toxic vapors when heated, must never be welded on or cut, unless container has ﬁ rst been cleaned in accordance with industry standards.

This includes: a thorough steam or caustic cleaning (or a solvent of water washing, depending on the combustible’s solubility), followed by purging and inerting with nitrogen or carbon dioxide, and using protective equipment.

Water-ﬁ lling just below working level may substitute for inerting.

A container with unknown contents should be cleaned (see paragraph above). Do NOT depend on sense of smell or sight to determine

Cobramatic® Safety - page i

if it is safe to weld or cut. Hollow castings or containers must be vented

before welding or cutting. They can explode. Explosive atmospheres. NEVER weld or cut

where the air may contain ﬂ ammable dust, gas, or liquid vapors (such as gasoline).

OMPRESSED GAS EQUIPMENT

D. C

The safe handling of compressed gas equipment is detailed in numerous industry publications. The following general rules cover many of the most common situations.

1. Pressure Regulators

Regulator relief valve is designed to protect only the regulator from overpressure; it is not intended to protect any downstream equipment. Provide such protection with one or more relief devices.

Never connect a regulator to a cylinder containing gas other than that for which the regulator was designed.

Remove faulty regulator from service immediately for repair (ﬁ rst close cylinder valve). The following symptoms indicate a faulty regulator:

Leaks - if gas leaks externally. Excessive Creep - if delivery pressure

continues to rise with downstream valve closed.

Faulty Gauge - if gauge pointer does not move off stop pin when pressurized, nor returns to stop pin after pressure release.

Repair. Do NOT attempt repair. Send faulty regulators for repair to manufacturer’s designated repair center, where special techniques and tools are used by trained personnel.

2. Cylinders

Cylinders must be handled carefully to prevent leaks and damage to their walls, valves, or safety devices:

Avoid electrical circuit contact with cylinders including third rails, electrical wires, or welding circuits. They can produced short circuit arcs that may lead to a serious accident. (See 1-3C)

ICC or DOT marking must be on each cylinder. It is an assurance of safety when the cylinder is properly handled.

Identifying gas content. Use only cylinders with name of gas marked on them; do not rely on color to identify gas content. Notify supplier if unmarked. NEVER DEFACE or alter name, number, or other markings on a cylinder. It is illegal and hazardous.

Empties: Keep valves closed, replace caps securely; mark MT; keep them separate from FULLS, and return promptly.

Prohibited use. Never use a cylinder or its contents for other than its intended use, NEVER as a support or roller.

Locate or secure cylinders so they cannot be knocked over.

Passageways and work areas. Keep cylinders clear of areas where they may be stuck.

Transporting cylinders. With a crane, use a secure support such as a platform or cradle. Do NOT lift cylinders off the ground by their valves or caps, or by chains, slings, or magnets.

Do NOT expose cylinders to excessive heat, sparks, slag, and ﬂ ame, etc. that may cause rupture. Do not allow contents to exceed 55 degrees C (130 degrees F.) Cool with water spray where such exposure exists.

Protect cylinders, particularly valves from bumps, falls, falling objects, and weather. Replace caps securely when moving cylinders.

Stuck valve. Do NOT use a hammer or wrench to open a cylinder valve that cannot be opened by hand. Notify your supplier.

Mixing gases. NEVER try to mix any gases in a cylinder.

NEVER reﬁ ll any cylinder. Cylinder ﬁ ttings should never be modiﬁ ed or

exchanged.

3. Hose

Prohibited use. Never use hose other than that designed for the speciﬁ ed gas. A general hose identiﬁ cation rule is: red for fuel gas, green for oxygen, and black for inert gases.

Use ferrules or clamps designed for the hose (not ordinary wire or other substitute) as a binding to connect hoses to ﬁ ttings.

No copper tubing splices. Use only standard brass ﬁ ttings to splice hose.

Avoid long runs to prevent kinks and abuse. Suspend hose off ground to keep it from being run over, stepped on, or otherwise damaged.

Coil excess hose to prevent kinks and tangles. Protect hose from damage by sharp edges, and by

sparks, slag, and open ﬂ ame. Examine hose regularly for leaks, wear, and loose

connections. Immerse pressured hose in water; bubbles indicate leaks

Repair leaky or worn hose by cutting area out and splicing. Do NOT use tape.

4. Proper Connections

Clean cylinder valve outlet of impurities that may clog oriﬁ ces and damage seats before connecting regulator. Except for hydrogen, crack valve momentarily, pointing outlet away from people and sources of ignition. Wipe with a clean, lintless cloth.

Match regulator to cylinder. Before connecting, check that the regulator label and cylinder marking agree, and that the regulator inlet and cylinder outlet match. NEVER Connect a regulator designed for a particular gas or gases to a cylinder containing any other gas.

Tighten connections. When assembling threaded connections, clean and smooth seats where necessary. Tighten. If connection leaks, disassemble, clean, and retighten, using properly ﬁ tting wrench.

Adapters. Use a CGA adapter (available from your supplier) between cylinder and regulator, if one is required. Use two wrenches to tighten adapter marked RIGHT and LEFT HAND threads.

Regulator outlet (or hose) connections may be identiﬁ ed by right hand threads for oxygen and left hand threads (with grooved hex on nut or shank) for fuel gas.

5. Pressurizing Steps:

Drain regulator of residual gas through suitable vent before opening cylinder (or manifold valve) by turning adjusting screw in (clockwise). Draining prevents excessive compression heat at high pressure seat by allowing seat to open on pressurization. Leave adjusting screw engaged slightly on single-stage regulators.

Stand to side of regulator while opening cylinder valve.

Open cylinder valve slowly so that regulator pressure increases slowly. When gauge is pressurized (gauge reaches regulator maximum) leave cylinder valve in following position: for oxygen and inert gases, open fully to seal stem against possible leak; for fuel gas, open to less than one turn to permit quick emergency shut-of

Use pressure charts (available from your supplier) for safe and efﬁ cient recommended pressure settings on regulators.

Check for leaks on ﬁ rst pressurization and regularly thereafter. Brush with soap solution. Bubbles indicate leaks. Clean off soapy water after test; dried soap is combustible.

E. U

SER RESPONSIBILITIES

Follow all Safety Rules. Remove leaky or defective equipment from

service immediately for repair. Read and follow user manual instructions.

F. L

EAVING EQUIPMENT UNATTENDED

Close gas supply at source and drain gas.

G. ROPE STAGING-SUPPORT

Rope staging-support should not be used for welding or cutting operation; rope may burn.

1-3 ARC WELDING

Comply with precautions in 1-1, 1-2, and this section. Arc Welding, properly done, is a safe process, but a careless operator invites trouble. The equipment carries high currents at signiﬁ cant voltages. The arc is very bright and hot. Sparks ﬂ y, fumes rise, ultraviolet and infrared energy radiates, weldments are hot, and compressed gases may be used. The wise operator avoids unnecessary risks and protects himself and others from accidents.

A. B

URN PROTECTION

Comply with precautions in 1-2. The welding arc is intense and visibly bright.

Its radiation can damage eyes, penetrate lightweight clothing, reﬂ ect from light-colored surfaces, and burn the skin and eyes. Skin burns resemble acute sunburn; those from gas-shielded arcs are more severe and

Cobramatic® Safety - page ii

painful. DON’T GET BURNED; COMPLY WITH PRECAUTIONS.

1. Protective Clothing

Wear long-sleeve clothing in addition to gloves, hat, and shoes. As necessary, use additional protective clothing such as leather jacket or sleeves, ﬂ ameproof apron, and ﬁ re-resistant leggings. Avoid outer garments of untreated cotton.

Bare skin protection. Wear dark, substantial clothing. Button collar to protect chest and neck, and button pockets to prevent entry of sparks.

2. Eye and Head Protection

Protect eyes from exposure to arc. Eyes may be damaged by radiant energy when exposed to the electric arc, even when not looking in the direction of the arc. Never look at an electric arc without protection.

Welding helmet or shield containing a ﬁ lter plate shade no. 12 or denser must be used when welding. Place over face before striking arc.

Protect ﬁ lter plate with a clear cover plate. Cracked or broken helmet or shield should

NOT be worn; radiation can be passed through to cause burns.

Cracked, broken, or loose ﬁ lter plates must be replaced IMMEDIATELY. Replace clear cover plate when broken, pitted, or spattered.

Flash goggles with side shields MUST be worn under the helmet to give some protection to the eyes should the helmet not be lowered over the face before an arc is struck. Looking at an arc momentarily with unprotected eyes (particularly a high intensity gas-shielded arc) can cause a retinal burn that may leave a permanent dark area in the ﬁ eld of vision.

3. Protection of Nearby Personnel

Enclose the welding area. For production welding, a separate room or enclosed bay is best. In open areas, surround the operation with low-reﬂ ective, noncombustible screens or panels. Allow for free air circulation, particularly at ﬂ oor level.

Viewing the weld. Provide face shields for all persons who will be looking directly at the weld.

Others working in area. See that all persons are wearing ﬂ ash goggles.

Before starting to weld, make sure that screen ﬂ aps or bay doors are closed.

OXIC FUME PREVENTION

B. T

Comply with precautions in 1-2B. Generator engine exhaust must be vented to

the outside air. Carbon monoxide can kill.

C. F

IRE AND EXPLOSION PREVENTION

Comply with precautions in 1-2C. Equipment’s rated capacity. Do not overload

arc welding equipment. It may overheat cables and cause a ﬁ re.

Loose cable connections may overheat or ﬂ ash

and cause aﬁ re. Never strike an arc on a cylinder or other pressure

vessel. It creates a brittle area that can cause a violent rupture or lead to such a rupture later under rough handling.

OMPRESSED GAS EQUIPMENT

D. C

Comply with precautions in 1-2D.

E. S

HOCK PREVENTION

Exposed electrically hot conductors or other bare metal in the welding circuit, or in ungrounded, electrically-HOT

equipment can fatally shock a person whose body becomes a conductor. DO NOT STAND, SIT, LIE, LEAN ON, OR TOUCH a wet surface when welding without suitable protection.

To protect against shock: Keep body and clothing dry. Never work in damp

area without adequate insulation against electrical shock. Stay on a dry duckboard, or rubber mat when dampness or sweat cannot be avoided. Sweat, sea water, or moisture between body and an electrically HOT part - or grounded metal reduces the body surface electrical resistance, enabling dangerous and possibly lethal currents to ﬂ ow through the body.

1. Grounding the Equipment

When installing, connect the frames of each unit such as welding power source, control, work table, and water circulator to the building ground. Conductors must be adequate to carry ground currents safely. Equipment made electrically HOT by stray currents may shock, possibly fatally. Do NOT GROUND to electrical conduit, or to a pipe carrying ANY gas or a ﬂ ammable liquid such as oil or fuel.

Three-phase connection. Check phase requirement of equipment before installing. If only three-phase power is available, connect single-phase equipment to only two wires of the three-phase line. Do NOT connect the equipment ground lead to the third (live) wire, or the equipment will become electrically HOT - a dangerous condition that can shock, possibly fatally.

Before welding, check ground for continuity. Be sure conductors are touching bare metal of equipment frames at connections.

If a line cord with a ground lead is provided with the equipment for connection to a switch box, connect the ground lead to the grounded switch box. If a three-prong plug is added for connection to a grounded mating receptacle, the ground lead must be connected to the ground prong only. If the line cord comes with a three-prong plug, connect to a grounded mating receptacle. Never remove the ground prong from a plug, or use a plug with a broken ground prong.

2. Connectors

Fully insulated lock-type connectors should be used to join welding cable lengths.

3. Cables

Frequently inspect cables for wear, cracks, and damage. IMMEDIATELY REPLACE those with excessively worn or damaged insulation to avoid possibly lethal shock from bared cable. Cables

with damaged areas may be taped to give resistance equivalent to original cable.

Keep cable dry, free of oil and grease, and protected from hot metal and sparks.

4. Terminals and Other Exposed Parts

Terminals and other exposed parts of electrical units should have insulating covers secured before operation.

5. Electrode Wire

Electrode wire becomes electrically HOT when the power switch of gas metal-arc welding equipment is ON and welding gun trigger is pressed. Keep hands and body clear of wire and other HOT parts.

6. Safety Devices

Safety devices such as interlocks and circuit breakers should not be disconnected or shunted out.

Before installation, inspection, or service of equipment, shut OFF all power, and remove line fuses (or lock or red-tag switches) to prevent accidental turning ON of power. Disconnect all cables from welding power source, and pull all 115 volts line-cord plugs.

Do not open power circuit or change polarity while welding. If, in an emergency, it must be disconnected, guard against shock burns or ﬂ ash from switch arcing.

Leaving equipment unattended. Always shut OFF, and disconnect all power to equipment.

Power disconnect switch must be available near the welding power source.

Cobramatic® Safety - page iii

For selecting a quality product. We want you to take

Thank You

pride in operating this product...as much pride as we have in bringing the product to you!

Please Examine Carton and Equipment For Damage Immediately

When this equipment is shipped, title passes to the purchaser upon receipt by the carrier. Consequently, claims for material damaged in shipment must be made by the purchaser against the transportation company at the time the shipment is received.

Please record your equipment identification information below for future reference. This information can be found on your machine nameplate.

Model Name & Number _____________________

Code & Serial Number _____________________

Date of Purchase _____________________

Whenever you request replacements parts for, or information on this equipment always supply the information you have recorded above.

Read this Owner’s Manual completely before attempting to use this equipment. Save this manual and keep it handy for quick reference. Pay particular attention to the safety instructions we have provided for your protection.

Cobramatic® Owner’s Manual - page iv

Table of Contents

Saftey Guidelines

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

Technical Speciﬁ cations .......................................................................1

Machine Grounding .............................................................................1

Machine Location ................................................................................1

Input Power Connections .....................................................................1

Wire Threading Procedure ...................................................................2

Welding Torch Connections ..................................................................4

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

General Description .............................................................................4

Recommended Processes and Equiment ...............................................4

Controls and Settings ..........................................................................4

POSA Start Operating Procedure...........................................................5

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

Optional Kits .......................................................................................7

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

Routine Maintenance ...........................................................................7

Testing the Feeder...............................................................................8

Testing the Torch ................................................................................9

Troubleshooting .................................................................Section E

Troubleshooting Guide .......................................................................10

Diagrams/Parts List ..........................................................Section F

Main PC Boards .................................................................................13

Mechanical .......................................................................................14

Electrical ...........................................................................................25

Warranty Repair Stations

Safety Warnings

Warranty

Cobramatic® Owner’s Manual

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Cobramatic® Owner’s Manual

Section A Installation

Technical Speciﬁ cations

Wire Diameter Capacity .......................................030 - 1/16” ALL Types

Wire Spool Capacity ...........................................12” Standard

(Insulated or Non-Insulated)

Power Input ......................................................... 115 VAC 50/60 Hz,

............................................................................... 150 Watts Peak (1.3 amps)

Weight ..................................................................41 pounds

Shipping Weight .................................................46 pounds

For Use with torch preﬁ x number .....................14X, 16X, 21X & 22X

Support Equipment Required

C.V. or C.C. Power Source of Sufﬁ cient Capacity for Regulated Gas Supply and Hoses. Properly Sized Power Leads from Power Source to Wire Feeder and Ground.

Coolant Recommendations

Coolant Recirculator and Hose Capable of Providing a Minimum of 1 qt/min. at 45 p.s.i. when using water cooled torches.

Use a name-brand additive which does not contain reactive sulphur or chlorine and does not react with copper, brass, or aluminum.

Check coolant periodically to remain within limits of the following:

A. Coolant Flow rate - 1 quart/minute at 45 p.s.i. B. Resistivity - 10K ohms/centimeter C. Ph Range - 5.5-8.5 D. Particle Size - .005”

MK Recommended Coolant Solution: 1 part ethylene glycol

3 parts distilled water 1 teaspoon liquid glycerin

Your Needs.

Machine Grounding

The Cobramatic® and GMAW wire feeders are ground to the power source through the input cable. The power source grounding terminal must be properly connected to electrical ground per the power source operating manual.

Mounting Location

The cabinet should be placed in a location where it can be protected from damage. Lead lengths and accessibility must also be considered when installing the cabinet.

Input Connections

(See Cabinet and Torch Hook-Up in the Appendix)

115 VAC

Your Wire Feeder comes factory ready with a standard 3-prong plug ready to connect into any standard 120VAC, 15 wired harnesses are available for different power supplies. See part numbers and description of each in the OPTIONAL KITS section of this manual.

The 115 VAC is connected to the PC Board on terminal strip J5 #1 (neutral) and #2 (hot) and Ground to the Cabinet chassis. See diagram in the appendix.

Cobramatic® Owner’s Manual - page 1

A receptacle. Several optional, pre-

Shielding Gas

In accordance with the required support equipment, the customer must provide a cylinder of shielding gas, a pressure regulator, a ﬂ ow control valve, and a hose from the ﬂ ow control valve to the left bottom-most ﬁ tting on the power block.

The end of the hose must have a male connector to ﬁ t the female 5/8-18 brass ﬁ tting. Use a 11/16” wrench to tighten.

Coolant Supply and Return (if used)

Using a recirculator with properly mixed coolant, as previously described, connect the coolant RETURN hose to the left middle ﬁ tting on the power block. Connect the coolant SUPPL

Y hose to the left top-most ﬁ tting on the

power block. The coolant hoses must have a male 5/8-18 left-hand thread to connect to the

power block ﬁ ttings. Use an 11/16” wrench to tighten.

Welding Power

The electrode cable coming from the welding power supply should be afﬁ xed with a 1/2” copper ring lug. Using a 9/16” wrench, remove the 3/8” bolt and washer from the bottom of the power block. Use a 9/16” wrench to tighten.

It is recommended to make this connection last, after connecting the gas and coolant hoses. Reference Input Connections ﬁ gure in the

Appendix.

Wire Threading Procedure

Wire Spool Installation

Release latches, and open right side door of cabinet. Remove spool retainer from spindle hub. Raise wire retainer bar to latched position. Install wire spool onto spindle hub so that wire feeds from bottom of spool

towards slave motor. Make sure that the hole in the spool aligns with pin on spindle hub. The white dot on the end of the spindle hub will aid in this alignment.

Replace the spool retainer nut. Lower the wire retainer bar onto the spool.

Wire Spool Drag Setting

NOTE:

Standard factory setting of the Spindle T

ension Knob is set for All Other Wires.

There are two visible position settings for this Knob, IN - All Other Wires (Fig. 1) and, OUT - .030/.035 Al Only (Fig. 2). The Spindle Tension Knob must be set to match the Wire Size Selector Switch on the Cobramatic® front panel.

IN - All other wires

Figure 1

Cobramatic® Owner’s Manual - page 2

OUT - .030/.035 Aluminum ONLY

Figure 2

To change this setting, it is easier done without the spool of wire on the spindle. Remove the wire spool retainer and re-install it reversed back onto the Spindle Tension Knob (Fig. 3). In the “Tool Mode”, the square shaped end of the retainer ﬁ ts onto the Knob. Grab the retainer and turn in the COUNTER- CLOCKWISE direction until it stops. The Knob is now set to the OUT position (.030/.035 AL Only).

Wire Spool Retainer In "Tool Mode";

used to change spindle drag.

Figure 3

To reset the Knob back to the factory setting of All Other Wires, use the retainer as described above, and turn in the CLOCKWISE direction until it stops. The Knob is now set to the IN position. Turning the retainer and Knob in this direction may require more effort, since turning CLOCKWISE is working against a spring.

Load wire spool onto spindle according to the previous instructions. Replace the spool retainer nut. Lower the wire retainer bar onto the spool.

Threading Procedure

Place wire size selector switch on front panel to the correct position for the wire being used.

Loosen end of wire from spool and cut off any kinked or bent portions. Unreel and straighten out ﬁ

rst 6” to 8” of wire. Raise wire type lever to center position. Route wire into inlet guide, along drive roll groove, and into wire conduit. Flip wire type lever to show type of wire being used. Tighten the torch pressure adjusting knob so the wire will be picked up and

fed through the contact tip. Proper tension is achieved when wire does not slip if a small amount of pressure is added to the wire as it exits the tip.

Wire Retainer Bar

The design of the patented Cobramatic® Wire Retainer Bar performs two very important and very basic functions of the wire feeder: a) spool drag tension, and b) wire maintenance on the spool.

The spool drag tension is set by lowering the wire retainer bar onto the wire inside of the spool. The spring tension of the wire retainer bar applies enough pressure on the spool so that when the torch trigger is released, engaging the brake pall, the spool does not overrun kicking wire of

f the spool.

Wire maintenance on the spool is performed by the applied pressure of the wire retainer bar spread across the coiled wire on the spool. The replaceable pad (P/N 437-0255) of the wire retainer bar is designed to hold the wire on the spool, maintaining the smooth layering of the wire and keeping it from jumping off, and possibly, electrically shorting to the cabinet chassis.

Cobramatic® Owner’s Manual - page 3

Welding Torch Connections

Work Cable

Connect a work lead of sufﬁ cient size and length (see table below) between the proper output stud on the power source and the work. Be sure the connection to the work makes tight metal to metal electrical contact. Poor work lead connections can result in poor arc initiation, poor weld results and activation of the ground lead protector

Work Lead Lengths Current 60% Up to 50ft. 10-100ft.

Duty Cycle (15.2m) (15.2-30.4m) 300A 0 (53mm) 0 (67mm)

400A 00 (67mm) 00 (85mm) 500A 00 (67mm) 00 (85mm) 600A 000 (85mm) 000 (107mm)

Control Cable

The 7-Pin “W” Clocked connector screws onto the mating receptacle on the front panel of the wire feeder. voltage, potentiometer control & trigger) to and from the feeder to the torch.

Wire Conduit Inlet

Front panel access to attach conduit to front of slave motor assembly.

Power Cable Inlet

Front panel access to attach power cable (air or water) to top of power block.

This provides all electrical signals (motor

Gas Inlet

Front panel access to attach gas hose to bottom ﬁ tting of power block.

Water Inlet (For Water Cooled Torches)

Front panel access to connect the water hose to the middle ﬁ tting on the power block.

Section B Operation

General

The AC slave motor in the feeder runs at a fast, constant speed, but has very low torque. It is always trying to feed more wire than the torch motor wants, and when the motor gets all it wants, it slows the slave motor preventing a bird’s nest. Because of the low torque produced by the slave motor, a brake system is used to prevent wire overrun rather than tension. The spool drag tension is produced by the patented Wire Retainer Bar mechanism to keep the wire slightly taut. The 24 VDC torch pull motor is controlled by a solid state speed control and a potentiometer located in the torch.

Recommended Processes and Equipment

The Cobramatic® is recommended for use in the GMAW and FCAW welding applications. It is recommended for use with constant voltage power sources. The Cobramatic® is capable of feeding wires (diameter capacity) ranging from .023” through .045” solid/cored and .030” through 1/16” aluminum.

Controls and Settings

On/Off Switch

Placing the switch in the “ON” position energizes the feeder circuitry and the power indicator light.

Wire Size Selector Switch

The wire size selector switch changes the torque of the slave motor for the wire you are using. When in the .030-.035 aluminum only position, the slave

Cobramatic® Owner’s Manual - page 4

motor produces approximately 1 1/2 lbs. inches and approximately 4 1/2 lbs. inches when in the all other wires position.

NOTE:

Operating the cabinet with the switch in the wrong

position will cause wir

e feed difﬁ culties.

Posa Start Controls

The Posa Start Run-in Speed Control, located on the front panel, provides adjustment for slow wire run-in. Once the arc has been established, the wire feed speed is automatically changed from the slow run-in speed to the welding speed set on the torch potentiometer.

Posa Start Operating Procedure

General

The Posa Start feature allows the Cobramatic® to be used in combination with constant current DC welding power sources of open circuit voltage in excess of 55 volts - also, any constant voltage welding power source capable of a minimum of 50 amps.

Main Board Con

ﬁ guration

Factory supplied, this switch will be shipped in the CV (Constant Voltage) position. This designates the type of welding power supply the Cobramatic is connected to. If the the power supply is a Constant Current type (CC), the switch should be moved to the CC position.

This switch is designed to conﬁ

gure the main board so that the OCV (Open CIrcuit Voltage) and welding current (measured at J1 current sensor) properly engages the PosaStart

cirtcuit to tranfer from the run-in wire speed to

welding wire speed. If the position of the switch does not match that of the power supply, the

PosaStart

circuit will not engage and wire speed transfer will not occur.

Cobramatic® Owner’s Manual - page 5

Note:

Reverse polarity MUST be used.

Posa Start Connections

Attach the #14 single black lead which extends from the back of the cabinet to the negative terminal of the power supply or work ground. The Posa Start lead is internally connected to the P

.C. board on terminal strip J6, terminal 2.

CV Posa Start Operations

Attach Cobramatic® to CV power source according to the installation instructions.

Turn the Cobramatic® to the

“ON” position and the Posa Start to the “OFF”

position. Adjust power source to desired voltage for your weld condition. Depress gun trigger and adjust wire feed speed at gun to match voltage set-

ting. If approximate wire feed is not known, it is better to start with excess wire feed rather than too little, in order to prevent a “burn-back”.

Turn the Posa Start switch to the “ON” position. Press torch trigger and, using Run-in Speed Control, adjust wire feed rate to approximately 10% of welding wire speed set at torch.

Strike an arc, and adjust wire feed rate at gun until correct condition is achieved.

CC Posa Start Operation

Attach the Cobramatic® to a CC power source according to the installation instructions.

Insure power supply high frequency switch is in the “OFF” position, and power supply is set to DC reverse polarity.

The power supply contactor should be set to “Remote”

or “Tig” and the

amperage control set to “Panel” or “Standard” depending on power supply. Turn the Cobramatic® power switch to the “ON” position and the Posa Start

switch to the “OFF” position. Adjust power source to desired amperage for your weld condition. Press gun trigger and adjust wire feed speed at gun to match current setting.

If approximate wire feed speed is not known, it is better to start with excess wire feed rather than too little, in order to prevent possible damage to the contact tip.

Turn Posa Start switch to the “ON” position. Press torch trigger and, using Run-in Speed Control, adjust wire feed speed to approximately 10% of welding wire speed set at torch.

Strike an arc; if the wire stubs out, reduce wire feed rate at gun, or increase amperage setting on power source.

NOTE:

Because the Posa Start Run-in Speed always remains a per

centage

of the actual welding wire feed rate, the Posa Start run-in speed

will always slow down or speed up proportional to any

adjustment you now make at the gun. Therefore, if you slow down

the welding wire feed speed, you will have to increase

the Run-in Speed setting.

Cobramatic® Owner’s Manual - page 6

Section C OPTIONAL KITS

The following is a list of Optional Kits available for the Cobramatic® Wire Feeder.

A detailed description of each kit is given later in this section.

P/N Description 005-0316 8ft Interface Cable for Miller 14-Pin, 115VAC

005-0658 25ft Interface Cable for Miller 14-Pin, 115VAC 005-0608 8ft Interface Cable for Lincoln 14-Pin, 115VAC 005-0659 25ft Interface Cable for Lincoln 14-Pin, 115VAC 005-0674 Gas Purge/Trigger Latch Kit 005-0630 8ft Interface Cable for Thermal Arc 19-Pin, 1115VAC 005-0614 8ft Interface Cable for ESAB 19-Pin, 1115VAC

005-0316 8ft Interface Cable for Miller 14-Pin, 115VAC 005-0658 25ft Interface Cable for Miller 14-Pin, 115VAC

When properly connected, these interface cables will supply all the necessary signals and power needed, from most Miller welding power supplies: a Closing Contact signal and 115V

005-0608 8ft Interface Cable for Lincoln 14-Pin, 115VAC 005-0659 25ft Interface Cable for Lincoln 14-Pin, 115VAC

When properly connected, these interface cables will supply all the necessary signals and power needed, from most Lincoln Electric welding power supplies: a Closing Contact signal, Posa-Start Voltage Sensing and 1 input power.

AC input power.

15VAC

005-0630 8ft Interface Cable for Thermal Arc 19-Pin, 1115VAC

When properly connected, these interface cables will supply all the necessary signals and power needed, from most Miller welding power supplies: a Closing Contact signal and 115V

005-0614 8ft Interface Cable for ESAB 19-Pin, 1115VAC

005-0674 Gas Purge/Trigger Latch Kit

The Gas Purge/Trigger Latch Kit is a dual function kit. The kit includes an easy to install interface control PC board, a 24VAC solenoid for pre and post purge control, a modiﬁ switch for activating the Trigger Latch mechanism.

The gas control times have been preset to 0.5 seconds pre-purge and 1.0 seconds post-purge. This offers an optimum amount of inert gas shielding prior to striking the arc and after the arc has been extinguished.

The Trigger Latch mechanism gives the operator the ﬂ exibility of normal trigger operation (pull trigger to weld - release trigger to stop). This also offers the comfort of latched trigger operation (pull trigger once to latch and weld - pull trigger again to unlatch and stop).

ed valve stem for the welding torch and, a front panel

AC input power.

15VAC

Section D Maintenance

Routine Maintenance

Maintenance of the torch will normally consist of a general cleaning of the wire guide system, including tubes, drive rolls, and conduits at regular intervals.

Cobramatic® Owner’s Manual - page 7

Remove spatter build-up from inside of nozzles with a hardwood stick. The only parts on the Cobramatic® system that are subject to normal wear

are the conduit, contact tips, gas cups, front body liners, wire guides, drive and idler rolls. A supply of these parts should be maintained on hand.

If repairs do become necessary, any part can easily be replaced by qualiﬁ ed maintenance personnel.

Your Cobramatic® is designed to provide years of reliable service. Normal wear and component failure may require occasional service.

The number of units in operation and the importance of minimal “down time” will determine to what extent spare parts should be stocked on hand.

Testing the Feeder

Relay K2 Operation

When the torch trigger is pressed, 24VAC is sent to the coil of relay K2. When K2 is energized, AC is sent to the slave motor, spool brake, and the AC contactor. Relay K2 is also responsible for sending 24VAC to the speed control circuit and shorting the torch motor leads together when the trigger is released for the dynamic braking system. K2 also provides the closing contactor signal.

Testing the Input Power Circuits

The AC circuits are protected by fuse F3. If F3 continually blows, disconnect J4 (Brake Solenoid), J7 (Slave Motor) and J5-3 & 4 - if connected (AC Contactor Out.) from the PC board. Replace fuse and re-trigger system. If fuse does not blow, isolate problem by reconnecting J4, J7 and J5-3 & 4 one at a time until the fuse blows.

Testing the Speed Control

NOTE:

The torch should be tested ﬁ rst and the amphenol must be connected to the

Cobramatic® to perform this test.

Place a voltmeter across diode D10

- 24VDC should be observed, as the torch potentiometer varied.

and press torch trigger.

A reading of 0

Cobramatic® Owner’s Manual - page 8

+ 32 hidden pages

MK Products Cobramatic 120VAC User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual