Lincoln Electric Idealarc DC-1500 User manual

IDEALARC® DC1500
Operator’s Manual
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Date Purchased
Code: (ex: 10859)
Serial: (ex: U1060512345)
IM318-C | Issue Date 11-Nov
© Lincoln Global, Inc. All Rights Reserved.
For use with machines having Code Numbers:
8294 and above
Register your machine:
www.lincolnelectric.com/register
Authorized Service and Distributor Locator:
www.lincolnelectric.com/locator

THANK YOU FOR SELECTING
A QUALITY PRODUCT BY
LINCOLN ELEC TRIC.
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
incoln 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.
This statement appears where the information must be followed
exactly to avoid serious personal injury or loss of life.
This statement appears where the information must be followed
to avoid minor personal injury or damage to this equipment.
KEEP YOUR HEAD OUT OF THE FUMES.
DON’T get too close to the arc.
Use corrective lenses if necessary
to stay a reasonable distance
away from the arc.
READ and obey the Safety Data
Sheet (SDS) and the warning label
that appears on all containers of
welding materials.
USE ENOUGH VENTILATION or
exhaust at the arc, or both, to
keep the fumes and gases from
your breathing zone and the general area.
IN A LARGE ROOM OR OUTDOORS, natural ventilation may be
adequate if you keep your head out of the fumes (See below).
USE NATURAL DRAFTS or fans to keep the fumes away
from your face.
If you de velop unusual symptoms, see your supervisor.
Perhaps the welding atmosphere and ventilation system
should be checked.
EAR CORRECT EYE, EAR &
BODY PROTECTION
PROTECT your eyes and face with welding helmet
properly fitted and with proper grade of filter plate
(See ANSI Z49.1).
PROTECT your body from welding spatter and arc
flash with protective clothing including woolen
clothing, flame-proof apron and gloves, leather
leggings, and high boots.
PROTECT others from splatter, flash, and glare
with protective screens or barriers.
IN SOME AREAS, protection from noise may be appropriate.
BE SURE protective equipment is in good condition.
Also, wear safety glasses in work area
AT ALL TIMES.
SPECIAL SITUATIONS
DO NOT WELD OR CUT containers or materials which previously
had been in contact with hazardous substances unless they are
properly cleaned. This is extremely dangerous.
DO NOT WELD OR CUT painted or plated parts unless special
precautions with ventilation have been taken. They can release
highly toxic fumes or gases.
Additional precautionary measures
PROTECT compressed gas cylinders from excessive heat,
mechanical shocks, and arcs; fasten cylinders so they cannot fall.
BE SURE cylinders are never grounded or part of an
electrical circuit.
REMOVE all potential fire hazards from welding area.
ALWAYS HAVE FIRE FIGHTING EQUIPMENT READY FOR
IMMEDIATE USE AND KNOW HOW TO USE IT.
WARNING
CAUTION
Safety 01 of 04 - 06/15/2016

SECTION A:
WARNINGS
CALIFORNIA PROPOSITION 65 WARNINGS
Diesel En ines
Diesel engine exhaust and some of its constituents are known
to the State of California to cause cancer, birth defects, and other
reproductive harm.
Gasoline En ines
The engine exhaust from this product contains chemicals known
to the State of California to cause cancer, birth defects, or other
reproductive harm.
ARC ELDING CAN BE HAZARDOUS. PROTECT
YOURSELF AND OTHERS FROM POSSIBLE SERIOUS
INJURY OR DEATH. KEEP CHILDREN A AY.
PACEMAKER EARERS SHOULD CONSULT ITH
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 incoln 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 pos-
sible to the area being welded.
2.d.5. Do not work next to welding power source.
SAFETY
Safety 02 of 04 - 06/15/2016

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 It ems 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. hen 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 PE and
ACGIH T V 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.
SAFETY
Safety 03 of 04 - 06/15/2016

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 undercarriage 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.
Refer to
http://www.lincolnelectric.com/safety
for additional safety information.
SAFETY
Safety 04 of 04 - 06/15/2016

iv
SAFETY
iv
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 suiv-
antes:
Sûreté Pour Soudage A LʼArc
1. Protegez-vous contre la secousse électrique:
a. Les circuits à lʼélectrode 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 sʼisoler 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 lʼeau 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 sʼapplicuent 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 nʼimporte quelle partie
du corps.
3. Un coup dʼarc peut être plus sévère quʼun coup de soliel,
donc:
a. Utiliser un bon masque avec un verre filtrant approprié
ainsi quʼun verre blanc afin de se protéger les yeux du ray-
onnement de lʼarc et des projections quand on soude ou
quand on regarde lʼarc.
b. Porter des vêtements convenables afin de protéger la
peau de soudeur et des aides contre le rayonnement de
lʻarc.
c. Protéger lʼautre personnel travaillant à proximité au
soudage à lʼaide dʼécrans appropriés et non-inflammables.
4. Des gouttes de laitier en fusion sont émises de lʼarc de
soudage. Se protéger avec des vêtements de protection libres
de lʼhuile, tels que les gants en cuir, chemise épaisse, pan-
talons 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 lʼon pique le laitier.
6. Eloigner les matériaux inflammables ou les recouvrir afin de
prévenir tout risque dʼincendie 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 dʼincendie.
8. Sʼassurer que la masse est connectée le plus prés possible
de la zone de travail quʼil est pratique de le faire. Si on place
la masse sur la charpente de la construction ou dʼautres
endroits éloignés de la zone de travail, on augmente le risque
de voir passer le courant de soudage par les chaines de lev-
age, câbles de grue, ou autres circuits. Cela peut provoquer
des risques dʼincendie ou dʼechauffement des chaines et des
câbles jusquʼà ce quʼils 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
dʼopérations de dégraissage, nettoyage ou pistolage. La
chaleur ou les rayons de lʼarc 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
TRANSFORMATEUR ET À
REDRESSEUR
1. Relier à la terre le chassis du poste conformement au code de
lʼélectricité et aux recommendations 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, Iʼinstallation et lʼentretien du poste seront
effectués par un électricien qualifié.
3. Avant de faires des travaux à lʼinterieur de poste, la debranch-
er à lʼinterrupteur à la boite de fusibles.
4. Garder tous les couvercles et dispositifs de sûreté à leur
place.

vi vi
TABLE OF CONTENTS
Page
Installation .......................................................................................................Section A
Location .................................................................................................................A-1
Input Wire ..............................................................................................................A-1
Output Connection ..........................................................................................A-1,A-2
________________________________________________________________________
Operation .........................................................................................................Section B
Safety Precautions ................................................................................................B-1
Duty Cycle .............................................................................................................B-1
Set Polarity .............................................................................................................B-1
Start the Welder ....................................................................................................B-1
Set for Machine or Remote Control.......................................................................B-1
Set the Welder Output...........................................................................................B-1
Mode Switch..........................................................................................................B-1
Set-up for Various Processes ........................................................................B-1, B-2
General Set-Up Procedures When Using DC-1500 and Lincoln Automatic Head NA-3 .......B-2, B-3
General Set-Up Procedures When Using DC-1500 and Lincoln Automatic Head NA-5 ..............B-4
Recommended Set-Up Procedures for NA-3/DC-1500, NA-5/DC-1500 ...............B-4
NL-Option Kit, Operation When Connected to the NA-2.......................................B-5
Operation When Connected to the LAF-3 and the K783 NL Option Kit ...............B-6
Operation When Connected to the LT-3 or LT-34 ................................................B-6
Overload Protection ..............................................................................................B-6
_______________________________________________________________________
Maintenance ....................................................................................................Section D
Safety Precaution ..................................................................................................D-1
General Maintenance ............................................................................................D-1
Overload Protection...............................................................................................D-1
________________________________________________________________________
Section E ..............................................................................................Troubleshooting
Safety Precautions.................................................................................................E-1
How to Use Troubleshooting Guide.......................................................................E-1
Troubleshooting Guide.............................................................................E-2 thru E-4
P.C. Board Troubleshooting Guide ................................................................E-3, E-4
________________________________________________________________________
Wiring Diagram, Connection Diagrams and Dimension Print .......................Section F
________________________________________________________________________
Parts List ........................................................................................P-118, P-84-J Series
________________________________________________________________________

A-1
INSTALLATION
IDEALARC®DC-1500
A-1
LOCATION
Install the welder in a dry location where there is free cir-cula-
tion of air in through the louvers in the front and out through
the louvers in the back of the case. A location which minimizes
the amount of smoke and dirt drawn into the machine
reduces the chance of dirt accumulation that can block air
passages and cause overheating.
INPUT WIRING
Failure to fuse the input lines per the specifications
in this manual will constitute customer abuse and
void the warranty.
-----------------------------------------------------------------------
Be sure the voltage, phase and frequency of the input power is
as specified on the welder nameplate.
Have a qualified electrician remove the lower right side case
panel and connect 3 phase AC power to terminals L1, L2and
L3of the input contactor in accordance with the Na-tional
Electrical Code, all local codes and the wiring diagram located
inside the machine.
The frame of the welder must be grounded. A stud marked
with the symbol located on the fan shroud is provided for
this purpose. See the U.S. National Electrical Code for
details on proper grounding methods.
Recommended Input Wire, Grounding Wire and
Fuse Sizes
Based on National Electrical Code For 60 Hertz,
3 Phase Welders at 100% Duty Cycle
NOTE: The standard machines are designed to oper-
ate on 460 volt-60 Hertz, 440 volt-50 Hertz and 380
volt-50 Hertz input power systems. However, to use
the machines on 380 volt-50 Hertz power, reconnect
the transformer input leads in accordance with the
connection diagram pasted to the inside of the lower
right side case panel.
OUTPUT CONNECTION
(Turn Power Source Off)
1. Output Studs
The “Positive” and “Negative” output studs are
located on the front panel. Two of each are provid-
ed to simplify connecting multiple electrode or
work cables as suggested in the table below.
Connect the electrode cables to the “Positive”
studs for electrode positive (DC+) polarity or to
the “Negative” stud for electrode negative (DC-)
polarity as required by the welding procedures.
Connect the work cables to the other set of studs.
Tighten the nuts with a wrench.
2. Auxiliary Power
This machine supplies the 1000 volt-amperes of
115 volt, AC power needed for the automatic wire
feeders. The power is available from terminals
#31 and #32 on the terminal strip.
3. “NL Option” (K783)
Installation of an NL option is required when con-
necting a DC-1500 to LAF-3, NA-2, LT-3 or LT-34
wire feeding systems. See the section on page 9
entitled “NL Option Kit” for full information.
4. Wire Feeder Connection — Without NL Option
Turn the welder off. Remove the screw and lift the
hinged door on the front of the control panel to
expose the terminal strips. Connect the leads of
the wire feeder input control cable to the terminal
strip exactly as spec-ified in the appropriate con-
nection diagram included in the wire feeder
Operating Manual. Attach the control cable to the
panel at the right of the terminal strip using the
clamp attached to the control cable. Close the
door and replace the screw.
To connect the DC-1500 to wire feeders not cov-
ered in available connection diagrams, write to
the factory for instructions giving complete name-
plate information for the DC-1500 and wire feed-
er.
Copper Wire Size
Type 75° In Conduit
Input Amps 3 Input Grounding Super Lag Fuse
Volts Input Wires Conductor Size in Amps
460 184 000 3 300
Suggested Copper Cable Sizes — 80% Duty Cycle
Below 1000 amps Two 4/0
1000 to 1200 amps Three 4/0 Up to
1200 to 1500 amps Four 4/0 200’
WARNING
FALLING
EQUIPMENT can
cause injury.
• Do not lift this machine using lift
bale if it is equipped with a
heavy accessory such as a trailer
or gas cylinder.
• Lift only with equipment of
adequate lifting capacity.
• Be sure machine is stable when
lifting.
WARNING
ELECTRIC SHOCK
can kill.
• Have an electrician install and
service this equipment.
• Turn the input power off at the
fuse box before working on
equipment.
• Do not touch electrically hot
parts.

A-2
INSTALLATION
IDEALARC®DC-1500
A-2
5. Optional Remote Control (K775)
This control is included as part of the “NL Option”.
Connect it to the “NL Option” box per instructions
shipped with the option. (Not required with the NA-
3, NA-5, LT-7 or LT-56.)
It can be purchased separately when the DC-1500
is used for other applications.
To install, turn the power off. Remove the screw
and lift the hinged door on the front of the control
panel to expose the terminal strips. Connect the
numbered leads to the appropriate terminals — 75
to 75, etc — on the terminal strip and the green
lead to the stud marked with the symbol .
Attach the control cord to the panel at the right of
the terminal strip using a suitable clamp. Close the
door and replace the screw. The Re-mote Control
cord can be lengthened to any length by properly
splicing an appropriate four conductor rubber-cov-
ered cable to the standard 25’ cord before connect-
ing to the DC-1500 terminal strip.
6. Connecting for Air Carbon Arc
To use the DC-1500 for air carbon arc or other
appli-cations, disconnect all wire feeder welding
cables and control leads and connect a jumper
between #2 and #4 on the terminal strip on the front
of the DC-1500. With the #2 to #4 jumper connect-
ed, the output studs are en-ergized whenever the
machine is on.
If the electrode leads to the wire are not discon-
nected per instructions, the wire feeder nozzle or gun
and electrode will be electrically “hot”.
---------------------------------------------------------------
7. DC-1500 Paralleling Kit
A kit for field installation only, (order K1900-1) is
avail-able for paralleling two DC-1500’s for currents
up to 3000 amperes, 100% duty cycle. Complete
installation instructions are shipped with the kit.
8. Connecting for High Frequency Starting
As shipped, these welders can be used with a high
frequency unit for improved automatic welding start-
ing characteristics.
RATINGS
IP21 enclosure
Main Transformer insulation class 155° (F)
WARNING

B-1
OPERATION
B-1
IDEALARC®DC-1500
DUTY CYCLE
The DC-1500 is rated for 100% duty cycle at 1500 amps
and 60 volts.
SET POLARITY
Connect the electrode cable to the “Positive” or “Negative”
studs depending upon the electrode polarity desired.
Connect the work cable to the other studs.
Set the “Electrode Negative — Electrode Positive” switch
to correspond to the polarity of the electrode cable connec-
tion. This switch setting is necessary for proper operation
of the Lincoln wire feeder attached to the power source.
START THE WELDER
Press the “ On - Off ” pushbuttons to start and stop the
welder. The red pilot light near the center of the control
panel indicates when the welder is on.
SET FOR MACHINE OR REMOTE CONTROL
The output can be controlled either at the wire feeder
or the DC-1500. When the NL Option Kit is installed,
the output is controlled only from the K775 Remote
Control usually mounted at the wire feeder.
To adjust the output from the wire feeder, set the tog-
gle switch on the front of the DC-1500 to “Output
Control Remote”. To adjust the output using the DC-
1500 “Output Control” rheostat, set this switch to
“Output Control at DC-1500”.
SET THE WELDER OUTPUT
With the toggle switch set to “Output Control at DC-
1500”, rotating the “Output Control” rheostat on the
DC-1500 from 1 to 10 increases the machine output
from minimum to maximum. The same full range con-
trol is set from the wire feeder or K775 when the toggle
switch is set to “Output Control Remote”.
Set the output as required by the welding procedures.
MODE SWITCH
The toggle switch labeled CV Innershield, CV sub-
merged arc, VV submerged arc, is used to select the
proper welder characteristics for the process being
used.
NOTE: Some machines say ”VV” for variable voltage
while other machines use the terminology “CC” for
constant current.
The CV Innershield Mode permits the DC-1500 to pro-
duce essentially a flat output characteristic that can be
varied from approximately 20 to 60 volts. In this posi-
tion the dynamic characteristics of the machine under
welding conditions provides optimum welding charac-
teristics for Innershield welding and other open arc
processes.
The CV Submerged Arc Mode also produces an
essentially flat output characteristics that can be var-
ied from approximately 20 to 60 volts. The dynamic
characteristics of the CV Submerged Arc Mode are
such that excellent submerged arc welding can be
obtained for most procedures that previously required
a constant current type power source.
The VV Submerged Arc Mode permits the DC-1500 to
produce a constant current output characteristic
through the range of 200A-28V to 1500A-60V with an
open circuit voltage of 45 to 98 volts. Although almost
all submerged arc welding can now be done in the CV
mode, the VV mode is available for those procedures
where VV (CC) may still be desirable.
Set-up for Various Processes
Selection of mode switch position — There are sever-
al general rules to follow in the selection of the mode
switch position.
1. Use the CV Innershield mode for all Innershield
welding.
ELECTRIC SHOCK
can kill.
• Do not touch electrically live
parts or electrode with skin or
wet clothing.
• Insulate yourself from work
and ground.
ARC RAYS
can burn.
• Wear eye, ear and body protec-
tion.
WELDING SPARKS
can cause fire or
explosion.
• Keep flammable material
away.
FUMES AND
GASES can be
dangerous.
• Keep your head out of fumes.
• Use ventilation or exhaust to
remove fumes from breath-
ing zone.
WARNING
SAFETY PRECAUTIONS

B-2
OPERATION
B-2
IDEALARC®DC-1500
Approximate Voltage Voltage Control Setting
22-24 2
34-36 4
46-48 6
56-60 8
2. Use the CV Submerged Arc mode for most sub-
merged arc welding. However, some high speed
welding procedures may perform better on the CV
Innershield mode.
3. The VV (CC) mode is available for high current,
large puddle submerged arc procedures that can-
not be done as well with the constant voltage
mode.
4. Air Carbon Arc Gouging or Cutting — For air
carbon arc gouging, the constant voltage
Innershield mode is used with the output control
set between 4 and max. depending on the applica-
tion, carbon size, etc. Up to 1/2” carbons, start with
the machine control set at 4 and increase as
required for long cable lengths. With 1/2” and 5/8”
carbons, short (100’) cable lengths can lead to
occasional trip out of the protection circuit when the
carbon is shorted to the work. Cutting back the out-
put setting will reduce the short circuit current and
minimize tripping. Longer cable lengths do an even
better job since this also reduces the short circuit
current but even more significantly permits raising
the open circuit voltage (by increasing control set-
ting) for smoother operation. See the table below
for optimum cable size and length.
TABLE B.1
If ever longer leads are used and the output control
is already set on max., the unit has reached its
maximum air carbon arc capability.
3/4” carbons are not recommended for use with the
DC-1500 because the high surge currents that
occur with this diameter can cause the DC-1500
fault protection circuitry to trip the machine off the
line, if the operator does not gouge in such a way
to limit the currents.
General Set-Up Procedures When Using DC-1500
and Lincoln Automatic Head NA-3
(Read the following and refer to Table B.3 in the
Operation Section.)
1. NA-3 — The NA-3 should be set for the mode
being used on the power source. If using either of
the CV modes, the NA-3 VV board switch should
be set for CV. If the power source is used in the VV
mode, then the NA-3 VV board mode switch should
be placed in the VV position.
All NA-3’s when used with the DC-1500 are capa-
ble of cold starting with the variable voltage board
mode switch in VV. Cold starting permits the wire
to be inches down to the work, automatically stop
and automatically energize the flux hopper valve.
All NA-3’s made after September 1976, are capable
of cold starting on either CV or VV settings of the
variable voltage board switch.
2. Arc striking with DC-1500 mode switch on CV
sub-arc or CV Innershield — There are a number
of basic techniques for good arc striking that apply
to all processes and power sources. It may not be
necessary in every application to follow these
guidelines, but when striking problems do occur,
following the suggestions below should provide
trouble-free starting. These procedures apply to all
single solid wire, Innershield wire, and Twinarc 1/8”
and 3/32” solid wire.
• Except for long stickout Innershield procedures
and Tiny Twinarc 1/16” procedures, an NA-3 start
board is not needed. If a start board is not need-
ed, it should be removed from the machine, or at
least disconnected and the logic board jumper
plug replaced. Leaving it connected makes the
setup for arc striking more difficult. Also, if a crater
board is not needed, it should be removed from
the NA-3 or at least electrically disconnected and
the jumper plug replaced.
• Cut electrode to a sharp point.
• For cold starts, make certain work piece is clean
and electrode makes positive contact with plate.
• For hot starts, travel should be started before wire
contacts the work (“on the fly” starting).
• Set NA-3 open circuit voltage control to approxi-
mately the same setting as the weld setting. For
initial test welds, choose the voltage setting
based on the Table B.2. Set the inch control to 2.
These are approximate settings only until the
welding procedure has been set.
It should be noted that with the DC-1500 the OCV
required for optimum starting is lower than that
required with other type power sources.
TABLE B.2
• Run a test weld, setting the proper current, volt-
age and travel speed.
Combined Total
Electrode and Electrode
Carbon Typical Work Lead Length and Work
Size Current Range (Min) (Max) Lead Size
1/2” 600-1000 Amps 250’ 825’ 2 — 4/0
5/8” 800-1200 Amps 375’ 925’ 3 — 4/0

B-3
OPERATION
B-3
IDEALARC®DC-1500
• Once the proper welding procedure is established
and if the start is poor — wire blast-off, stub, etc.,
adjust the OCV and inch speed for optimum start-
ing. In general, a low inch speed will provide the
best starting.
Adjust the OCV by making repeated starts and
observing the voltmeter action.
With proper adjustment of the OCV control, the
voltmeter needle will swing smoothly up to the de-
sired arc voltage and thus provide repeatable
starts.
If the voltmeter swings above then back to the de-
sired welding voltage, the OCV setting is too high.
This usually results in a bad start where the wire
tends to “blast-off”.
If the voltmeter needle hesitates before coming up
to the desired voltage, the OCV is set too low.
This will cause the electrode to stub.
• For Twinarc welding, clipping both wires to equal
lengths will be beneficial to make consistently
good starts.
3. Single Innershield Wire — Procedures and tech-
niques are the same as above, except starting is
generally better “hot” than “cold”. For electrical
stickouts above 1 3/4” an NA-3 start board is
required.
4. Twinarc Innershield — Procedures and tech-
niques are the same as above, except starting is
generally better “hot than “cold”. Use of an NA-3
start board improves starting.
5. Twinarc Submerged Arc 1/16” — Procedures
and techniques are the same as above, except start-
ing is best when using CV Innershield and the NA-3
start board.
6. Use of the NA-3 Start Board — For those
processes above that recommend use of the NA-3
start board, the following method should be used to
set up the procedure.
• Set start time at 0 and start current and voltage at
mid-range. Start the weld and set the proper cur-
rent and voltage for the welding procedure.
• Turn the start board timer to maximum.
• Set start board current 1 to 1 1/2” dial numbers
below NA-3 front control settings.
• Place start board’s voltage control approximately
equal to NA-3 voltage control setting.
When set per c and d, above, the starting only
procedure will provide a current setting lower than
the NA-3 current setting and a voltage setting
nearly equal to the desired welding procedure.
• With the start board time delay set at maximum,
establish the correct arc striking procedure as de-
scribed previously by changing OCV and inch
speed.
• Now increase the start board current and voltage
to bring the start current and voltage closer to the
welding procedure. The start board current and
voltage should be as close to the welding proce-
dure as possible while still getting satisfactory
starts.
• Now decrease the start time as low as possible
for optimum starts.
7. Arc striking with the DC-1500 mode switch in VV.
•NA-3 — The NA-3 variable voltage board mode
switch should be set to the VV position.
• Set OCV control at 6.5 to 7.0.
• Other techniques recommended in the previous
sections for good arc striking apply here also.

B-4
OPERATION
B-4
IDEALARC®DC-1500
INNERSHIELD SUBMERGED ARC
Single Single
Innershield Innershield High Current
Equipment and Stickout Stickout Twinarc Single Tiny Twin Very Large
Control Settings under 1 3/4” over 1 3/4” Innershield Solid Wire
Tiny Twin 1/16”
(1) Over 1/16” Puddle
Wire Feed Type NA-3S NA-3S NA-3S
Control or NA-5 or NA-5 or NA-5 NA-3S NA-5 NA-3S NA-5 NA-3S NA-5 NA-3S NA-5
NA-3N NA-3N NA-3N
NA-3S VV Board
Mode Switch CV — CV — CV — CV — CV — CV — VV —
NA-3 Inch Speed
Dial Setting (5) 2—2—2—2— 2—2— 2—
NA-5 Arc Striking — (4) —(4) —(4) —(4) —(4) —(4) —(4)
Wire Speed (5)
NA-3 OCV Control
(5) (6) —(6) —(6) —(6) —(6) —(6) — 6.5 - 7.0 —
NA-5 Arc Striking (4) (4) (4) (4) (4) (4) (4)
Volts Control —— — — — — —
NA-3 Start Board (2) — Req’d (2) — Req’d (2) —(2) —(2) —(2) —(2) —
DC-1500 Output
Control Switch — Remote Remote Remote Remote Remote Remote Remote
Machine or Remote
DC-1500 CV CV CV CV Submerged CV CV Submerged NA-3S NA-5
Mode Innershield Innershield Innershield Arc (3) Innershield Arc (3)
CC CVS
Switch
DC-1500 Output Inoperative Inoperative Inoperative Inoperative Inoperative Inoperative Inoperative
Control
For initial test welds, set the NA-5 arc striking
wire speed control to 1/2 the weld wire feed
speed and the arc striking voltage control 4
volts above the weld voltage.
• If striking is still not satisfactory, see the NA-5
operating manual for information on the feed
motor acceleration.
• If installed, adjust the “Start Controls” to set the
welding procedures for the time set on the timer
to provide the bead size, penetration, or other
factor as needed for the application. If not used,
this board should be disconnected and the
jumper plug replaced.
• If installed, adjust the “Crater Controls” to set
the welding procedures for the set time after the
stop button is pressed to provide the bead size
or fill the crater as needed for the application. If
not used, this board should be disconnected
and the jumper plug replaced.
• Set the “Burnback Time” to provide the stopping
characteristics needed.
General Set-Up Procedures When Using DC-1500 and
Lincoln Automatic Head NA-5
(See Table B.3)
1. Install the NA-5 per the information in the NA-5 oper-
ating manual (IM-305). Connect the NA-5 to the DC-
1500 as described on the connection diagram.
2. Place the DC-1500 mode switch in the proper position
according to the process and procedure to be used.
3. Place the machine/remote switch in remote.
4. Connect the work lead to the work or a suitable piece
of scrap. Clip the end of the electrode to a sharp
point.
5. Preset the Start (if used), Weld and Crater (if used)
Controls to the wire speed and voltage specified in
the procedure.
6. Make several test welds, readjusting the starting and
stopping controls in the following order:
• Set the Arc Striking Wire Speed and Volts Controls
for optimum arc striking.
RECOMMENDED SET-UP PROCEDURES FOR NA-3/DC-1500, NA-5/DC-1500
(1) Starting is best with “hot” starting. Start button is pressed with wire above the work.
(2) If an Na-3 start board is called for, refer to (General Set-Up Procedures When Using DC-1500 and Lincoln Automatic Head NA-3
in this Operation Section) for details on how to set the controls. If an NA-3 start board is not required, it should be electrically discon-
nected and the jumper plug replaced.
(3) Some high speed welding procedures may perform better on the CV Innershield mode. Merely change the switch between CV Innershield
and CV Submerged arc position and select the best welding.
(4) The NA-5 arc striking wire speed should initially be set at 1/2 the welding wire feed speed, and the NA-5 arc striking volts control 4
volts above the welding voltage. These controls can be adjusted as required for optimum arc striking.
(5) Exact dial setting depends on cable size and length, carbon size, etc.
(6) Set the OCV control to the same dial setting as the NA-3 voltage control. For initial test welds, choose the setting on Table B.1 in this
Operation Section.
TABLE B.3

B-5
OPERATION
B-5
IDEALARC®DC-1500
NL Option Kit
(Not Required With NA-3, NA-5, LT-7 or LT-56)
The K783 NL option kit (for field installation) is
designed to permit use of the NA-2, LAF-3, LT-3 and
the LT-3 section of the LT-34 tractor with DC-1500’s
assigned code 7687 and above. It provides the neces-
sary DC control power for the operation of the equip-
ment and the necessary circuitry for proper inching,
cold starting and arc striking. In using the NL option
kit a K775 remote field control is required and is
included as part of the option kit. (See Item 5 in the
Installation Section)
The NL option kit consists of a sheet metal box, 12.5”
long, 11.5” deep and 5.7” high. This box mounts on
top of the DC-1500 and the following controls are
located on the front of the box:
1. Inch speed control — used for LT tractor only.
2. Hot start control — used to obtain optimum arc
striking.
3. Polarity switch — changes polarity of control cir-
cuit to correspond with electrode polarity.
4. Contactor dropout delay switch — switches in or
out a slight contactor drop out delay to prevent
sticking of the wire in the crater at the end of weld-
ing.
The terminal strip for connection to the automatic
equipment is located under the front cover. All neces-
sary control leads for connection to the DC-1500 are
wired into the NL kit for easy connection to the DC-
1500 terminal strip.
Before proceeding with any installation, be certain
the DC-1500 is turned off.
-------------------------------------------------------------
1. Mount the NL option box to the top of the DC-1500
with the screws used to fasten the roof and sides.
2. Remove the cover of the NL option for access to
the terminal strip.
3. Feed the control cable from the automatic wire
feed control unit through the grommet on the front
of the NL box. Connect the control leads per the
appropriate Connection Diagram Section at the
back of this manual. Secure the cables to the case
with the clamps and screws provided.
4. Using the same diagram, connect the leads from
the option kit to the DC-1500 terminal strip.
5. Feed the K775 control cable through the clamp on
the front of the NL option box and connect the
leads to terminals 75,76, and 77 per connection
diagram.
6. Replace the cover. This completes the installation.
NOTE: An NL Option was factory installed inside
DC-1500’s built to codes 7562-NL, 7636-NL and
7676-NL. The instructions for the K783 apply except
as follows:
1. The factory installed NL Option does not have a
separate “POS — NEG” switch.
2. The factory installed NL Option does not have an
“Inch Speed” control.
3. It cannot be used with LT-3 or LT-34 wire feeders.
4. The fuse protecting the 115 volt DC circuit is a 2
amp fuse located on the NL Option panel inside the
welder.
Operation When Connected to the NA-2
1. Set the “POS — NEG” switch (on both NL Option &
DC-1500) to correspond to the polarity of the elec-
trode cable connection.
2. Set the mode switch on the front of the DC-15000
to “Constant Voltage — Innershield” or “Constant
Voltage — Sumerged Arc”.
3. Set the toggle switch on the front of the DC-1500 to
“Output Control Remote”.
4. Set the output as required for the procedures using
the K775 Remote Output Control shipped with the
NL Option.
5. Set the NA-2 inch speed to a speed lower than
welding feed speed for good starting using the con-
trol on the NA-2. The NL Option “Inch Speed” con-
trol is not in the circuit.
6. Set the “Hot Start Control” on the NL Option to 4.
7. Set the “Contactor Drop-Out Delay” switch to “Off”.
Refer to the NA-2 Operating Manual for instruc-
tions for setting the contactor drop-out delay and
crater fill-ing features built into the NA-2 circuit.
WARNING

B-6
OPERATION
B-6
Operation When Connected to the LAF-3
and the K783 NL Option Kit
For proper arc striking and welding when using the
LAF-3 with the DC-1500 and K783 NL Option Kit, fol-
low the instructions below (Turn the input power off at
the fuse box before working inside the machine.):
1. Connect the DC-1500 NL option, and LAF-3 per
the Connection Diagram M13321 in the Diagram
Section.
2. Remove the cover from the LAF-3 control box.
3. Remove the blue jumper lead connected between
#1 on the coil of the main relay and #7 on the coil
of the transfer relay. (The main relay is the upper
right relay when facing the left end of the control
box. The transfer relay is just to the left of the main
relay.)
4. Replace the LAF-3 control cover.
5. Set the “POS — NEG” switch (on both the NL
Option and the DC-1500) to correspond to the
polarity of the electrode cable connection.
6. Set the mode switch on the front of the DC-1500 to
“Variable Voltage”.
7. Set the toggle switch on the front of the DC-1500 to
“Output Control Remote”.
8. Set the DC-1500 welding current as required by
the procedures using the K775 Remote Output
Control shipped with the NL Option.
9. Set the LAF-3 “Inch Speed” control near minimum
so the electrode touches the work lightly before
starting the arc. The NL Option “Inch Speed” con-
trol is not in the circuit.
10. Set the “Hot Start Control” on the NL Option at
#2. This setting does not change the open cir-
cuit voltage, but it will improve starting, particu-
larly at low currents. Adjust the control for opti-
mum starting.
NOTE: The “Hot Start Control” does not affect the
starting method of the LAF-3, i.e., “cold” start, “hot”
start, etc. See IM198-B, Sec. 2.4.9.
11. Set the NL Option “Contactor Drop-Out Delay”
switch to “On”. This circuit delays opening of
the output contactor for a fixed length of time
after wire feeding stops to prevent sticking.
Operation When Connected to the LT-3 or
LT-34
Follow the same instructions as above except in Step
1, connect per M13322. Omit Steps 2, 3 and 4. Set
the “Inch Speed” control on the NL Option as low as
possible so the electrode touches the work piece light-
ly before starting the arc.
Overload Protection
The NL Option kit includes two fuses on the front
panel. The upper fuse (2 amp slow blow) protects the
inching circuit when the option is used with LT-3 and
LT-34 wire feeders. The lower fuse (2.8 amp slow
blow) protects the 115 volt DC circuit (#1 and #2). If
replacing either fuse use the same size and type.
IDEALARC®DC-1500

D-1
MAINTENANCE
D-1
IDEALARC®DC-1500
GENERAL MAINTENANCE
1. The fan motors have sealed bearings which require
no service.
2. In extremely dusty locations, dirt may clog the air
channels causing the welder to run hot. Blow out
the welder with low pressure air at regular inter-
vals. Also blow dirt out of the NL Option box.
OVERLOAD PROTECTION
The DC-1500 has built-in protective thermostats. If the
rectifier or transformer reaches the maximum safe
operating temperature because of frequent overload or
high room temperature plus overload, the contactor
drops out stopping the welder. The thermostat auto-
matically reset when the temperature reaches a safe
operating level. Press the “On” button to start the
welder.
The power rectifiers are also protected by a special
solid state circuit. With the occurrence of a short cir-
cuit or excessively high overloads, the input contactor
opens. When the overload is removed, press the “On”
button to start the welder.
An 8 amp slow blow fuse located on the front of the
machine protects the 115 volt auxiliary AC circuit (#31
and #32) from overload. If replacing, use the same
type and size fuse.
• Have an electrician install and
service this equipment.
• Turn the input power off at the
fuse box before working on
equipment.
• Do not touch electrically hot parts.
ELECTRIC SHOCK
can kill.
WARNING

E-1
TROUBLESHOOTING
E-1
IDEALARC®DC-1500
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
This Troubleshooting Guide is provided to help you
locate and repair possible machine malfunctions.
Simply follow the three-step procedure listed below.
Step 1. LOCATE PROBLEM (SYMPTOM).
Look under the column labeled “PROBLEM (SYMP-
TOMS)”. This column describes possible symptoms
that the machine may exhibit. Find the listing that
best describes the symptom that the machine is
exhibiting.
Step 2. POSSIBLE CAUSE.
The second column labeled “POSSIBLE CAUSE” lists
the obvious external possibilities that may contribute
to the machine symptom.
Step 3. RECOMMENDED COURSE OF ACTION
This column provides a course of action for the
Possible Cause, generally it states to contact your
local Lincoln Authorized Field Service Facility.
If you do not understand or are unable to perform the
Recommended Course of Action safely, contact your
local Lincoln Authorized Field Service Facility.
HOW TO USE TROUBLESHOOTING GUIDE
Service and Repair should only be performed by Lincoln Electric Factory Trained Personnel.
Unauthorized repairs performed on this equipment may result in danger to the technician and
machine operator and will invalidate your factory warranty. For your safety and to avoid Electrical
Shock, please observe all safety notes and precautions detailed throughout this manual.
__________________________________________________________________________
WARNING
Note: To locate the “Firing Circuit” and “Control/Fault Protection Circuit” P.C. boards, remove the upper case
panel on the left side of the machine. The names are printed on the boards.

E-2
TROUBLESHOOTING
E-2
IDEALARC®DC-1500
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
Input contactor (CR1) chatters.
Machine input contactor does not
operate.
Machine input contactor operates
but no output when trying to weld.
Machine has maximum output but no
control.
1. Faulty input contactor (1CR).
2. Low line voltage.
3. Faulty pilot relay (2CR).
1. Supply line fuse blown.
2. Contactor power circuit dead.
3. Broken power lead.
4. Wrong input voltage.
5. Primary or power SCR ther-
mostats open.
6. Open input contactor coil.
7. Faulty on-off switch.
8. Faulty pilot relay (2CR).
1. Electrode or work lead loose or
broken.
2. Open main transformer (T5) pri-
mary or secondary circuit.
3. “Firing Circuit” P.C. board not
connected or is faulty.
4. Output pilot relay (6CR) not oper-
ating or faulty.
1. “Output Control” switch (SW4) in
wrong position.
2. “Output Control” switch faulty.
3. Open in feed back circuitry.
4. Faulty “Control/Fault Protection”
or “Firing Circuit” P.C. boards.
5. Output control potentiometer
open (lead no. 75).
1. Repair or replace.
2. Check with power company.
3. Replace relay.
1. Replace if blown. Look for rea-
son first.
2. Check pilot transformer T1 and
associated leads and 5 amp fuse.
3. Check input voltage at contactor.
4. Check voltage against name-
plate.
5. Check for overheating. Make
sure both fans are operating and
there is no obstruction to free air
flow. Faulty thermostats —
replace.
6. Replace coil.
7. Replace switch.
8. Replace relay.
1. Repair connection.
2. Repair.
3. All nine light emitting diodes (L1
thru L9) must be lit. (See “P.C.
Board Troubleshooting Guide”.)
4. Check relay by connecting a
jumper across terminals 2 and 4
on DC-1500 terminal strip.
Replace if faulty.
1. Check position of switch.
2. Check switch and replace if
faulty.
3. Check wiring and control and
“Firing Circuit” P.C. board wiring
harness plugs.
4. All light emitting diodes must be
lit, except L4 on “Control/Fault
Protection” board. (See “P.C.
Board Troubleshooting Guide.”)
5. Check and replace if faulty.

E-3
TROUBLESHOOTING
E-3
IDEALARC®DC-1500
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
Machine does not have maximum
output.
Machine has output but trips off
immediately.
Variable or sluggish welding arc.
Machine will not shut off.
1. One input fuse blown.
2. One phase of main transformer
open.
3. Faulty “Control/Fault Protection”
or “Firing Circuit” P.C. boards.
4. Output control potentiometer
defective.
5. Output control potentiometer
leads open 226, 237, 236, 73, 74,
76, 77.
1. Machine has either an internal or
external short circuit on the out-
put.
2. Faulty “Control/Fault Protection”
P.C. board.
3. Machine output voltage applied to
control leads.
1. Poor work or electrode connec-
tion.
2. Welding Cables too small.
3. Welding current or voltage too
low.
1. Input contacts frozen.
2. Pilot relay contacts stuck closed.
1. Check and replace if blown after
checking for reason for blown
fuse.
2. Check for open and repair.
3. All light emitting diodes must be lit
on both P.C. boards, except L4
on “Control/Fault Protection”
board.(See “P.C. Board
Troubleshooting Guide.”)
4. Check and replace if faulty.
5. Check and repair broken leads.
1. Check internally and externally for
any shorts and remove or repair.
2. If no short circuits, LED L4 must
be lit (See “P.C. Board
Troubleshooting Guide”).
3. Check control cable or wire feed-
er for shorted or grounded control
leads.
1. Check and clean all connections.
2. Check Suggested Copper Cable
Sizes in the table of the Instalation
Section.
3. Check procedures for recommend-
ed settings.
1. Check for approximately .13 inch
over travel of contacts.
2. Check and replace if necessary.

E-4
TROUBLESHOOTING
E-4
IDEALARC®DC-1500
Observe all Safety Guidelines detailed throughout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your
Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
Output control not functioning on the
machine.
Output control not functioning on the
machine.
Machine trips off with High
Current Procedures on starting.
1. “Output Control” switch in the
wrong position.
2. Faulty output control switch.
3. Faulty “Output Control” rheostat.
4. Leads or connections open in
“Control Circuit”.
5. Faulty “Firing Circuit” or
“Control/Fault Protection” P.C.
board.
1. “Output Control” switch in the
wrong position.
2. Faulty output control switch.
3. Faulty remote control rheostat.
4. Leads or connections open in
“Control Circuit”
5. Faulty “Firing” or “Control/Fault
Protection” P.C. board.
1. OCV setting too high.
2. Defective control board.
1. Place switch in “Output Control at
DC-1500”.
2. Check and replace if found faulty.
3. Check and replace if found faulty.
4. Check lead continuity and connec-
tions for an open and repair if nec-
essary.
5. All light emitting diodes must be lit
on both P.C. boards, except L4
on “Control/Fault Protection”
board. (See “P.C. Board
Troubleshooting Guide.”)
1. Place switch in “Output Control
Remote”.
2. Check and replace if found faulty.
3. Check and replace if found faulty.
4. Check all leads and connections,
internal and remote, for continuity
and repair if necessary.
5. All light emitting diodes must be lit
on both P.C. boards, except L4
on “Control/Fault Protection”
board. (See “P.C. Board
Troubleshooting Guide.”)
1. Reduce OCV setting.
2. Replace control board.