Lincoln Electric K3091-1 User manual

Operator’s Manual
Multi Process Switch
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IM10505 | Issue Date Apr-19
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For use with machines having Code Numbers:
K3091-1
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Thank you for selecting a quality product by Lincoln Electric.
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.
Safety Depends on You - Lincoln Electrc arc welding and cutting equipment is designed and built with safety in
mind. However, your overall safety can be increased by proper installation ... and thoughtful operation on your
part. DO NOT INSTALL, OPERATE OR REPAIR THIS EQUIPMENT WITHOUT READING THIS MANUAL AND THE
SAFETY PRECAUTIONS CONTAINED THROUGHOUT. And, most importantly, think before you act and be careful.
Refer to http://www.lincolnelectric.com/safety
for additional welding safety information.
Refer to http://parts.lincolnelectric.com
for latest service information.
2

SAFETY .................................................................................................................................4
TECHNICAL SPECIFICATIONS........................................................................................................10
NAME PLATE SYMBOL DEFINITIONS.............................................................................................11
GENERAL DESCRIPTION AND OPERATION.....................................................................................11
MOUNTING ...............................................................................................................................12
GENERAL SET-UP.........................................................................................................................12
SET-UP FOR WIRE FEEDER WELDING (AUTOMATIC OR SEMIAUTOMATIC PROCESSES...................13
SET-UP FOR STICK WELDING OR AIR/CARBON ARC WELDING PROCESSES ...................................13
INSTALL AIR DUCT ......................................................................................................................14
WIRING DIAGRAM ........................................................................................................................15
PARTS LIST ..................................................................................PARTS.LINCOLNELECTRIC.COM
CONTENT/DETAILS MAY BE CHANGED OR UPDATED WITHOUT NOTICE. FOR MOST CURRENT
INSTRUCTION MANUALS, GO TO PARTS.LINCOLNELECTRIC.COM
TABLE OF CONTENTS
3

WARNINGS
4
WARNINGS
CALIFORNIA PROPOSITION 65 WARNINGS
WARNING: Breathing diesel engine exhaust exposes you to chemicals
known to the State of California to cause cancer and birth defects, or
other reproductive harm.
• Always start and operate the engine in a
well-ventilated area.
• If in an exposed area, vent the exhaust to the outside.
• Do not modify or tamper with the exhaust system.
• Do not idle the engine except as necessary.
For more information go to
www.P65 warnings.ca.gov/diesel
WARNING: This product, when used for welding or cutting, produces
fumes or gases which contain chemicals known to the State of California
to cause birth defects and, in some cases, cancer. (California Health &
Safety Code § 25249.5 et seq.)
WARNING: Cancer and Reproductive Harm
www.P65warnings.ca.gov
ARC WELDING CAN BE HAZARDOUS. PROTECT YOURSELF AND OTHERS
FROM POSSIBLE SERIOUS INJURY OR DEATH. KEEP CHILDREN AWAY.
PACEMAKER WEARERS SHOULD CONSULT WITH THEIR DOCTOR BEFORE
OPERATING.
Read and understand the following safety highlights. For additional safety information, it is
strongly recommended that you purchase a copy of “Safety in Welding & Cutting - ANSI
Standard Z49.1” from the American Welding Society, P.O. Box 351040, Miami, Florida 33135 or
CSA Standard W117.2-1974. A Free copy of “Arc Welding Safety” booklet E205 is available from
the Lincoln Electric Company, 22801 St. Clair Avenue, Cleveland, Ohio 44117-1199.
BE SURE THAT ALL INSTALLATION, OPERATION, MAINTENANCE AND
REPAIR PROCEDURES ARE PERFORMED ONLY BY QUALIFIED INDIVIDUALS.
FOR ENGINE POWERED EQUIPMENT.
1.a. Turn the engine off before troubleshooting and maintenance work unless the
maintenance work requires it to be running.
1.b. Operate engines in open, well-ventilated areas or vent the engine exhaust fumes
outdoors.
1.c. Do not add the fuel near an open flame welding arc or when the engine is running.
Stop the engine and allow it to cool before refueling to prevent spilled fuel from
vaporizing on contact with hot engine parts and igniting. Do not spill fuel when
filling tank. If fuel is spilled, wipe it up and do not start engine until fumes have
been eliminated.
1.d. Keep all equipment safety guards, covers
and devices in position and in good repair. Keep hands, hair, clothing and tools away
from V-belts, gears, fans and all other
moving parts when starting, operating or repairing equipment.
1.e. In some cases it may be necessary to remove safety guards to perform required
maintenance. Remove guards only when necessary and replace them when the
maintenance requiring their removal is complete. Always use the greatest care when
working near moving parts.
1.f. Do not put your hands near the engine fan. Do not attempt to override the governor
or idler by pushing on the throttle control rods while the engine is running.
1.g. To prevent accidentally starting gasoline engines while turning the engine or welding
generator during maintenance work, disconnect the spark plug wires, distributor cap
or magneto wire as appropriate.
1.h. To avoid scalding, do not remove the radiator pressure cap when the engine is hot.
ELECTRIC AND MAGNETIC FIELDS MAY BE
DANGEROUS
2.a. Electric current flowing through any conductor causes localized Electric and
Magnetic Fields (EMF). Welding current creates EMF fields around welding cables
and welding machines
2.b. EMF fields may interfere with some pacemakers, and
welders having a pacemaker should consult their physician before welding.
2.c. Exposure to EMF fields in welding may have other health effects which are now not known.
2.d. All welders should use the following procedures in order to minimize exposure to EMF fields from
the welding circuit:
2.d.1. Route the electrode and work cables together - Secure them with tape when possible.
2.d.2. Never coil the electrode lead around your body.
2.d.3. Do not place your body between the electrode and work cables. If the electrode cable is
on your right side, the work cable should also be on your right side.
2.d.4. Connect the work cable to the workpiece as close as possible to the area being welded.
2.d.5. Do not work next to welding power source.

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

WARNINGS
6
WELDING AND CUTTING SPARKS CAN
CAUSE FIRE OR EXPLOSION.
6.a. Remove fire hazards from the welding area. If this is not possible, cover them to
prevent the welding sparks from starting a fire. Remember that welding sparks
and hot materials from welding can easily go through small cracks and
openings to adjacent areas. Avoid welding near hydraulic lines. Have a fire
extinguisher readily available.
6.b. Where compressed gases are to be used at the job site, special precautions should be used to
prevent hazardous situations. Refer to “Safety in Welding and Cutting” (ANSI Standard Z49.1) and
the operating information for the equipment being used.
6.c. When not welding, make certain no part of the electrode circuit is touching the work or ground.
Accidental contact can cause overheating and create a fire hazard.
6.d. Do not heat, cut or weld tanks, drums or containers until the proper steps have been taken to
insure that such procedures
will not cause flammable or toxic vapors from substances inside. They can cause an explosion
even though they have been “cleaned”. For information, purchase “Recommended Safe Practices
for the Preparation for Welding and Cutting of Containers and Piping That Have Held Hazardous
Substances”, AWS F4.1 from the American Welding Society
(see address above).
6.e. Vent hollow castings or containers before heating, cutting or welding. They may explode.
6.f. Sparks and spatter are thrown from the welding arc. Wear oil free protective garments such as
leather gloves, heavy shirt, cuffless trousers, high shoes and a cap over your hair. Wear ear plugs
when welding out of position or in confined places. Always wear safety glasses with side shields
when in a welding area.
6.g. Connect the work cable to the work as close to the welding area as practical. Work cables
connected to the building framework or other locations away from the welding area increase the
possibility of the welding current passing through lifting chains, crane cables or other alternate
circuits. This can create fire hazards or overheat lifting chains or cables until they fail.
6.h. Also see item 1.c.
6.I. Read and follow NFPA 51B “Standard for Fire Prevention During Welding, Cutting and Other Hot
Work”, available from NFPA, 1 Batterymarch Park, PO box 9101, Quincy, MA 022690-9101.
6.j. Do not use a welding power source for pipe thawing.
CYLINDER MAY EXPLODE IF DAMAGED.
7.a. Use only compressed gas cylinders containing the correct shielding gas for the
process used and properly operating regulators designed for the gas and
pressure used. All hoses, fittings, etc. should be suitable for the application and
maintained in good condition.
7.b. Always keep cylinders in an upright position securely chained to an under-
carriage or fixed support.
7.c. Cylinders should be located:
• Away from areas where they may be struck or subjected to physical damage.
• A safe distance from arc welding or cutting operations and any other source of heat,
sparks, or flame.
7.d. Never allow the electrode, electrode holder or any other electrically “hot” parts to touch a cylinder.
7.e. Keep your head and face away from the cylinder valve outlet when opening the cylinder valve.
7.f. Valve protection caps should always be in place and hand tight except when the cylinder is in use
or connected for use.
7.g. Read and follow the instructions on compressed gas cylinders, associated equipment, and CGA
publication P-l, “Precautions for Safe Handling of Compressed Gases in Cylinders,” available from
the Compressed Gas Association, 14501 George Carter Way Chantilly, VA 20151.
FOR ELECTRICALLY POWERED
EQUIPMENT.
8.a. Turn off input power using the disconnect switch at the fuse box before working
on
the equipment.
8.b. Install equipment in accordance with the U.S. National Electrical Code, all local
codes and the manufacturer’s recommendations.
8.c. Ground the equipment in accordance with the U.S. National Electrical Code and the
manufacturer’s recommendations.

WARNINGS
7

WARNINGS
8
ELECTROMAGNETIC COMPATIBILITY (EMC)
ConformanCe
Products displaying the CE mark are in conformity with European Community Council Directive. It was
manufactured in conformity with a national standard that implements a harmonized standard: EN 60974-10
Electromagnetic Compatibility (EMC) Product Standard for Arc Welding Equipment. It is for use with other
Lincoln Electric equipment. It is designed for industrial and professional use.
IntroduCtIon
All electrical equipment generates small amounts of electromagnetic emission. Electrical emission may be
transmitted through power lines or radiated through space, similar to a radio transmitter. When emissions are
received by other equipment, electrical interference may result. Electrical emissions may affect many kinds of
electrical equipment; other nearby welding equipment, radio and TV reception, numerical controlled
machines, telephone systems, computers, etc.
WARNING: This Class A equipment is not intended for use in residential locations where the electrical power
is provided by the public low-voltage supply system. There may be potential difficulties in ensuring electro-
magnetic compatibility in those locations, due to conducted as well as radiated disturbances.
INSTALLATION AND USE
The user is responsible for installing and using the welding equipment according to the manufacturer’s
instructions.
If electromagnetic disturbances are detected then it shall be the responsibility of the user of the welding
equipment to resolve the situation with the technical assistance of the manufacturer. In some cases this
remedial action may be as simple as earthing (grounding) the welding circuit, see Note. In other cases it could
involve constructing an electromagnetic screen enclosing the power source and the work complete with
associated input filters. In all cases electromagnetic disturbances must be reduced to the point where they
are no longer troublesome.
NOTE: The welding circuit may or may not be earthed for safety reasons. Follow your local and national
standards for installation and use. Changing the earthing arrangements should only be authorized by a person
who is competent to assess whether the changes will increase the risk of injury, e.g., by allowing parallel
welding current return paths which may damage the earth circuits of other equipment.
ASSESSMENT OF AREA
Before installing welding equipment the user shall make an assessment of potential electromagnetic
problems in the surrounding area. The following shall be taken into account:
a) other supply cables, control cables, signaling and telephone cables; above, below and adjacent to the
welding equipment;
b) radio and television transmitters and receivers;
c) computer and other control equipment;
d) safety critical equipment, e.g., guarding of industrial equipment;
e) the health of the people around, e.g., the use of pacemakers and hearing aids;
f) equipment used for calibration or measurement;
g) the immunity of other equipment in the environment. The user shall ensure that other equipment being
used in the environment is compatible. This may require additional protection measures;
h) the time of day that welding or other activities are to be carried out.
The size of the surrounding area to be considered will depend on the structure of the building and other
activities that are taking place. The surrounding area may extend beyond the boundaries
of the premises.
METHODS OF REDUCING EMISSIONS
Public Supply System
Welding equipment should be connected to the public supply system according to the manufacturer’s recom-
mendations. If interference occurs, it may be necessary to take additional precautions such as filtering of the
system. Consideration should be given to shielding the supply cable of permanently installed welding
equipment, in metallic conduit or equivalent. Shielding should be electrically continuous throughout its length.
The shielding should be
connected to the welding power source so that good electrical contact is maintained between the conduit and
the welding power source enclosure.
maintenanceof theWelding equipment
The welding equipment should be routinely maintained according to the manufacturer’s recommendations. All
access and service doors and covers should be closed and properly fastened when the welding equipment is
in operation. The welding equipment should not be modified in any way except for those changes and
adjustments covered in the manufacturer’s instructions. In particular, the spark gaps of arc striking and
stabilizing devices should be adjusted and maintained according to the manufacturer’s recommendations.
Welding Cables
The welding cables should be kept as short as possible and should be positioned close together, running at or
close to the floor level.
equipotential Bonding
Bonding of all metallic components in the welding installation and adjacent to it should be considered.
However, metallic components bonded to the work piece will increase the risk that the operator could receive
a shock by touching these metallic components and the electrode at the same time. The operator should be
insulated from all such bonded metallic components.
earthing of theWorkpiece
Where the workpiece is not bonded to earth for electrical safety, nor connected to earth because of its size
and position, e.g., ship’s hull or building steelwork, a connection bonding the workpiece to earth may reduce
emissions in some, but not all instances. Care should be taken to prevent the earthing of the workpiece
increasing the risk of injury to users, or damage to other electrical equipment. Where necessary, the
connection of the workpiece to earth should be made by a direct connection to the workpiece, but in some
countries where direct connection is not permitted, the bonding should be achieved by suitable capacitance,
selected according to national regulations.
Screening and Shielding
Selective screening and shielding of other cables and equipment in the surrounding area may alleviate
problems of interference. Screening of the entire welding installation may be considered for special appli-
cations. 1
1 Portions of the preceding text are contained in EN 60974-10 “Electromagnetic Compatibility (EMC) product standard for arc
welding equipment.”

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

MULTI-PROCESS SWITCH
10
Multi-Process Switch - K3091-1
Amperage and duty cycle are increased when the Multi-Process Switch is con-
nected to a FLEXTEC™ 650 using the supplied air duct:
OUTPUT AND DUTY CYCLE RATINGS OF
THE MULTI-PROCESS SWITCH:
Duty Cycle Volts Amps
60 % 38 450
100 % 36 400
AMPERAGE AND DUTY CYCLE - FLEXTEC™ 650 WITH AIR DUCT:
Duty Cycle Volts Amps
60 % 44 700
100 % 44 600
WEIGHT
57 lbs (25.86 kg)
TECHNICAL SPECIFICATIONS

INSTALLATION
MULTI-PROCESS SWITCH
11
INSTALLATION
SAFETY PRECAUTIONS
READ AND UNDERSTAND ENTIRE SECTION BEFORE OPERATING MACHINE.
ELECTRIC SHOCK can kill.
• Turn the input power OFF at the disconnect switch or fuse box
before working on this equipment. Turn off the input power to any
other equipment connected to the welding system at the
disconnect switch or fuse box before working on the equipment.
• Do not touch electrically hot parts.
• Only qualified personnel should install, use pr service this equipment.
name PLate SYmBoL defInItIonS
1. NEGATIVE POLARITY
2. POSITIVE POLARITY
3. AUTOMATIC OR SEMIAUTOMATIC WIRE
PROCESS
4. STICK OR AIR/CARBON ARC
5. DO NOT SWITCH UNDER LOAD
6. INPUT CONNECTION
generaL deSCrIPtIon and oPeratIon
The Multi-Process Switch provides the ability to select between “Stick or Air/Carbon Arc” and
“Automatic or Semiautomatic” processes, and a change of the “Automatic or Semiautomatic
polarity without changing any electrical connections.
The Multi-Process Switch has two sets of output terminals. The wire feeder unit cables connect
to the set of terminals on the left side of the Multi-Process Switch, and the stick or air/carbon
arc cables connect to the set of terminals on the right side (facing the front of the machine). The
output terminals are protected against accidental contact by hinged covers.
When the Multi-Process Switch is in the “Stick or Air/Carbon Arc” position, only those terminals
are energized. The wire feeder nozzle or gun and electrode are not electrically “hot” when in
this mode.
• While in the “Automatic or Semiautomatic” mode, the electrode polarity can be switched.
• While in the “Stick or Air/Carbon Arc” mode, the electrode cables must be reversed to
change polarity.
Do not switch the selector switch while welding.
WARNING
1 6 2 34
5
FIGURE A.1

INSTALLATIONMULTI-PROCESS SWITCH
12
mountIng See Figure A.2
Mount the Multi-Process Switch directly to the bottom of a compatible FLEXTEC™ series power
source utilizing the quick lock mechanism shown in Figure A.2. Mounting the Flextec to the
Multi-Process switch requires the use of a Foot Kit on the FLEXTEC™ power sources. This kit
may not be a part of some Flextec models and may need to be installed separately.
FIGURE A.2
generaL Set-uP See Figure A.3
1. Welding cables must be of proper capacity for the current and duty cycle of immediate and
future applications. See Instruction Manual of the power source for output cable size
guidelines.
2. Connect (+) lead of the Multi-Process Switch to the corresponding positive (+) terminal of
the power source.
3. Connect (-) lead of the Multi-Process Switch to the corresponding negative (-) terminal of
the power source.
FIGURE A.3
Foot
Mounting Kit
not shown

INSTALLATIONMULTI-PROCESS SWITCH
13
Set-uP for WIre feeder WeLdIng(automatIC or SemIautomatIC
ProCeSSeS See Figure A.4
1. Move the switch on the Multi-Process unit (Item A) to the left to set to either positive (+) or
negative (-) polarity. See Figure A.4. DO NOT SWITCH THE SELECTOR SWITCH WHILE
WELDING.
There is no need to change the welding cables for a different polarity (i.e. solid wire (+) and
Fluxcore/Innershield (-)).
2. The (+) and (-) setting will energize the Multi-Process Switch terminals on the left side and
give (+) and (-) polarity depending on which setting is chosen. The output terminals on the
right side of the Multi-Process Switch will not be electrically “hot”.
3. Connect the Electrode cable from the Wire Feeder to the electrode terminal of the Multi-
Process Switch. See Figure A.4.
4. Connect the work cable to the work terminal on the left side of the Multi-Process Switch.
The other side of the work cable will be attached to the workpiece. See Figure A.4.
5. Select the desired constant voltage mode on the power source.
6. Ensure that the control cable from the power source to the wire feeder is correctly
connected.
7. Turn the power source on.
FIGURE A.4
Set-uP for StICK WeLdIngor aIr/CarBon arC WeLdIngProCeSSeS
See Figure A.5
1. Move the switch on the Multi-Process unit to the right to set to “Stick or Air/Carbon Arc”
setting. See Figure A.5 (Item A). DO NOT SWITCH THE SELECTOR SWITCH WHILE WELDING.
2. Ensure that the power source is configured for SMAW or CAG (if so equipped).
3. Connect the electrode and work cables to the output terminals of the Multi-Process Switch
(located on the right side of the Multi-Process unit). See Figure A.5.
4. Select the desired weld mode on the power supply.
5. Turn on the power source and activate the welding terminals on the power source.
To change the electrode polarity, the weld cables connected to the output terminals (located
on the right side of the unit) must be reversed.
FIGURE A.5
A
A
Work
Positive
Electrode
Negative

INSTALLATIONMULTI-PROCESS SWITCH
14
FOR INSTANCES WHERE THE WORK TERMINAL (LEFT SIDE) AND THE NEGATIVE TERMINAL
(RIGHT SIDE) ARE TIED TOGETHER: If using both a stick and wire process, it may be desirable to
only run one single cable to the work piece. In this case, the NEGATIVE terminal from the right
side and WORK terminal from the left side can be jumpered together with a short piece of
welding cable (Item A). The welding cable can be passed through the access holes in the back
of the Multi-Process Switch to have a clean set-up. See Figure A.6.
Figure A.6
InStaLLatIon of aIr duCt on fLeXteC™ 650X for InCreaSed ratIngS
Figure A.7
A
Work Not Provided
Lip of Air Duct to be
tucked under top
louver before
securing
Air Duct

DIAGRAMS
MULTI-PROCESS SWITCH
15
left side/ wire welding side
Multi Process
Switch Front
Multi-process switch
rear
Right side / Stick / Carbon Arc gouge side

CuStomer aSSIStanCe PoLICY
The business of The Lincoln Electric Company is manufacturing and selling high quality welding
equipment, consumables, and cutting equipment. Our challenge is to meet the needs of our
customers and to exceed their expectations. On occasion, purchasers may ask Lincoln Electric for
advice or information about their use of our products. We respond to our customers based on the
best information in our possession at that time. Lincoln Electric is not in a position to warrant or
guarantee such advice, and assumes no liability, with respect to such information or advice. We
expressly disclaim any warranty of any kind, including any warranty of fitness for any customer’s
particular purpose, with respect to such information or advice. As a matter of practical consideration,
we also cannot assume any responsibility for updating or correcting any such information or advice
once it has been given, nor does the provision of information or advice create, expand or alter any
warranty with respect to the sale of our products.
Lincoln Electric is a responsive manufacturer, but the selection and use of specific products sold by
Lincoln Electric is solely within the control of, and remains the sole responsibility of the customer.
Many variables beyond the control of Lincoln Electric affect the results obtained in applying these
types of fabrication methods and service requirements.
Subject to Change – This information is accurate to the best of our knowledge at the time of printing.
Please refer to www.lincolnelectric.com for any updated information.