Miller Electric 125C Owner's manual

Category
Welding System
Type
Owner's manual

This manual is also suitable for

Spectrum 125C
And ICE-12C Torch
Processes
Description
R
Air Plasma Cutting
and Gouging
Air Plasma Cutter
OM-2248 213 990G
201007
File: Plasma Cutters
Visit our website at
www.MillerWelds.com
Miller Electric manufactures a full line
of welders and welding related equipment.
For information on other quality Miller
products, contact your local Miller distributor to receive the latest full
line catalog or individual specification sheets. To locate your nearest
distributor or service agency call 1-800-4-A-Miller, or visit us at
www.MillerWelds.com on the web.
Thank you and congratulations on choosing Miller. Now you can get
the job done and get it done right. We know you don’t have time to do
it any other way.
That’s why when Niels Miller first started building arc welders in 1929,
he made sure his products offered long-lasting value and superior
quality. Like you, his customers couldn’t afford anything less. Miller
products had to be more than the best they could be. They had to be the
best you could buy.
Today, the people that build and sell Miller products continue the
tradition. They’re just as committed to providing equipment and service
that meets the high standards of quality and value established in 1929.
This Owners Manual is designed to help you get the most out of your
Miller products. Please take time to read the Safety precautions. They
will help you protect yourself against potential hazards on the worksite.
We’ve made installation and operation quick
and easy. With Miller you can count on years
of reliable service with proper maintenance.
And if for some reason the unit needs repair,
there’s a Troubleshooting section that will
help you figure out what the problem is. The
parts list will then help you to decide the
exact part you may need to fix the problem.
Warranty and service information for your
particular model are also provided.
Miller is the first welding
equipment manufacturer in
the U.S.A. to be registered to
the ISO 9001 Quality System
Standard.
Working as hard as you do
every power source from
Miller is backed by the most
hassle-free warranty in the
business.
From Miller to You
Mil_Thank 200909
TABLE OF CONTENTS
SECTION 1 SAFETY PRECAUTIONS - READ BEFORE USING 1..................................
1-1. Symbol Usage 1........................................................................
1-2. Plasma Arc Cutting Hazards 1............................................................
1-3. Additional Symbols For Installation, Operation, And Maintenance 3.............................
1-4. California Proposition 65 Warnings 4.......................................................
1-5. Principal Safety Standards 4.............................................................
1-6. EMF Information 4......................................................................
SECTION 2 CONSIGNES DE SÉCURITÉ LIRE AVANT UTILISATION 1...........................
2-1. Signification des symboles 1.............................................................
2-2. Dangers liés au coupage à l’arc au plasma 1................................................
2-3. Dangers supplémentaires en relation avec l’installation, le fonctionnement
et la maintenance 3.....................................................................
2-4. Proposition californienne 65 Avertissements 5...............................................
2-5. Principales normes de sécurité 5..........................................................
2-6. Informations relatives aux CEM 5.........................................................
SECTION 3 DEFINITIONS 6...................................................................
3-1. Symbols And Definitions For Nameplate And Serial Number/Rating Label 6......................
SECTION 4 INSTALLATION 7..................................................................
4-1. Specifications 7........................................................................
4-2. Specifications For Torch 7................................................................
4-3. Duty Cycle And Overheating 7............................................................
4-4. Serial Number And Rating Label Location 8.................................................
4-5. Selecting A Location 8...................................................................
4-6. Torch Dimensions And Weight 9..........................................................
4-7. Connecting Work Clamp 9...............................................................
4-8. Electrical Service Guide For 120 VAC 9....................................................
4-9. Extension Cord Data 9..................................................................
4-10. Connecting Input Power 10................................................................
SECTION 5 OPERATION 11....................................................................
5-1. Controls 11.............................................................................
5-2. Cutting Speed 12........................................................................
5-3. Trigger Safety Lock 12...................................................................
5-4. Sequence Of Operation 13................................................................
SECTION 6 MAINTENANCE & TROUBLESHOOTING 14...........................................
6-1. Routine Maintenance 14..................................................................
6-2. Overload Protection: Trouble Light And Checking Shield Cup Shutdown System 15.................
6-3. Torch And Work Cable Connections 16......................................................
6-4. Checking/Replacing Retaining Cup, Tip, And Electrode 17......................................
6-5. Compressor Filter Cleaning And Replacement 18.............................................
6-6. Troubleshooting Power Source 19..........................................................
6-7. Troubleshooting Torch 20.................................................................
SECTION 7 ELECTRICAL DIAGRAM 21..........................................................
SECTION 8 PARTS LIST 22.....................................................................
WARRANTY
OM-2248 Page 1
SECTION 1 SAFETY PRECAUTIONS - READ BEFORE USING
pom_201003
Protect yourself and others from injury — read and follow these precautions.
1-1. Symbol Usage
DANGER! Indicates a hazardous situation which, if
not avoided, will result in death or serious injury. The
possible hazards are shown in the adjoining symbols
or explained in the text.
Indicates a hazardous situation which, if not avoided,
could result in death or serious injury. The possible
hazards are shown in the adjoining symbols or ex-
plained in the text.
NOTICE Indicates statements not related to personal injury.
. Indicates special instructions.
This group of symbols means Warning! Watch Out! ELECTRIC
SHOCK, MOVING PARTS, and HOT PARTS hazards. Consult sym-
bols and related instructions below for necessary actions to avoid the
hazards.
1-2. Plasma Arc Cutting Hazards
The symbols shown below are used throughout this manual
to call attention to and identify possible hazards. When you
see the symbol, watch out, and follow the related instructions
to avoid the hazard. The safety information given below is
only a summary of the more complete safety information
found in the Safety Standards listed in Section 1-5. Read and
follow all Safety Standards.
Only qualified persons should install, operate, maintain, and
repair this unit.
During operation, keep everybody, especially children, away.
CUTTING can cause fire or explosion.
Hot metal and sparks blow out from the cutting arc.
The flying sparks and hot metal, hot workpiece, and
hot equipment can cause fires and burns. Check
and be sure the area is safe before doing any cutting.
D Remove all flammables within 35 ft (10.7 m) of the cutting arc. If this
is not possible, tightly cover them with approved covers.
D Do not cut where flying sparks can strike flammable material.
D Protect yourself and others from flying sparks and hot metal.
D Be alert that sparks and hot materials from cutting can easily go
through small cracks and openings to adjacent areas.
D Watch for fire, and keep a fire extinguisher nearby.
D Be aware that cutting on a ceiling, floor, bulkhead, or partition can
cause fire on the hidden side.
D Do not cut on closed containers such as tanks or drums.
D Connect work cable to the work as close to the cutting area as prac-
tical to prevent cutting current from traveling long, possibly unknown
paths and causing electric shock, sparks, and fire hazards.
D Do not use plasma cutter to thaw frozen pipes.
D Never cut containers with potentially flammable materials inside
they must be emptied and properly cleaned first.
D Do not cut where the atmosphere may contain flammable dust,
gas, or liquid vapors (such as gasoline).
D Do not cut pressurized cylinders, pipes, or vessels.
D Do not cut containers that have held combustibles.
D Wear oil-free protective garments such as leather gloves, heavy
shirt, cuffless trousers, high shoes, and a cap.
D Do not locate unit on or over combustible surfaces.
D Remove any combustibles, such as a butane lighter or matches,
from your person before doing any cutting.
D After completion of work, inspect area to ensure it is free of sparks,
glowing embers, and flames.
D Use only correct fuses or circuit breakers. Do not oversize or by-
pass them.
D Follow requirements in OSHA 1910.252 (a) (2) (iv) and NFPA 51B
for hot work and have a fire watcher and extinguisher nearby.
Touching live electrical parts can cause fatal shocks
or severe burns. The torch and work circuit are
electrically live whenever the output is on. The input
power circuit and machine internal circuits are also
live when power is on. Plasma arc cutting requires
higher voltages than welding to start and maintain the arc (200 to 400
volts dc are common), but may also use torches designed with safety
interlock systems which turn off the machine when the shield cup is
loosened or if tip touches electrode inside the nozzle. Incorrectly
installed or improperly grounded equipment is a hazard.
ELECTRIC SHOCK can kill.
D Do not touch live electrical parts.
D Wear dry, hole-free insulating gloves and body protection.
D Insulate yourself from work and ground using dry insulating mats or
covers big enough to prevent any physical contact with the work or
ground.
D Do not touch torch parts if in contact with the work or ground.
D Turn off power before checking, cleaning, or changing torch parts.
D Disconnect input power before installing or servicing this equip-
ment. Lockout/tagout input power according to OSHA CFR
1910.147 (see Safety Standards).
D Properly install and ground this equipment according to its Owner’s
Manual and national, state, and local codes.
D Check and be sure that input power cord ground wire is properly
connected to ground terminal in disconnect box or that cord plug is
connected to a properly grounded receptacle outlet always verify
the supply ground.
D When making input connections, attach proper grounding conduc-
tor first.
D Keep cords dry, free of oil and grease, and protected from hot metal
and sparks.
D Frequently inspect input power cord for damage or bare wiring re-
place cord immediately if damaged bare wiring can kill.
D Turn off all equipment when not in use.
D Inspect and replace any worn or damaged torch cable leads.
D Do not wrap torch cable around your body.
D Ground the workpiece to a good electrical (earth) ground if required
by codes.
D Use only well-maintained equipment. Repair or replace damaged
parts at once.
D Wear a safety harness if working above floor level.
D Keep all panels and covers securely in place.
D Do not bypass or try to defeat the safety interlock systems.
D Use only torch(es) specified in Owners Manual.
D Keep away from torch tip and pilot arc when trigger is pressed.
D Clamp work cable with good metal-to-metal contact to workpiece
(not piece that will fall away) or worktable as near the cut as
practical.
D Insulate work clamp when not connected to workpiece to prevent
contact with any metal object.
OM-2248 Page 2
SIGNIFICANT DC VOLTAGE exists in
inverter power sources AFTER the re-
moval of input power.
D Turn Off unit, disconnect input power, check voltage on input ca-
pacitors, and be sure it is near zero (0) volts before touching any
parts. Check capacitors according to instructions in Mainte-
nance Section of Owners Manual or Technical Manual before
touching any parts.
ELECTRIC SHOCK can kill.
D On inverter power sources, failed parts can ex-
plode or cause other parts to explode when
power is applied. Always wear a face shield
and long sleeves when servicing inverters.
EXPLODING PARTS can injure.
Sparks and hot metal blow out from the cutting arc.
Chipping and grinding cause flying metal.
FLYING SPARKS can injure.
D Wear approved face shield or safety goggles with side shields.
D Wear proper body protection to protect skin.
D Wear flame-resistant ear plugs or ear muffs to prevent sparks from
entering ears.
Arc rays from the cutting process produce intense
visible and invisible (ultraviolet and infrared) rays
that can burn eyes and skin.
ARC RAYS can burn eyes and skin.
D Wear face protection (helmet or shield) with a proper shade of filter
lenses to protect your face and eyes from arc rays and sparks when
cutting or watching. ANSI Z49.1 (see Safety Standards) suggests a
No. 9 shade (with No. 8 as minimum) for all cutting currents less
than 300 amperes. Z49.1 adds that lighter filter shades may be used
when the arc is hidden by the workpiece. As this is normally the case
with low current cutting, the shades suggested in Table 1 are pro-
vided for the operator’s convenience.
D Wear approved safety glasses with side shields under your helmet
or shield.
D Use protective screens or barriers to protect others from flash, glare
and sparks; warn others not to watch the arc.
D Wear protective clothing made from durable, flame-resistant
material (leather, heavy cotton, or wool) and foot protection.
Table 1. Eye Protection For Plasma Arc Cutting
Current Level In Amperes Minimum Shade Number
Below 20
20 40
40 60
60 100
#4
#5
#6
#8
Prolonged noise from some cutting applications can
damage hearing if levels exceed limits specified by
OSHA (see Safety Standards).
NOISE can damage hearing.
D Use approved ear plugs or ear muffs if noise level is high.
D Warn others nearby about noise hazard.
FUMES AND GASES can be hazardous.
Cutting produces fumes and gases. Breathing
these fumes and gases can be hazardous to
your health.
D Keep your head out of the fumes. Do not breathe the fumes.
D If inside, ventilate the area and/or use local forced ventilation at the
arc to remove cutting fumes and gases.
D If ventilation is poor, wear an approved air-supplied respirator.
D Read and understand the Material Safety Data Sheets (MSDSs)
and the manufacturer’s instruction for metals to be cut, coatings,
and cleaners.
D Work in a confined space only if it is well ventilated, or while wearing
an air-supplied respirator. Fumes from cutting and oxygen depletion
can alter air quality causing injury or death. Be sure the breathing air
is safe.
D Do not cut in locations near degreasing, cleaning, or spraying oper-
ations. The heat and rays of the arc can react with vapors to form
highly toxic and irritating gases.
D Do not cut on coated metals, such as galvanized, lead, or cadmium
plated steel, unless the coating is removed from the cutting area, the
area is well ventilated, and while wearing an air-supplied respirator.
The coatings and any metals containing these elements can give off
toxic fumes when cut.
D Do not cut containers with toxic or reactive materials inside or
containers that have held toxic or reactive materials they must be
emptied and properly cleaned first.
PLASMA ARC can injure.
The heat from the plasma arc can cause serious
burns. The force of the arc adds greatly to the burn
hazard. The intensely hot and powerful arc can
quickly cut through gloves and tissue.
D Keep away from the torch tip.
D Do not grip material near the cutting path.
D The pilot arc can cause burns keep away from torch tip when trig-
ger is pressed.
D Wear proper flame-retardant clothing covering all exposed body ar-
eas.
D Point torch away from your body and toward work when pressing
the torch trigger pilot arc comes on immediately.
D Turn off power source and disconnect input power before disas-
sembling torch or changing torch parts.
D Use only torch(es) specified in the Owners Manual.
Gas cylinders contain gas under high pressure. If
damaged, a cylinder can explode. Since gas cylin-
ders are normally part of metalworking processes,
be sure to treat them carefully.
CYLINDERS can explode if damaged.
D Protect compressed gas cylinders from excessive heat, mechani-
cal shocks, physical damage, slag, open flame, sparks, and arcs.
D Install and secure cylinders in an upright position by chaining them
to a stationary support or equipment cylinder rack to prevent falling
or tipping.
D Keep cylinders away from any cutting or other electrical circuits.
D Never allow electrical contact between a plasma arc torch and a
cylinder.
D Never cut on a pressurized cylinder explosion will result.
D Use only correct gas cylinders, regulators, hoses, and fittings de-
signed for the specific application; maintain them and associated
parts in good condition.
D Turn face away from valve outlet when opening cylinder valve.
D Keep protective cap in place over valve except when cylinder is in
use or connected for use.
D Use the right equipment, correct procedures, and sufficient number
of persons to lift and move cylinders.
D Read and follow instructions on compressed gas cylinders, asso-
ciated equipment, and Compressed Gas Association (CGA)
publication P-1 listed in Safety Standards.
OM-2248 Page 3
1-3. Additional Symbols For Installation, Operation, And Maintenance
HOT PARTS can burn.
D Do not touch hot parts bare handed.
D Allow cooling period before working on
equipment.
D To handle hot parts, use proper tools and/or
wear heavy, insulated welding gloves and
clothing to prevent burns.
MOVING PARTS can injure.
D Keep away from moving parts such as fans.
D Keep all doors, panels, covers, and guards
closed and securely in place.
D Have only qualified persons remove doors, panels, covers, or
guards for maintenance and troubleshooting as necessary.
D Reinstall doors, panels, covers, or guards when maintenance is
finished and before reconnecting input power.
READ INSTRUCTIONS.
D Read and follow all labels and the Owners
Manual carefully before installing, operating, or
servicing unit. Read the safety information at
the beginning of the manual and in each
section.
D Use only genuine replacement parts from the manufacturer.
D Perform maintenance and service according to the Owners
Manuals, industry standards, and national, state, and local
codes.
FLYING METAL or DIRT can injure eyes.
D Wear safety glasses with side shields or wear
face shield.
ELECTRIC AND MAGNETIC FIELDS (EMF)
can affect Implanted Medical Devices.
D Wearers of Pacemakers and other Implanted
Medical Devices should keep away.
D Implanted Medical Device wearers should consult their doctor
and the device manufacturer before going near arc welding, spot
welding, gouging, plasma arc cutting, or induction heating
operations.
OVERUSE can cause OVERHEATING.
D Allow cooling period; follow rated duty cycle.
D Reduce amperage (thickness) or reduce duty
cycle before starting to cut again.
EXPLODING HYDROGEN hazard.
D When cutting aluminum underwater or with the
water touching the underside of the aluminum,
free hydrogen gas may collect under the work-
piece.
D See your cutting engineer and water table instructions for help.
FALLING EQUIPMENT can injure.
D Use lifting eye to lift unit only, NOT running
gear, gas cylinders, or any other accessories.
D Use equipment of adequate capacity to lift unit.
D If using lift forks to move unit, be sure forks are long enough to ex-
tend beyond opposite side of unit.
D Keep equipment (cables and cords) away from moving vehicles
when working from an aerial location.
D Follow the guidelines in the Applications Manual for the Revised
NIOSH Lifting Equation (Publication No. 94110) when manually
lifting heavy parts or equipment.
FIRE OR EXPLOSION hazard.
D Do not locate unit on, over, or near combustible
surfaces.
D Do not install unit near flammables.
D Do not overload building wiring be sure power supply system is
properly sized, rated, and protected to handle this unit.
STATIC (ESD) can damage PC boards.
D Put on grounded wrist strap BEFORE handling
boards or parts.
D Use proper static-proof bags and boxes to
store, move, or ship PC boards.
H.F. RADIATION can cause interference.
D High frequency (H.F.) can interfere with radio
navigation, safety services, computers, and
communications equipment.
D Have only qualified persons familiar with elec-
tronic equipment perform this installation.
D The user is responsible for having a qualified electrician promptly
correct any interference problem resulting from the installation.
D If notified by the FCC about interference, stop using the equipment
at once.
D Have the installation regularly checked and maintained.
D Keep high-frequency source doors and panels tightly shut, keep
spark gaps at correct setting, and use grounding and shielding to
minimize the possibility of interference.
ARC CUTTING can cause interference.
D Electromagnetic energy can interfere with
sensitive electronic equipment such as
computers and computer-driven equipment
such as robots.
D To reduce possible interference, keep cables as short as possible,
close together, and down low, such as on the floor.
D Locate cutting operation 100 meters from any sensitive electronic
equipment.
D Be sure this cutting power source is installed and grounded
according to this manual.
D If interference still occurs, the user must take extra measures such
as moving the machine, using shielded cables, using line filters, or
shielding the work area.
OM-2248 Page 4
1-4. California Proposition 65 Warnings
Welding or cutting equipment 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 Section 25249.5 et seq.)
Battery posts, terminals and related accessories contain lead
and lead compounds, chemicals known to the State of
California to cause cancer and birth defects or other
reproductive harm. Wash hands after handling.
This product contains chemicals, including lead, known to
the state of California to cause cancer, birth defects, or other
reproductive harm. Wash hands after use.
For Gasoline Engines:
Engine exhaust contains chemicals known to the State of
California to cause cancer, birth defects, or other reproduc-
tive harm.
For Diesel Engines:
Diesel engine exhaust and some of its constituents are known
to the State of California to cause cancer, birth defects, and
other reproductive harm.
1-5. Principal Safety Standards
Safety in Welding, Cutting, and Allied Processes, ANSI Standard Z49.1,
from Global Engineering Documents (phone: 1-877-413-5184, website:
www.global.ihs.com).
Recommended Practices for Plasma Arc Cutting and Gouging, Ameri-
can Welding Society Standard AWS C5.2, from Global Engineering
Documents (phone: 1-877-413-5184, website: www.global.ihs.com).
Safe Practices for the Preparation of Containers and Piping for Welding
and Cutting, American Welding Society Standard AWS F4.1, from Glob-
al Engineering Documents (phone: 1-877-413-5184, website:
www.global.ihs.com).
National Electrical Code, NFPA Standard 70, from National Fire Protec-
tion Association, Quincy, MA 02269 (phone: 1-800-344-3555, website:
www.nfpa.org and www. sparky.org).
Safe Handling of Compressed Gases in Cylinders, CGA Pamphlet P-1,
from Compressed Gas Association, 4221 Walney Road, 5th Floor,
Chantilly, VA 20151 (phone: 703-788-2700, website:www.cganet.com).
Safety in Welding, Cutting, and Allied Processes, CSA Standard
W117.2, from Canadian Standards Association, Standards Sales, 5060
Spectrum Way, Suite 100, Ontario, Canada L4W 5NS (phone:
800-463-6727, website: www.csa-international.org).
Safe Practice For Occupational And Educational Eye And Face Protec-
tion, ANSI Standard Z87.1, from American National Standards Institute,
25 West 43rd Street, New York, NY 10036 (phone: 212-642-4900, web-
site: www.ansi.org).
Standard for Fire Prevention During Welding, Cutting, and Other Hot
Work, NFPA Standard 51B, from National Fire Protection Association,
Quincy, MA 02269 (phone: 1-800-344-3555, website: www.nfpa.org.
OSHA, Occupational Safety and Health Standards for General Industry,
Title 29, Code of Federal Regulations (CFR), Part 1910, Subpart Q, and
Part 1926, Subpart J, from U.S. Government Printing Office, Superin-
tendent of Documents, P.O. Box 371954, Pittsburgh, PA 15250-7954
(phone: 1-866-512-1800) (there are 10 OSHA Regional Offices—phone
for Region 5, Chicago, is 312-353-2220, website: www.osha.gov).
Applications Manual for the Revised NIOSH Lifting Equation, The Na-
tional Institute for Occupational Safety and Health (NIOSH), 1600
Clifton Rd, Atlanta, GA 30333 (phone: 1-800-232-4636, website:
www.cdc.gov/NIOSH).
1-6. EMF Information
Electric current flowing through any conductor causes localized electric
and magnetic fields (EMF). Welding current creates an EMF field around
the welding circuit and welding equipment. EMF fields may interfere with
some medical implants, e.g. pacemakers. Protective measures for per-
sons wearing medical implants have to be taken. For example, access
restrictions for passersby or individual risk assessment for welders. All
welders should use the following procedures in order to minimize expos-
ure to EMF fields from the welding circuit:
1. Keep cables close together by twisting or taping them, or using a
cable cover.
2. Do not place your body between welding cables. Arrange cables
to one side and away from the operator.
3. Do not coil or drape cables around your body.
4. Keep head and trunk as far away from the equipment in the weld-
ing circuit as possible.
5. Connect work clamp to workpiece as close to the weld as
possible.
6. Do not work next to, sit or lean on the welding power source.
7. Do not weld whilst carrying the welding power source or wire
feeder.
About Implanted Medical Devices:
Implanted Medical Device wearers should consult their doctor and the
device manufacturer before performing or going near arc welding, spot
welding, gouging, plasma arc cutting, or induction heating operations.
If cleared by your doctor, then following the above procedures is recom-
mended.
OM-2248 Page 5
2-4. Proposition californienne 65 Avertissements
Les équipements de soudage et de coupage produisent des
fumées et des gaz qui contiennent des produits chimiques
dont l’État de Californie reconnaît qu’ils provoquent des mal-
formations congénitales et, dans certains cas, des cancers.
(Code de santé et de sécurité de Californie, chapitre 25249.5
et suivants)
Ce produit contient des produits chimiques, compris du
plomb, dont l’État de Californie reconnaît qu’ils provoquent
des cancers et des malformations congénitales ou autres
problèmes de procréation. Se laver les mains après
manipulation.
Ce produit contient des éléments chimiques, dont le plomb,
reconnus par l’État de Californie pour leur caractère
cancérogène ainsi que provoquant des malformations
congénitales ou autres problèmes de procréation. Se laver les
mains après toute manipulation.
Pour les moteurs à essence :
Les gaz d’échappement des moteurs contiennent des pro-
duits chimiques dont l’État de Californie reconnaît qu’ils
provoquent des cancers et des malformations congénitales
ou autres problèmes de procréation.
Pour les moteurs diesel :
Les gaz d’échappement des moteurs diesel et certains de
leurs composants sont reconnus par l’État de Californie com-
me provoquant des cancers et des malformations
congénitales ou autres problèmes de procréation.
2-5. Principales normes de sécuri
Safety in Welding, Cutting, and Allied Processes, ANSI Standard Z49.1,
de Global Engineering Documents (téléphone : 1-877-413-5184, site In-
ternet : www.global.ihs.com).
Recommended Practices for Plasma Arc Cutting and Gouging, Ameri-
can Welding Society Standard AWS C5.2, de Global Engineering
Documents (téléphone : 1-877-413-5184, site internet :
www.global.ihs.com).
Safe Practices for the Preparation of Containers and Piping for Welding
and Cutting, American Welding Society Standard AWS F4.1, de Global
Engineering Documents (téléphone: 1-877-413-5184, site internet :
www.global.ihs.com).
National Electrical Code, NFPA Standard 70, de National Fire Protection
Association, Quincy, MA 02269 (téléphone : 1-800-344-3555, site Inter-
net : www.nfpa.org et www.sparky.org).
Safe Handling of Compressed Gases in Cylinders, CGA Pamphlet P-1,
de Compressed Gas Association, 4221 Walney Road, 5th Floor, Chan-
tilly, VA 20151 (téléphone : 703-788-2700, site Internet :
www.cganet.com).
Safety in Welding, Cutting, and Allied Processes, CSA Standard
W117.2, de Canadian Standards Association, Standards Sales, 5060
Spectrum Way, Suite 100, Ontario, Canada L4W 5NS (téléphone :
800-463-6727, site internet : www.csa-international.org).
Safe Practice For Occupational And Educational Eye And Face Protec-
tion, ANSI Standard Z87.1, de American National Standards Institute,
25 West 43rd Street, New York, NY 10036 (téléphone : 212-642-4900,
site Internet : www.ansi.org).
Standard for Fire Prevention During Welding, Cutting, and Other Hot
Work, NFPA Standard 51B, de National Fire Protection Association,
Quincy, MA 02269 (téléphone : 1-800-344-3555, site Internet :
www.nfpa.org).
OSHA, Occupational Safety and Health Standards for General Industry,
Title 29, Code of Federal Regulations (CFR), Part 1910, Subpart Q, and
Part 1926, Subpart J, de U.S. Government Printing Office, Superinten-
dent of Documents, P.O. Box 371954, Pittsburgh, PA 15250-7954
(téléphone : 1-866-512-1800) (il y a 10 bureaux régionaux le téléphone
de la région 5, Chicago, est 312-353-2220, site Internet :
www.osha.gov).
Applications Manual for the Revised NIOSH Lifting Equation, The Na-
tional Institute for Occupational Safety and Health (NIOSH), 1600
Clifton Rd, Atlanta, GA 30333
(téléphone: 1-800-232-4636, site internet : www.cdc.gov/NIOSH).
2-6. Informations relatives aux CEM
Le courant électrique qui traverse tout conducteur génère des champs
électromagnétiques (CEM) à certains endroits. Le courant de soudage
crée un CEM autour du circuit et du matériel de soudage. Les CEM
peuvent créer des interférences avec certains implants médicaux
comme des stimulateurs cardiaques. Des mesures de protection pour
les porteurs d’implants médicaux doivent être prises: par exemple, des
restrictions d’accès pour les passants ou une évaluation individuelle
des risques pour les soudeurs. Tous les soudeurs doivent appliquer les
procédures suivantes pour minimiser l’exposition aux CEM provenant
du circuit de soudage:
1. Rassembler les câbles en les torsadant ou en les attachant avec
du ruban adhésif ou avec une housse.
2. Ne pas se tenir au milieu des câbles de soudage. Disposer les
câbles d’un côté et à distance de l’opérateur.
3. Ne pas courber et ne pas entourer les câbles autour de votre
corps.
4. Maintenir la tête et le torse aussi loin que possible du matériel du
circuit de soudage.
5. Connecter la pince sur la pièce aussi près que possible de la
soudure.
6. Ne pas travailler à proximité d’une source de soudage, ni
s’asseoir ou se pencher dessus.
7. Ne pas souder tout en portant la source de soudage ou le
dévidoir.
En ce qui concerne les implants médicaux :
Les porteurs d’implants doivent d’abord consulter leur médecin avant de
s’approcher des opérations de soudage à l’arc, de soudage par points,
de gougeage, du coupage plasma ou de chauffage par induction. Si le
médecin approuve, il est recommandé de suivre les procédures précé-
dentes.
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 6
SECTION 3 DEFINITIONS
3-1. Symbols And Definitions For Nameplate And Serial Number/Rating Label
A
Amperes
Plasma Arc Cutting
(PAC)
Adjust Air/Gas
Pressure
Low Air Pressure
Light
V
Volts Increase
No Do Not Do
This
Temperature
Protective Earth
(Ground)
Single Phase Constant Current Voltage Input
On Off Percent Direct Current
U
0
Rated No Load
Voltage (Average) U
1
Primary Voltage
U
2
Conventional Load
Voltage
Line Connection
I
1max
Rated Maximum
Supply Current
I
2
Rated Welding
Current X
Duty Cycle
1 f1
f2
Single Phase
Static Frequency
Transformer-
Rectifier-Converter
IP
Degree Of
Protection
Loose Shield Cup Input
Hz
Hertz
I
1eff
Maximum Effective
Supply Current
pf
power factor
S
Suitable for Some
Hazardous
Locations
S
1
Power Rating,
Product Of Voltage
And Current (KVA)
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 7
SECTION 4 INSTALLATION
4-1. Specifications
Primary
Volts
Primary
Amperes
Primary Service
(Recommended)
Secondary
Volts (DC)
Secondary
Amperes
KW KVA
Rated
Cutting
Capacity
Power
Factor
Max**
OCV
(DC)
120
20.32
(0.25*)
20A 110 12 2.01 2.44
0.25 in
(6.4 mm)
At 6 IPM
(2.5 mm/s)
0.82 375
*While idling
**10% High line condition
4-2. Specifications For Torch
Air-cooled torch for plasma arc cutting (PAC)
35% duty cycle
Compressor output: 1.2 scfm (28.3 L/min) at 40 PSI (276 kPa) at 700 ft (213 m)
Safety interlock devices shut down power source
Safety trigger guard
Cutting capacity: see Section 4-1
4-3. Duty Cycle And Overheating
Duty Cycle is percentage of 10 min-
utes that unit can cut at rated load
without overheating.
If unit overheats, thermostat(s)
opens, output stops, Temperature
trouble light goes On, and cooling
fan runs. Wait fifteen minutes for
unit to cool or temperature light to
go off. Reduce amperage or duty
cycle before cutting or gouging.
NOTICE Exceeding duty cycle
can damage unit or gun and void
warranty.
Overheating
duty1 4/95
3-1/2 Minutes Cutting 6-1/2 Minutes Resting
0
15
Minutes
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 8
4-4. Serial Number And Rating Label Location
The serial number and rating information for this product is located on the back. Use rating label to determine input power requirements and/or rated
output. For future reference, write serial number in space provided on back cover of this manual.
18 in.
(457 mm)
4-5. Selecting A Location
loc_2 3/96
1 Lifting Handle
Use handle to lift unit.
2 Hand Cart
Use cart or similar device to move
unit.
3 120 VAC, 20 A Receptacle
Locate unit near correct input
power supply.
! Special installation may be
required where gasoline or
volatile liquids are present
see NEC Article 511 or CEC
Section 20.
6-3/4 in.
(171 mm)
Movement
1
2
Location And Airflow
Dimensions And Weight
31 lb (14 kg)
10 in.
(254 mm)
10 in.
(254 mm)
3
17 in.
(432 mm)
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 9
4-6. Torch Dimensions And Weight
Ref. 801 397-A
3.0 lb (1.4 kg)
1 in.
(25 mm)
8-3/8 in.
(213 mm)
1-3/8 in.
(35 mm)
4-7. Connecting Work Clamp
Ref 803 915-A
. Do not connect work clamp to
the portion of the workpiece
that will fall when cut.
1 Work Clamp
2 Workpiece
Connect work clamp to a clean,
paint-free location on workpiece, as
close to cutting area as possible.
1
2
4-8. Electrical Service Guide For 120 VAC
Failure to follow these electrical service guide recommendations could create an electric shock or fire hazard. These
recommendations are for a dedicated branch circuit sized for the rated output and duty cycle of the welding power source.
50/60 Hz
Single
Phase
Input Voltage (V) 120
Input Amperes (A) At Rated Output 19
Max Recommended Standard Fuse Rating In Amperes
1
Time-Delay Fuses
2
20
Normal Operating Fuses
3
30
Min Input Conductor Size In AWG
4
12
Max Recommended Input Conductor Length In Feet (Meters)
34
(10)
Min Grounding Conductor Size In AWG
4
12
Reference: 2008 National Electrical Code (NEC) (including article 630)
1 If a circuit breaker is used in place of a fuse, choose a circuit breaker with time-current curves comparable to the recommended fuse.
2 “Time-Delay” fuses are UL class “RK5” . See UL 248.
3 “Normal Operating” (general purpose - no intentional delay) fuses are UL class “K5” (up to and including 60 amps), and UL class “H” ( 65 amps and
above).
4 Conductor data in this section specifies conductor size (excluding flexible cord or cable) between the panelboard and the equipment per NEC Table
310.16. If a flexible cord or cable is used, minimum conductor size may increase. See NEC Table 400.5(A) for flexible cord and cable requirements.
4-9. Extension Cord Data
Input Voltage
Input Power
Phase
Hertz Conductor Size Max. Cord Length
120 V 1 50/60 12 AWG 50 ft (15 m)
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 10
4-10. Connecting Input Power
Ref. 802 460-B
Check input voltage available at
site.
1 Grounded Receptacle
A 120 volts AC, 20 ampere
individual branch circuit protected
by time-delay fuses or circuit
breaker is required (see Section
4-8).
2 Plug From Unit
Connect plug to receptacle.
For extension cord data, see
Section 4-9.
! Special installation may be
required where gasoline or
volatile liquids are present
see NEC Article 511 or CEC
Section 20.
1
120 V 20 A
Receptacle
2
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 11
SECTION 5 OPERATION
5-1. Controls
2
Ref. 245 701-A
1
1 Power Switch
The cooling fan will run for a few seconds after
the power switch is placed in the OFF position
in order to discharge internal circuitry.
2 Power Light
Use light to tell if unit is energized and ready to
operate. Light blinks if input power is not within
specified range .
3 Cup Light
Light comes on if cup is removed from torch.
Once cup is reinstalled on torch, unit power
must be turned off and back on again.
4 Temp Light
Light comes on if unit overheats.
3
4
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 12
5-2. Cutting Speed
The cutting speed curve shows the
recommended maximum cutting
speed capabilities of the power
source and torch for mild steel of
various thickness.
The best cut quality is achieved by
cutting near the chart line. Cutting
below the line (too slow) will result
in excess dross. Cutting above the
line (too fast) will cause blowback
and lack of penetration.
. Recommended production cutting speed vs. material thickness is approximately
10 ipm at 1/8 in (3.2 mm) mild steel thickness at max setting.
5-3. Trigger Safety Lock
Trigger Locked Trigger Unlocked
1 Trigger
801 545-A
1
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 13
out bottom of cut.
801 400-A
5-4. Sequence Of Operation
After cutting arc starts, slowly
start moving torch across metal.
Adjust torch speed so
sparks go thru metal and
Pause briefly at end of
cut before releasing trigger.
EXAMPLE Of Cutting Operation
Raise trigger lock and press
trigger. Pilot arc starts.
Postflow continues after releasing trigger;
cutting arc can be instantly restarted during
postflow by raising trigger lock and pressing
trigger.
! The pilot arc starts immediately when trigger is pressed.
For shielded cutting, place drag shield on edge
of metal. For non-shielded cutting, use 1/8 in.
(3.2 mm) standoff distance (dragging tip will
reduce tip life).
. Moisture from the compressor will form in the air line and at
the torch. It will be normal to sometimes see moisture come
out the end of the torch.
As a convenience, the torch can be set up
with two cutting combinations, either drag
or non-shielded cutting. The torch comes
standard with drag cutting.
. Maximum performance on thicker materials can be obtained by using
non-shielded cutting with a 1/16 - 1/8 in (1.6 - 3.2 mm) standoff.
197 567
196 929
Use retaining cup (197 567) and drag
shield (196 929) to obtain a 1/16 in
(1.6 mm) standoff automatically. This
combination is designed to allow
dragging the torch directly on the
workpiece.
Use shields for ease of use when
cutting with a template, or when drag
cutting is preferred.
Drag Cutting
196 926
196 928
1/16-1/8 in
(1.6-3.2 mm)
standoff
workpiece
Use retaining cup (196 928) and hold a
1/16-1/8 in (1.6-3.2 mm) standoff between
the workpiece and cutting tip.
Use non-shielded when visually following
a line.
. This combination can be used for drag
cutting but does not provide optimum
cutting performance on thicker material.
Non-Shielded Cutting
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 14
SECTION 6 MAINTENANCE & TROUBLESHOOTING
6-1. Routine Maintenance
! Disconnect power
before maintaining.
. Maintain more often
during severe conditions.
n = Check Z = Change ~ = Clean l = Replace
* To be done by Factory Authorized Service Agent
Reference
Each
Use
n Torch Tip, Electrode,
And Shield Cup
Every
Week
n Shield Cup Shutdown
System
Every
3
Months
l Unreadable Labels nl Torch Body, Cable n Tape Torn Outer
Covering
nl Cracked Parts
Every
6
Months
OR
nl Compressor Filter
Clean With A Damp Cloth
Or Replace If Necessary
~ Inside Unit
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 15
6-2. Overload Protection: Trouble Light And Checking Shield Cup Shutdown System
1 Power Light
Light is steady if input power is
okay. Light flashes if input power is
less than 92 volts AC or greater
than 136 volts AC. Light stops
flashing 15 seconds after condition
is corrected or when torch trigger is
pressed.
If certain problems occur, the
trouble light comes on, and output
stops.
2 Cup Light
Lights if shield cup is loose/off.
Check shield cup shutdown system
as follows:
Turn power On and loosen shield
cup. If shutdown system works
properly, Cup light comes on. If
not, turn power Off and have a
factory authorized service agent
check unit.
If system works properly,
retighten cup. Power must be
reset whenever the cup
shutdown is activated.
Check shield cup shutdown
system once a week.
A flashing Cup light indicates that
the torch consumables are stuck
or worn and should be inspected
and/or replaced (see
Section 6-4).
3 Temp Light
Lights if power source overheats or
when ambient temperature is below
40° C (40° F). If unit overheats,
allow fan to cool unit for 15 minutes
(see Sections 4-3).
4 Power/Temp Lights
When both lights flash, the com-
pressor current limit was exceeded
either above or below its operating
range. The lights flash for 15 sec-
onds before the torch can be retrig-
gered. If this condition continues
during unit operation, have a facto-
ry authorized service agent check
unit.
5 Torch Shield Cup
Turn Power On and loosen shield
cup. If shutdown system works
properly, trouble light comes on. If
not, turn power Off and check for
loose shield cup.
Check consumables (see Section
6-4 and Parts List).
If system works properly, retighten
cup and reset power.
Ref. 245 701-A / Ref. 801 300-A
Checking Torch Shield Cup Shutdown System
. Power source Power switch must be reset whenever cup shutdown
system is activated. Always turn Off power source when changing or
checking consumables.
5
1
2
3
4
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 16
6-3. Torch And Work Cable Connections
If torch or work cable needs to be
removed or replaced, proceed as
follows:
Turn power Off, and disconnect
input power plug from receptacle.
Remove wrapper from unit.
Torch Connections
Remove existing torch cable from
unit.
1 Strain Relief
2 Torch Cable
Insert cable through strain relief.
Slide strain relief nut onto torch
cable, but do not tighten.
3 Air Line Connector
Install air line connector into torch
fitting.
4 Plug PLG4/Receptacle RC4
Connect PLG4 to receptacle RC4
on circuit board PC1.
5 Female And Male Friction
Terminal RC1/ELECT WHITE
Connect female friction terminal on
end of white leads to RC1/ELECT
WHITE.
6 Female And Male Friction
Terminal RC2/TIP RED
Connect female friction terminal on
end red leads to RC2/TIP RED.
Tighten strain relief nut.
Tighten strain relief around cable.
. Do not overtighten strain relief
onto torch cable.
Work Cable Connections
Remove existing work cable from
unit.
7 Work Cable Strain Relief
. Be sure to allow some work
cable slack inside the unit.
Insert work clamp lead and strain
relief, and install strain relief into
front panel.
8 Work Lead Male Friction
Terminal RC3/WORK BLACK
Connect work clamp lead to male
friction terminal labeled WORK on
circuit board PC1. Route lead along
torch lead bundle.
Tools Needed:
5/8 in.
Ref. 801 300-B
3
2
4
5
6
7
5
4
6
8
1
2
3
. A complete Parts List is available at www.MillerWelds.com
OM-2248 Page 17
6-4. Checking/Replacing Retaining Cup, Tip, And Electrode
! Overtightening will strip threads. Do not overtighten retaining cup
during assembly. Do not cross-thread parts causing stripping.
Use care during torch assembly and parts replacement.
! Inspect shield cup, tip, and electrode for wear before cutting or whenever cutting speed has been
significantly reduced. Do not operate torch without a tip or electrode in place. Be sure to use genuine
replacement parts.
. A good practice is to replace both the tip and electrode at the same time.
802 465
Turn Off power source.
1 Shield Cup
2 O-Ring
Remove shield cup. Check cup for cracks,
and replace if necessary.
Check O-ring for cracks or worn spots, re-
place shield cup if necessary.
3Tip
4 Opening
Remove tip. Check tip, and replace if open-
ing is deformed or 50% oversize. If inside of
tip is not clean and bright, clean with steel
wool. Be sure to remove any pieces of steel
wool afterwards.
5 Electrode
Check electrode. If center has a pit more
than a 1/16 in (2 mm) deep, remove and re-
place electrode.
6 Swirl Ring
7 O-Ring
Remove swirl ring. Check ring, and replace
if side holes are plugged.
Check O-ring for cracks or worn spots,
replace swirl ring if necessary.
8 O-Ring
Check O-ring for cracks or worn spots, and
replace if necessary.
Carefully reassemble parts in reverse order.
Make sure this area is clean of
any debris.
Make sure swirl ring is clean of any
debris and no holes are
obstructed.
! Turn Off power source before checking torch parts.
New
Worn
New
Worn
5
1/16 in
(2 mm)
Pit
4
3
6
1
2
7
8
  • Page 1 1
  • Page 2 2
  • Page 3 3
  • Page 4 4
  • Page 5 5
  • Page 6 6
  • Page 7 7
  • Page 8 8
  • Page 9 9
  • Page 10 10
  • Page 11 11
  • Page 12 12
  • Page 13 13
  • Page 14 14
  • Page 15 15
  • Page 16 16
  • Page 17 17
  • Page 18 18
  • Page 19 19
  • Page 20 20
  • Page 21 21
  • Page 22 22
  • Page 23 23
  • Page 24 24
  • Page 25 25
  • Page 26 26
  • Page 27 27
  • Page 28 28
  • Page 29 29
  • Page 30 30
  • Page 31 31
  • Page 32 32
  • Page 33 33
  • Page 34 34
  • Page 35 35
  • Page 36 36

Miller Electric 125C Owner's manual

Category
Welding System
Type
Owner's manual
This manual is also suitable for

Ask a question and I''ll find the answer in the document

Finding information in a document is now easier with AI

in other languages