Cornwell Tools MMWMP242DVI User manual

MMWMP242DVI
OWNER’S MANUAL
3/2019
WARNING:
Read carefully and understand all ASSEMBLY AND OPERATION
INSTRUCTIONS before operating. Failure to follow the safety rules and other
basic safety precautions may result in serious personal injury.

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EFFECTIVE AUGUST 7, 2015
LIMITED WARRANTY
This warranty applies to the original purchaser and is subject to the terms and conditions listed below. This Limited Warranty is for
new equipment sold after the above date, providing coverage for defects in material and workmanship at the time it is shipped from
the factory.
Limited to the warranty periods below, Cornwell Quality Tools will repair or replace the item under warranty that fails due to defects
in material and workmanship. Cornwell Quality Tools must be notified within 30 days of the failure, so as to provide instructions on
how to proceed with the repair of your welder and warranty claim processing. Warranty period begins at the time the welder is
purchased from andAuthorized Cornwell Distributor. Keep your receipt as proof of purchase.
Warranty Periods
Limited Warranty is divided into three categories. No Warranty, 1 year and 3 year.
No Warranty
Normal wear items, MIG gun parts (contact tips, nozzle, contact tip adapter, MIG gun liner), drive roll, electrode holder, ground
clamps, Plasma torch parts (nozzle, electrode, diffuser, cover) are considered consumable items and are not covered under
warranty.
1 year
Parts and Labor on MIG gun parts (except those listed under normal wear items), cables, regulator, and plasma torch (except those
listed under normal wear items).Any shipping related to warranty repair is the responsibility of the customer.
1 year/3 year
Please see your product information to determine if your product has a 1 year or 3-year warranty. This warranty covers parts and
Labor on items such as: transformer, reactor, rectifier, solenoid valve, PC Board, switches, controls, gas valve, drive motor, drive
system other than drive roll and any other component that requires the removal of the sheet metal to access. Any shipping related
to warranty repair is the responsibility of the customer.
Voiding Warranty
Warranty does not apply to: Shipping Damage, Misuse and abuse of the unit, alteration of the unit in any way.
Warranty Claim
This is a parts and labor warranty. Contact your Cornwell distributor you purchased it from. Retain your receipt in the case a
warranty claim is needed. No warranty will be provided without the original receipt from an authorized Cornwell Distributor. To make
a warranty claim, contact your Cornwell Distributor. That Cornwell Distributor will contact the customer service department for
warranty instructions.

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GENERAL SAFETY RULES
WARNING: Read and understand all instructions. Failure to follow all instructions listed
below may result in serious injury.
CAUTION: Do not allow persons to operate or assemble this MMWMP242DVI until they
have read this manual and have developed a thorough understanding of how the
MMWMP242DVI works.
WARNING: The warnings, cautions, and instructions discussed in this instruction
manual cannot cover all possible conditions or situations that could occur. It must be
understood by the operator that common sense and caution are factors which cannot be built into
this product but must be supplied by the operator.
WARNING
Breathing welding fumes exposes you to chemicals, including chromium (hexavalent compounds),
known to the State of California to cause cancer and birth defects or other reproductive harm.
*Always weld in a well-ventilated area. * If in an enclosed area, vent the exhaust to the outside. For
more information go to www.P65warings.ca.gov
WARNING
This product can expose you to chemicals including Lead, which is known to the State of California
to cause cancer and birth defects or other reproductive harm. For more information go to
www.P65warings.ca.gov
SAVE THESE INSTRUCTIONS
IMPORTANT SAFETY CONSIDERATIONS
1.1 Your Welding Environment
-Keep the environment you will be welding in free from flammable materials.
-Always keep a fire extinguisher accessible to your welding environment.
-Always have a qualified person install and operate this equipment.
-Make sure the area is clean, dry and ventilated. Do not operate the welder in humid, wet or poorly
ventilated areas.
-Always have your welder maintained by a qualified technician in accordance with local, state and
national codes.
-Always be aware of your work environment. Be sure to keep other people, especially children,
away from you while welding.
-Keep harmful arc rays shielded from the view of others.
-Mount the welder on a secure bench or cart that will keep the welder secure and prevent it from
tipping over or falling.
1.2 Your Welder’s Condition
-Check ground cable, power cord and welding cable to be sure the insulation is not damaged.

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Always replace or repair damaged components before using the welder.
-Check all components to ensure they are clean and in good operating condition before use.
1.3 Use of Your Welder
Do not operate the welder if the output cable, electrode, torch, wire or wire feed system is wet. Do
not immerse them in water. These components and the welder must be completely dry before
attempting to use them.
-Follow the instructions in this manual.
-Keep welder in the off position when not in use.
-Connect ground lead as close to the area being welded as possible to ensure a good ground.
-Do not allow any body part to come in contact with the welding wire if you are in contact with the
material being welded, ground or electrode from another welder.
-Do not weld if you are in an awkward position. Always have a secure stance while welding to
prevent accidents. Wear a safety harness if working above ground.
-Do not drape cables over or around your body.
-Wear a full coverage helmet with appropriate shade (see ANSI Z87.1 safety standard) and safety
glasses while welding.
-Wear proper gloves and protective clothing to prevent your skin from being exposed to hot metals,
UV and IR rays.
-Do not overuse or overheat your welder. Allow proper cooling time between duty cycles.
-Keep hands and fingers away from moving parts and stay away from the drive rolls.
-Do not point torch at any body part of yourself or anyone else.
-Always use this welder in the rated duty cycle to prevent excessive heat and failure.
1.4 Specific Areas of Danger, Caution or Warning
Electrical Shock
Electric arc welders can produce a shock that can cause injury or death. Touching
electrically live parts can cause fatal shocks and severe burns. While welding, all metal
components connected to the wire are electrically hot. Poor ground connections are a hazard, so
secure the ground lead before welding.
-Wear dry protective apparel: coat, shirt, gloves and insulated footwear.
-Insulate yourself from the work piece.Avoid contacting the work piece or ground.
- Do not attempt to repair or maintain the welder while the power is on.
-Inspect all cables and cords for any exposed wire and replace immediately if found.
-Use only recommended replacement cables and cords.
-Always attach ground clamp to the work piece or worktable as close to the weld area as possible.
-Do not touch the welding wire and the ground or grounded work piece at the same time.
-Do not use a welder to thaw frozen pipes.
Fumes and Gases
-Fumes emitted from the welding process displace clean air and can result in injury or
death.
-Do not breathe in fumes emitted by the welding process. Make sure your breathing air is clean and
safe.
-Work only in a well-ventilated area or use a ventilation device to remove welding fumes from the

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environment where you will be working.
-Do not weld on coated materials (galvanized, cadmium plated or containing zinc, mercury or
barium). They will emit harmful fumes that are dangerous to breathe. If necessary, use a ventilator,
respirator with air supply or remove the coating from the material in the weld area.
-The fumes emitted from some metals when heated are extremely toxic. Refer to the material safety
data sheet for the manufacturer’s instructions.
-Do not weld near materials that will emit toxic fumes when heated. Vapors from cleaners, sprays
and degreasers can be highly toxic when heated.
UV and IR Arc Rays
The welding arc produces ultraviolet (UV) and infrared (IR) rays that can cause injury to
your eyes and skin. Do not look at the welding arc without proper eye protection.
-Always use a helmet that covers your full face from the neck to top of head and to the back of each
ear.
-Use a lens that meets ANSI standards and safety glasses. For welders under 160 Amps output,
use a shade 10 lens; for above 160 Amps, use a shade 12. Refer to the ANSI standard Z87.1 for
more information.
-Cover all bare skin areas exposed to the arc with protective clothing and shoes. Flame-retardant
cloth or leather shirts, coats, pants or coveralls are available for protection.
-Use screens or other barriers to protect other people from the arc rays emitted from your welding.
-Warn people in your welding area when you are going to strike an arc so they can protect
themselves.
Fire Hazards
Do not weld on containers or pipes that contain or have had flammable, gaseous or liquid
combustibles in them. Welding creates sparks and heat that can ignite flammable and
explosive materials.
-Do not operate any electric arc welder in areas where flammable or explosive materials are
present.
-Remove all flammable materials within 35 feet of the welding arc. If removal is not possible, tightly
cover them with fireproof covers.
-Take precautions to ensure that flying sparks do not cause fires or explosions in hidden areas,
cracks or areas you cannot see.
-Keep a fire extinguisher close in the case of fire.
-Wear garments that are oil-free with no pockets or cuffs that will collect sparks.
-Do not have on your person any items that are combustible, such as lighters or matches.
-Keep work lead connected as close to the weld area as possible to prevent any unknown,
unintended paths of electrical current from causing electrical shock and fire hazards.
-To prevent any unintended arcs, cut wire back to ¼" stick out after welding.
Hot Materials
Welded materials are hot and can cause severe burns if handled improperly.
-Do not touch welded materials with bare hands.
-Do not touch torch nozzle after welding until it has had time to cool down.
Sparks/Flying Debris
Welding creates hot sparks that can cause injury. Chipping slag off welds creates flying

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debris.
-Always wear protective apparel: ANSI-approved safety glasses or shield, welder’s hat and ear
plugs to keep sparks out of ears and hair.
Electromagnetic Field
-Electromagnetic fields can interfere with various electrical and electronic devices such as
pacemakers.
-Consult your doctor before using any electric arc welder or cutting device
-Keep people with pacemakers away from your welding area when welding.
-Do not wrap cable around your body while welding.
-Wrap MIG gun and ground cable together whenever possible.
-Keep MIG gun and ground cables on the same side of your body.
Shielding Gas Cylinders Can Explode
High pressure cylinders can explode if damaged, so treat them carefully.
-Never expose cylinders to high heat, sparks, open flames, mechanical shocks or arcs.
-Do not touch cylinder with MIG gun.
-Do not weld on the cylinder
-Always secure cylinder upright to a cart or stationary object.
-Keep cylinders away from welding or electrical circuits.
-Use the proper regulators, gas hose and fittings for the specific application.
-Do not look into the valve when opening it.
-Use protective cylinder cap whenever possible
1.5 Proper Care, Maintenance and Repair
-Always have power disconnected when working on internal components.
- Do not touch or handle PC board without being properly grounded with a wrist strap. Put PC board
in static proof bag to move or ship.
-Do not put hands or fingers near moving parts such as drive rolls of fan
MMWMP242DVI USE AND CARE
•Do not modify this unit in any way. Unauthorized modification may impair the function and/or
safety and could affect the life of the equipment. There are specific applications for which this
unit was designed.
•Always check for damaged or worn out parts before using this unit. Broken parts will affect
the operation. Replace or repair damaged or worn parts immediately.
•Store idle. When this unit is not in use, store it in a secure place out of the reach of children.
Inspect it for good working condition prior to storage and before re-use.

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TECHNICAL SPECIFICATIONS
Item
Description
Power Supply
120V, 20A, 50/60 Hz, Single Phase
230V, 36A, 50/60 Hz, Single Phase
No-Load Voltage
69V DC
Output Range - MIG
40 to 90A DC with 120V Input Power
40 to 200A DC with 230V Input Power
Output Range –STICK
10 to 70A DC with 120V Input Power
10 to 180A DC with 230V Input Power
Output Range –TIG
10 to 90A DC with 120V Input Power
10 to 180A DC with 230V Input Power
Duty Cycle-MIG
40% @ 90A with 120V Input Power
20% @ 200A with 230V Input Power
Duty Cycle-STICK
40% @ 70A with 120V Input Power
20% @ 180A with 230V Input Power
Duty Cycle-TIG
40% @ 90A with 120V Input Power
20% @ 180A with 230V Input Power
Suggested Wire
Steel, Stainless Steel, Aluminum (With Optional Spool Gun)
Suggested Wire Diameter
.023, .030; .035
Suggested Electrodes
E6013, E7014, E7018, Stainless Steel
Electrode Diameter
1/16 inch to 5/32 inch
Dimensions
21” x 9 ½” x 16 ¼”
Weight
35 lbs.
DESCRIPTION
The Cornwell MMWMP242DVI is an inverter-powered, dual voltage, wire feed welder for flux core and
MIG welding plus a DC stick welder. It features a Synergic LCD control that allows the operator to select
process and weld settings. It comes complete with a regulator and gas hose for easy connection for MIG
welding plus a weld cable and electrode holder for DC stick welding. Directly connect this unit to a 230V
NEMA 6-50R receptacle or attach the supplied 120V adapter cord to operate off of 120V power. It is
designed to weld materials as thin as 24 gauge all the way up to 3/8" in a single pass. The Spool Gun
(B model optional purchase item MMWEZFSG2) is capable of welding aluminum with 4" spools of
aluminum wire. This unit can also perform lift start DC TIG welding (B model optional purchase item
MMWACTT2V) on steel and stainless-steel materials. Argon shielding gas and a TIG filler rod would also
be required for TIG welding.
This unit is intended to be used on a 50-amp 230V AC circuit or 120V, 20A AC circuit, without the use of
an extension cord. If an extension cord is necessary for your application, use the appropriate size and
length of extension cord that will handle 50 amps the entire length of the extension. We highly
recommend talking with a qualified electrician for cord size recommendations. This unit is supplied with a
NEMA Class 6-50P plug and will require a NEMA Class 6-50R receptacle. Do not remove the power
plug. Use the supplied 120V adapter when running off 120V power.
Inverter-based welding provides a smoother arc, increases efficiency, and provides better control than
non-inverter welding machines.

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LCD SYNERGIC CONTROL
The LCD Synergic Control sets and operates the welder based on selections the operator makes in
weld process and material selections.
MIG TORCH
The welding wire is driven through the welding cable and torch to the work piece. It is attached to the
drive system. The trigger activates the drive motor.
TIG TORCH (OPTIONAL WITH MMWMP242DVIB)
The TIG torch transfers welding power from the welding power source to the tungsten for the
purpose of TIG welding. It also delivers the shielding gas from the welding power source to the
SPOOL GUN (OPTIONAL WITH MMWMP242DVIB)
The Spool Gun is typically used for welding aluminum. The soft aluminum wire has a hard time feeding
consistently in the standard MIG torch. Load 4in. spools of aluminum wire in the spool gun for easy and
consistent feeding of aluminum wire.
ELECTRODE HOLDER AND CABLE
The Electrode Holder holds the stick welding electrode. The cable most often connects to the Positive (+)
weld output connection for stick welding.
Welding
Voltage Control
MIG Torch and
Consumables
Electrode Holder
and Cable
Inert Gas
Hose
Ground Cable
and Clamp
Inert Gas
Regulator
TIG Torch and
Consumables
(MMWACTT2V)
Spool Gun
(MMWEZFSG2)
Multi-Function
Adjustment/Selector
Knob
LCD Screen
120V Adapter
Cord

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POWER CORD AND PLUG
Plug this unit into a 230V, 50-amp circuit breaker power supply when operating on 230V. If running
on 120V power using the supplied 120V power cord adapter, plug this unit into a 120V, 20-amp
circuit breaker power supply.
INERT GAS REGULATOR AND HOSE
The Inert Gas Regulator installs on the shielding gas cylinder for MIG welding with solid wires. The
regulator controls the compressed gas and allows you to adjust the flow rate of the gas. The gas hose
connects to the regulator/flow gauge and delivers the shielding gas from the shielding gas bottle to the
welder.
MULTI-FUNCTION ADJUSTMENT/SELECTOR KNOB
The Multi-Function Adjustment/Selector Knob is used by the operator to interact with the LCD Synergic
Control. It is used for the selection and adjustment of welding processes, materials, and selections within
the LCD Synergic Control screen.
WELDING VOLTAGE CONTROL
The voltage control allows the operator to make manual voltage adjustments to the LCD Synergic
programming.
GROUND CABLE AND CLAMP
The ground cable and clamp are attached to the work piece to complete the circuit allowing the flow of
current needed to weld.
INSTALLATION
Electrical Shock
•High voltage danger from power source! Consult a qualified electrician for proper
installation of receptacle. This welder must be grounded while in use to protect the
operator from electrical shock.
•Do not remove grounding prong or alter the plug in any way. Use only the supplied
adapter between the plasma cutter's power cord and the power source receptacle. Make
sure the POWER switch is OFF when connecting your welder’s power cord directly to a
properly grounded 230 VAC, 60 HZ, Single Phase, 50 Amp input power supply. Or, when
using the supplied 120V adapter, connect the 120V Adapter to a properly grounded 120V,
20 Amp input power supply.
1. POWER REQUIREMENT 230V - AC single phase 230V (220-240V) 50/60 HZ fused with a
50-amp time delayed fuse or circuit breaker is required. DO NOT OPERATE THIS UNIT if the
ACTUAL power source voltage is less than 215 volts AC or greater than 240 volts AC.
2. POWER REQUIREMENT 120V - AC single phase 120V (110-130V) 50/60 HZ fused with a
20-amp time delayed fuse or circuit breaker is required. DO NOT OPERATE THIS UNIT if the
ACTUAL power source voltage is less than 110 volts AC or greater than 130 volts AC.
2.1 When connecting this unit to 120V power, connect the 120V adapter cord to the
power cord pigtail that is attached to the machine.
3. EXTENSION CORD - We do not recommend an extension cord because of the voltage drop
produced. This drop, in voltage can affect the performance of the welder. If you need to use an
extension cord, check with a qualified electrician and your local electrical codes for your specific
area.

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4. INSTALL THE WIRE ROLLER - The wire roller has been factory installed. However, check to
make certain the correct wire groove is in place to accommodate the size of wire you are using.
Open the wire feed compartment. Adjust the drive roller according to the following steps. See
Figure 2 about the wire feeder structure:
Figure 2
4.1 Open the door to the welder drive compartment.
4.2 Remove the drive tension by loosening the Drive Tension Adjuster (1) and moving the
Drive Tension Adjustor away from the Drive Tension Arm (2). Lift the Drive Tension
Arm away from the Drive Roller (3).
4.3 If there is wire already installed in the welder, roll it back onto the wire spool by
hand-turning the spool clockwise. Be careful not to let all the wire come out of the rear
end of the inlet guide tube. Hold onto it or the wire spool will unspool itself. Put the
end of the wire into the hole on the outside edge of the wire spool and bend it over to
hold the wire in place. Remove the spool of wire from the drive compartment of the
welder.
4.4 Remove the drive roller by turning the drive roll knob (3) counterclockwise. Carefully
slide the drive roll assembly off of the drive shaft. This drive roll assembly consists of
three pieces. The outer drive roll, inner drive roll, and a key. Be careful not to
misplace the key.
4.5 Based on the wire diameter, select the correct groove. When installing the drive roller,
the number stamped on the drive roller for the wire size you are using should be
facing you. Push the Drive Roller onto the Drive Roller Shaft.
4.6 Reinstall the Drive Roller knob and tighten clockwise.
4.7 Close the door to the welder drive compartment.
Electrical Shock
•Electric shock can kill! Always turn the POWER switch OFF and unplug the power cord
from the AC power source before installing wire.
NOTE: Before installing, make sure that you have removed any old wire from the torch
assembly. This will help to prevent the possibility of the wire jamming inside the gun liner.
1
2
3

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NOTE: Be very careful when removing the welding nozzle. The contact tip on this welder is live
whenever the torch trigger is pulled. Make certain power is turned OFF.
5. INSTALL THE WIRE - We recommend the usage of .023, .030 & .035 MIG wire, or .030 and
.035 flux core wire, on this unit.
5.1 Select welding wire - Both four-inch or eight-inch wire spools of .023, .030, or .035
wire can be used on this welder.
NOTE: Burn-through can occur if you attempt to weld mild or stainless steel thinner than 24
gauge.
NOTE: Remove all rusted wire from your wire spool. If the whole spool is rusty, discard it.
5.2 Installing the wire.
5.2.1 Remove the nozzle and contact tip from the end of the torch assembly.
See Figure 3.
5.2.2 Make sure the proper groove on the drive roller is in place for the wire
installed. If not, change the drive roller as described in INSTALL THE
WIRE ROLLER above.
5.2.3 Remove the packaging from the spool of wire and then identify the
leading end of the wire secured on the edge of the spool. DO NOT
UNHOOK IT AT THIS TIME.
Figure 3
5.2.4 Place the spool on the spool hub so the wire will pull off the bottom of
the spool. The welding wire should always come off the bottom of the
spool into the drive mechanism (Figure 4).
MIG
Nozzle
Flux Core
Nozzle
Contact
Tip

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Figure 4
5.2.5 The welder can use either 4 inch or 8 inch spools. See Figure 5 for
additional reference. The wing nut controls the tension on the spool.
Figure 5
5.2.6 Setting the wire spool tension. a) Turn the spool of wire with one hand.
b) Increase the spool tension by tightening (turn clockwise) the wing
nut while turning the spool. Turn the spool while tightening the wing nut
until the spool slows down and you feel a slight drag. Stop tightening
the wing nut; you may need to repeat these steps until proper spool
tension is achieved.
5.2.7 If TOO MUCH tension is applied to the wire spool, the wire will slip on
the drive roller or will not be able to feed at all. If TOO LITTLE tension
is applied, the spool of wire will want to unspool itself when the trigger
is released. Readjust the spool tension using the wing nut as
necessary to correct for either problem.
5.2.8 With the welder disconnected from the power source, remove the
leading end of the wire from the spool. Hold on to it securely, so as
not to allow unspooling or tangling of the wire as it will result in tangled
wire and feeding problems.
4 Inch
8 Inch

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5.2.9 Cut off any bent portion of the wire using a wire cutter.
5.2.10 Loosen the tension adjusting knob holding the drive tension arm in
place and lift the tension arm up off the drive roller.
5.2.11 Insert the wire into the inlet guide tube and feed it across the drive
roller and into the torch assembly about six inches.
-Make certain that the welding wire is actually going into the torch liner. If not, the wire will jam up in
the mechanism.
5.2.12 Line the wire up with the correct groove in the drive roller. Place the
drive tension arm back above the drive roller.
5.2.13 Place the drive tension adjustment arm back in place.
5.2.14 Tighten (turn clockwise) the drive tension adjusting knob until the
tension roller is applying enough force on the wire to prevent it from
slipping in the drive rollers. DO NOT OVER TIGHTEN.
5.2.15 NOW YOU CAN LET GO OF THE WIRE.
5.2.16 Plug in the welder power cord and turn the welder ON. Set the voltage
switch to the voltage setting recommended for the gauge metal that is
to be welded. Refer to the set-up chart on the back side of the drive
compartment door.
-The welding wire is electrically hot when the power is on and the torch trigger is activated.
5.2.17 Set the WIRE SPEED control to the middle of the wire speed range.
5.2.18 Straighten the MIG torch cable and pull the trigger in the gun handle to
feed the wire through the torch assembly. When at least one inch of the
wire sticks out past the end of the torch, release the trigger.
5.2.19 Turn the power switch to the OFF position.
5.2.20 Select a contact tip stamped with the same diameter as the wire being
used. NOTE: Due to inherent variances in flux core welding wire, it may
be necessary to use a contact tip one size larger than your flux core
wire, if wire jams occur.
5.2.21 Slide the contact tip over the wire (protruding from the end of the
torch). Thread the contact tip into the end of the torch and hand-tighten
securely.
5.2.22 Install the nozzle on the torch assembly.
5.2.23 Cut off excess wire that extends past the end of the nozzle more than
1/4 inch.
5.2.24 Turn the welder ON.

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6. SETTING THE DRIVE ROLL TENSION
•Arc flash can injure eyes! To reduce the risk of arc flash, make certain that the wire
coming out of the end of the torch does not come in contact with the work piece, ground
clamp, or any grounded material during the drive tension setting process or arcing will
occur.
6.1 Press the trigger on the torch.
6.2 Turn the drive tension adjustment knob clockwise until the wire seems to feed
smoothly without slipping.
7. GAS INSTALLATION
Shielding gas cylinders and high-pressure cylinders can explode if damaged, so treat them
carefully.
•Never expose cylinders to high heat, sparks, open flames, mechanical shocks or arcs.
•Do not weld on the cylinder.
•Always secure cylinder upright to a cart or stationary object.
•Keep cylinders away from welding or electrical circuits.
•Use the proper regulators, gas hose and fittings for the specific application.
7.1 Polarity Changing - When MIG wire is used, shielding gas is required and the polarity
on this unit needs to be electrode positive.
7.1.1 Electrode Positive for MIG Welding - The Weld Power Cable (see
Figure 8) should be connected to the positive (+) weld output
connection on the front of the machine. The ground cable would then
be connected to the negative (-) weld output connection.
7.1.2 Electrode Negative for Flux Core Welding - The Weld Power Cable
should be connected to the negative (-) weld output connection on the
front of the machine. The ground cable would then be connected to the
positive (+) weld output connection. Refer to the polarity setting label
inside the wire compartment.
7.1.3 Connect one end of the gas hose to the gas hose connection on the
back of the welder. Use a wrench to snug up the connection.

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Reference
Subassembly
1
Gas Bottle Valve
2
Gas Flow Gauge (Set at 20 CFH)
3
Gas Pressure Gauge
4
Regulator
5
Gas Flow Adjuster
6
Gas Hose Connection
7
Gas Cylinder
Figure 6
7.1.4 Connect the other end of the gas hose to the gas hose connection on
the supplied regulator/flow gauge. Use a wrench to snug up the
connection.
7.1.5 Before installing the regulator, it is good practice to make certain no
debris is in the gas bottle connection. Rotate the bottle so the gas
connection is not pointing toward you or any other person. Turn the
valve on the gas bottle clockwise and quickly close. This quick thrust of
gas will clear any debris in the connection. Connect the regulator to the
gas bottle connection. Use a wrench to snug up the connection.
7.1.6 Open the Gas Bottle Valve on the cylinder of gas.
7.1.7 Turn the Gas Flow Adjuster on the regulator so that the gas flow rate is
set at approximately 20 CFH. Make certain you are reading the correct
scale on the gauge.
NOTE: Slowly open the cylinder valve by turning it counter-clockwise until the cylinder pressure
gauge registers on the first gauge of the regulator. Turn the adjustment knob clockwise (right)
slowly to increase gas flow to 20 CFH. To reduce the gas flow, turn the adjustment
counter-clockwise (left). The gas valve is located on the back panel of the welder and activated
by the trigger. Gas flow should be heard when the trigger is activated. No gas flow will result in
a harsh arc with excessive spatter; a smooth weld bead will be difficult to obtain. Avoid
unnecessary gas loss by closing the tank valve when finished welding.
1
7
4
3
2
6
5

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7.1.8 Gas Selection
Different materials require different shielding gases when MIG welding.
(Refer to the set-up chart inside the wire feed compartment.)
Mild Steel: Use 75% Argon and 25% CO2 for reduced spatter and
reduced penetration for thinner materials. DO NOT USE Argon gas
concentrations higher than 75% on steel. The result will be extremely
poor penetration, porosity, and brittleness of weld.
Mild Steel: Use CO2 for deeper penetration but increased spatter. (A
CO2 regulator adapter will be needed.)
Stainless Steel: Use a mixed gas consisting of Helium, Argon, and
CO2.
Aluminum or Bronze: Use 100% Argon.
ASSEMBLY
Electrical Shock
•Electric shock can kill! Always turn the POWER switch OFF and unplug the power cord
from the AC power source before installing wire.
MIG TORCH ASSEMBLY
1. Locate the wing nut retaining bolt inside the front panel on the Drive System (Figure 7). Loosen
the retaining bolt.
Figure 7
2. Make note of the retaining groove on the back end of the MIG torch (Figure 7).
Figure 8
Retaining
Bolt
Retaining
Groove
MIG
Socket
5-Pin Trigger
Receptacle
Positive (+)
Weld Output
Connection
Negative (-)
Weld Output
Connection
Weld Power
Cable

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3. Insert the back end of the MIG torch into the MIG socket on the front of your machine (Figure 8).
Make certain to completely slide the torch all the way in. Slightly twist to assist with pushing the
torch to the back of the receptacle. The retaining bolt can then be tightened, making certain the
bolt sets down into the retaining groove on the back of the MIG torch.
4. Connect the 5-Pin trigger connection on the MIG torch to the 5-Pin trigger receptacle on the front
panel (Figure 8).
5. Connect the ground cable to the negative (-) weld output connection for MIG welding. If welding
with self-shielded flux core, connect the ground cable to the positive (+) weld output connection
and move the Weld Power Cable to the negative (-) weld output connection.
6. Follow the Wire Feed Welding Set-up instructions in the Operating section.
SPOOL GUN ASSEMBLY (OPTIONAL WITH MMWMP242DVIB)
1 This unit is set-up to accept the MMWEZFSG2 gun only.
2 The MMWEZFSG2 has three connection points at the back of the spool gun. (1) The gas
connection is a slide on quick connector. (2) The weld power connection has a round ring
connection. (3) The trigger connection is the 5-Pin snap on connector.
3 We recommend removing the MIG torch when the Spool Gun is connected to avoid accidental
arcing. Loosen the wing nut retaining bolt and slide the MIG torch out of the front of the machine.
Disconnect the 5-Pin trigger connection on the front of the machine.
4 Carefully slide the gas connector and the weld power connection through the weld cable access
opening in the front of the machine (Figure 10).

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Figure 10
5 Open the wire compartment door.
6 Connect the gas connection quick connector to the gas connector (1) on the back panel of the
wire compartment.
7 Connect the weld power connection to the bolt on the top of the MIG connector (2).
8 Connect the 5-Pin trigger connector to the 5-Pin receptacle on the front of the machine (3).
9 See step 11 of WIRE FEED WELDING SET-UP in the Operating Instructions section
DC STICK WELDING ASSEMBLY
- Be aware that the ELECTRODE HOLDER will be electrically HOT when the Input Power Switch on the
welder is turned ON.
1. Install the ground cable quick connector to the negative (-) Weld Output Connector (Figure 8).
2. Secure the ground clamp to the work piece.
3. Install the electrode cable quick connector to the positive (+) Weld Output Connector.
4. Follow the STICK WELDING SET-UP instructions in the Operating Instructions section.
OPTIONAL TIG TORCH ASSEMBLY (OPTIONAL WITH MMWMP242DVIB)
- Be aware that the TIG TORCH will be electrically HOT when the Input Power Switch on the welder is
turned ON.
1. Remove the ground cable and the electrode holder from the weld output connections. Install the
ground cable to the positive (+) weld output connection (Figure 8).
2. Secure the ground clamp to the work piece.
3. Connect a regulator to a bottle of ARGON gas. Then connect the gas connection from the TIG
torch to the regulator.
4. Connect the TIG torch weld cable to the negative (-) weld output connection.
5. Set the desired amperage on the amperage control knob on the front panel of the welder.
6. Turn on the input power switch on the welder.
7. Turn on the regulator on the bottle of shielding gas and adjust the regulator to approximately 20
CFH. Open the shielding gas valve on the torch to start the flow of shielding gas.
Weld Cable
Access
Opening

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OPERATING INSTRUCTIONS
•High voltage danger from power source! Consult a qualified electrician for proper
installation of receptacle. This welder must be grounded while in use to protect the
operator from electrical shock.
•Do not remove grounding prong or alter the plug in any way. Use only the supplied
adapter between the plasma cutter's power cord and the power source receptacle. Make
sure the POWER switch is OFF when connecting your welder’s power cord directly to a
properly grounded 230/120 VAC, 60 HZ, Single Phase, 50/20 Amp input power supply.
UNDERSTANDING THE FRONT PANEL
Reference
Description
1
Home/Start Button
2
Previous Screen Button
3
Voltage Control Knob
4
Multi-Function Adjustment/Selection Knob
5
Wire Jog Button
6
Gas Purge Button
7
LCD Display
1. GENERAL SYSTEM SET-UP
1.1 Press the START BUTTON
1.2 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to the SETTING
selection
1.3 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB.
1.4 LANGUAGE
1.4.1 English is the default selection
1.4.2 To change selection, Press the MULTI-FUNCTION ADJUSTMENT/SELECTION
KNOB.
1
2
3
5
4
6
7

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1.4.3 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to desired
language.
1.4.5 Press the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to confirm your
selection.
1.5 UNIT
1.5.1 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB until UNITS
screen is displayed.
1.5.2 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB. The
selected unit measurement is highlighted.
1.5.3 To change selection, Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION
KNOB to selected desired units’ measurement.
1.5.4 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to confirm
your selection.
1.6 BRIGHTNESS
1.6.1 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB until
BRIGHTNESS screen is displayed.
1.6.2 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB.
1.6.3 To change selection, Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION
KNOB to selected desired screen brightness.
1.6.4 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to confirm
your selection.
1.7 SOFTWARE VERSION
1.7.1 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB until
INFORMATION screen is displayed.
1.7.2 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB.
1.7.3 Software version is displayed.
1.7.4 Push the START BUTTON to exit.
1.8 TO PERFORM A RESET BACK TO FACTORY SETTINGS
1.8.1 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB until FACTORY
RESET screen is displayed.
1.8.2 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB.
1.8.3 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to confirm
desire to do a factory reset.
1.8.4 Push in the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to start
factory reset or press the START BUTTON to exit.
2. WIRE FEED WELDING SET-UP
2.1 Press the START BUTTON
2.2 Turn the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB until the desired
Wire Feed Welding screen is displayed.
2.2.1 MIG Steel - Choose this option if you are MIG welding steel with a shielding gas
or flux core welding steel.
2.2.1.1 Use the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB to
select your shielding gas. Press the MULTI-FUNCTION
ADJUSTMENT/SELECTION KNOB to confirm your selection.
2.2.1.2 Connect the Weld Power Cable (See Figure 8 or follow the
onscreen visual) to the Positive (+) Weld Output Connection.
Press the MULTI-FUNCTION ADJUSTMENT/SELECTION KNOB