Lincoln Electric IM10107 User Manual

IDEALARC

11829, 11831, 11832, 11833, 11834

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®

DC-400

IM10107

October, 2011

For use with machines having Code Numbers:

Safety Depends on You

Lincoln 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.

Cleveland, Ohio 44117-1199 U.S.A. TEL: [phone] FAX: [phone] WEB SITE: www.lincolnelectric.com

OPERATORʼS MANUAL

Copyright © Lincoln Global Inc.

• World's Leader in Welding and Cutting Products •

• Sales and Service through Subsidiaries and Distributors Worldwide •

i

SAFETY

i

WARNING

CALIFORNIA PROPOSITION 65 WARNINGS

Diesel engine exhaust and some of its constituents
are known to the State of California to cause can­cer, birth defects, and other reproductive harm.

The Above For Diesel Engines

ARC WELDING CAN BE HAZARDOUS. PROTECT YOURSELF AND OTHERS FROM POSSIBLE SERIOUS INJURY OR DEATH.
KEEP CHILDREN AWAY. PACEMAKER WEARERS SHOULD CONSULT WITH THEIR DOCTOR BEFORE OPERATING.

Read and understand the following safety highlights. For additional safety information, it is strongly recommended that you
purchase a copy of “Safety in Welding & Cutting - ANSI Standard Z49.1” from the American Welding Society, P.O. Box
351040, Miami, Florida 33135 or CSA Standard W117.2-1974. A Free copy of “Arc Welding Safety” booklet E205 is available
from the Lincoln Electric Company, 22801 St. Clair Avenue, Cleveland, Ohio 44117-1199.

BE SURE THAT ALL INSTALLATION, OPERATION, MAINTENANCE AND REPAIR PROCEDURES ARE
PERFORMED ONLY BY QUALIFIED INDIVIDUALS.

The engine exhaust from this product contains
chemicals known to the State of California to cause
cancer, birth defects, or other reproductive harm.

The Above For Gasoline Engines

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.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.

___________________________________________________

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.

2.d.4. Connect the work cable to the workpiece as close as
possible to the area being welded.

2.d.5. Do not work next to welding power source.

ii

SAFETY

ii

ELECTRIC SHOCK can
kill.

3.a. The electrode and work (or ground) circuits
are electrically “hot” when the welder is on.
Do not touch these “hot” parts with your bare
skin or wet clothing. Wear dry, hole-free

gloves to insulate hands.

3.b. Insulate yourself from work and ground using dry insulation.
Make certain the insulation is large enough to cover your full
area of physical contact with work and ground.

In addition to the normal safety precautions, if welding
must be performed under electrically hazardous
conditions (in damp locations or while wearing wet
clothing; on metal structures such as floors, gratings or
scaffolds; when in cramped positions such as sitting,
kneeling or lying, if there is a high risk of unavoidable or
accidental contact with the workpiece or ground) use
the following equipment:

• Semiautomatic DC Constant Voltage (Wire) Welder.

• DC Manual (Stick) Welder.

• AC Welder with Reduced Voltage Control.

3.c. In semiautomatic or automatic wire welding, the electrode,
electrode reel, welding head, nozzle or semiautomatic
welding gun are also electrically “hot”.

3.d. Always be sure the work cable makes a good electrical
connection with the metal being welded. The connection
should be as close as possible to the area being welded.

3.e. Ground the work or metal to be welded to a good electrical
(earth) ground.

3.f.

Maintain the electrode holder, work clamp, welding cable and
welding machine in good, safe operating condition. Replace
damaged insulation.

3.g. Never dip the electrode in water for cooling.

3.h. Never simultaneously touch electrically “hot” parts of
electrode holders connected to two welders because voltage
between the two can be the total of the open circuit voltage
of both welders.

3.i. When working above floor level, use a safety belt to protect
yourself from a fall should you get a shock.

3.j. Also see Items 6.c. and 8.

ARC RAYS can burn.

4.a. Use a shield with the proper filter and cover
plates to protect your eyes from sparks and
the rays of the arc when welding or observing
open arc welding. Headshield and filter lens
should conform to ANSI Z87. I standards.

4.b. Use suitable clothing made from durable flame-resistant
material to protect your skin and that of your helpers from
the arc rays.

4.c. Protect other nearby personnel with suitable, non-flammable
screening and/or warn them not to watch the arc nor expose
themselves to the arc rays or to hot spatter or metal.

FUMES AND GASES
can be dangerous.

5.a. Welding may produce fumes and gases
hazardous to health. Avoid breathing these
fumes and gases. When welding, keep
your head out of the fume. Use enough
ventilation and/or exhaust at the arc to keep

fumes and gases away from the breathing zone. When

welding with electrodes which require special
ventilation such as stainless or hard facing (see
instructions on container or MSDS) 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. In confined spaces or in some circum­stances, outdoors, a respirator may be required.
Additional precautions are also required when welding
on galvanized steel.

5. b. The operation of welding fume control equipment is affected
by various factors including proper use and positioning of
the equipment, maintenance of the equipment and the spe­cific welding procedure and application involved. Worker
exposure level should be checked upon installation and
periodically thereafter to be certain it is within applicable
OSHA PEL and ACGIH TLV limits.

5.c.

Do not weld in locations near chlorinated hydrocarbon
coming from degreasing, cleaning or spraying operations.
The heat and rays of the arc can react with solvent vapors
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.

vapors

to

5.e. Read and understand the manufacturer’s instructions for this

equipment and the consumables to be used, including the
material safety data sheet (MSDS) and follow your
employer’s safety practices. MSDS forms are available from
your welding distributor or from the manufacturer.

5.f. Also see item 1.b.

iii

SAFETY

iii

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

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
been “cleaned”. For information, purchase “Recommended
Safe Practices for the
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.

Sparks and spatter are thrown from the welding arc. Wear oil

6.f.
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.

the welding sparks from starting a fire.

though

they have

Preparation

for Welding and Cutting of

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
1235 Jefferson Davis Highway, Arlington, VA 22202.

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.

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.

Refer to http://www.lincolnelectric.com/safety for additional safety information.

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 suiv­antes:

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.

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 lev­age, 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

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 ray­onnement 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, pan­talons sans revers, et chaussures montantes.

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 debranch­er à lʼinterrupteur à la boite de fusibles.

4. Garder tous les couvercles et dispositifs de sûreté à leur
place.

Thank You

vv

for selecting a QUALITY product by Lincoln Electric. We want you
to take pride in operating this Lincoln Electric Company product

••• as much pride as we have in bringing this product to you!

The business of The Lincoln Electric Company is manufacturing and selling high quality welding equipment, consumables, and cutting equip­ment. Our challenge is to meet the needs of our customers and to exceed their expectations. On occasion, purchasers may ask Lincoln
Electric for advice or information about their use of our products. We respond to our customers based on the best information in our posses­sion at that time. Lincoln Electric is not in a position to warrant or guarantee such advice, and assumes no liability, with respect to such infor­mation or advice. We expressly disclaim any warranty of any kind, including any warranty of fitness for any customerʼs particular purpose,
with respect to such information or advice. As a matter of practical consideration, we also cannot assume any responsibility for updating or
correcting any such information or advice once it has been given, nor does the provision of information or advice create, expand or alter any
warranty with respect to the sale of our products.

Lincoln Electric is a responsive manufacturer, but the selection and use of specific products sold by Lincoln Electric is solely within the control
of, and remains the sole responsibility of the customer. Many variables beyond the control of Lincoln Electric affect the results obtained in
applying these types of fabrication methods and service requirements.

Subject to Change – This information is accurate to the best of our knowledge at the time of printing. Please refer to www.lincolnelectric.com
for any updated information.

CUSTOMER ASSISTANCE POLICY

Please Examine Carton and Equipment For Damage Immediately

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

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

Product _________________________________________________________________________________

Model Number ___________________________________________________________________________

Code Number or Date Code_________________________________________________________________

Serial Number____________________________________________________________________________

Date Purchased___________________________________________________________________________

Where Purchased_________________________________________________________________________

Whenever you request replacement parts or information on this equipment, always supply the information you
have recorded above. The code number is especially important when identifying the correct replacement parts.

On-Line Product Registration

- Register your machine with Lincoln Electric either via fax or over the Internet.

• For faxing: Complete the form on the back of the warranty statement included in the literature packet
accompanying this machine and fax the form per the instructions printed on it.

• For On-Line Registration: Go to our

Your Product”. Please complete the form and submit your registration.

Read this Operators Manual completely before attempting to use this equipment. Save this manual and keep it
handy for quick reference. Pay particular attention to the safety instructions we have provided for your protection.
The level of seriousness to be applied to each is explained below:

WEB SITE at www.lincolnelectric.com. Choose “Support” and then “Register

WARNING

This statement appears where the information must be followed exactly to avoid serious personal injury or loss of life.

CAUTION

This statement appears where the information must be followed to avoid minor personal injury or damage to this equipment.

TABLE OF CONTENTS

Page

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

Technical Specifications ........................................................................................A-1

Safety Precautions ..........................................................................................A-2

Correct Operational use ..................................................................................A-2

Stacking and Lifting.........................................................................................A-2

Input Power Connections ................................................................................A-2

Output Connections ........................................................................................A-3

Installation of Field Installed Options.....................................................................A-3

K843 Amptrol Installation Instructions ...................................................................A-4

Installation of Equipment Requied for Recommended Processes..........A-5 Thru A-6

––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Operational ......................................................................................................Section B

Safety Precautions.................................................................................................B-1

Meaning of Graphic Symbols...................................................................B-1 thru B-3

General Machine Description ................................................................................B-4

Recommended Processes & Equipment...............................................................B-4

Operational Features and Control .........................................................................B-4

Power Source Operation and Controls ....................................................B-5 thru B-7

Auxiliary Power Connections ..........................................................................B-8

Solid State Output Control ..............................................................................B-8

Case Features.................................................................................................B-8

Stick Welding ..................................................................................................B-9

Paralleling .......................................................................................................B-9

Machine & Circuit Protection...........................................................................B-9

––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

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

General, TIG, Stick, Wire Feeder Options.............................................................C-1

––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

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

Safety Precautions ................................................................................................D-1

Routine Maintenance.............................................................................................D-1

––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

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

Safety Precautions.................................................................................................E-1

How to Use Troubleshooting Guide.......................................................................E-1

Troubleshooting Guide.............................................................................E-2 thru E-5

Procedure for Replacing P.C. Boards............................................................E-6, E-7

––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

Wiring Diagrams..............................................................................................Section F

________________________________________________________________________

Parts Pages.................................................................................................P-234, P-688

vivi

A-1

INSTALLATION

TECHNICAL SPECIFICATIONS – DC-400

INPUT-THREE PHASE ONLY

Standard

Voltage

Frequency

100% Duty Cycle

Input Current at Rated Output (CVI)

60% Duty Cycle

50% Duty Cycle

A-1

500Amps/40V

84/42/34Amps

500Amps/40V

86/82/50/48/46/43Amps

230/460/575V/60Hz

220/230/380/400/415/440V/50/60Hz

400Amps/36V

78/39/31Amps

400Amps/36V

81/77/47/45/43/41Amps

450Amps/38V

83/41/33Amps

450Amps/38V

85/81/49/47/45/42Amps

RATED OUTPUT

Duty Cycle

100% 400 36

60% 450 38
50% 500 40

(1)

Amps Volts at Rated Amps

OUTPUT

OUTPUT MAXIMUM OPEN CIRCUIT VOLTAGE AUXILIARY POWER

Min.----60A 12V CV(22V CC) 57V. (CC) 45.5V. (CVI) 60Hz 115 VAC, 15 AMPS
Max.---500A 42V (CC, CV) 54V. (CC) 45.5V. (CVI) 50/60 Hz 42 VAC, 10 AMPS

RECOMMENDED INPUT WIRE AND FUSE SIZES FOR MAXIMUM RATED OUTPUT.

IN ADDITION, FOLLOW LATEST NATIONAL ELECTRICAL CODE AND LOCAL CODE.

INPUT

VOLTAGE /

FREQUENCY

230/60Hz
460/60Hz
575/60Hz

INPUT AMPERE

RATING ON

NAMEPLATE

@100%

Duty Cycle

78
39
31

TYPE 75°C

COPPER WIRE IN

CONDUIT AWG

(IEC) SIZES (mm

40°C(104°F)

3(25)
8(10)
10(6)

2

)

TYPE 75°C

GROUND WIRE IN

CONDUIT AWG

(IEC) SIZES (mm

6(16)
10(6)
10(6)

BUSSMANN SUPER-LAG

FUSE SIZE AND

2

)

FUSE SIZE CATALOG NUMBER

CATALOG NUMBER

100 REN-100

50 RES-50
40 RES-40

*

220/50/60Hz
230/50/60Hz
380/50/60Hz
400/50/60Hz
415/50/60Hz
440/50/60Hz

81
77
47
45
43
41

3(25)
3(25)
6(16)
6(16)
8(10)
8(10)

8(10)
8(10)
10(6)
10(6)
10(6)
10(6)

100 REN-100
100 REN-100

60 RES-60
60 RES-60
60 RES-60
50 RES-50

PHYSICAL DIMENSIONS

HEIGHT WIDTH DEPTH WEIGHT

27.50 in. 22.25 in. 32.0 in. 473 lbs.
699 mm 565 mm 988 mm 215 kg.

TEMPERATURE RANGES

OPERATING TEMPERATURE RANGE

-22°F to 104°F(-30°C +40°C)

(1) Based upon 10 minute time period (i.e., for 60% duty cycle, it is 6 minutes on an 4 minutes off).

STORAGE TEMPERATURE RANGE

-40°F to 140°F(-40°C+60°C)

* Use only Bussmann Super-Lag fuses specified. Other fuses may not protect the welder and may cause overheating and possible

fire damage.

Insulation class 155(F)

IDEALARC®DC-400

A-2

INSTALLATION

SAFETY PRECAUTIONS

WARNING

ELECTRIC SHOCK can kill.

• Do not touch electrically live parts or
electrode with skin or wet clothing.

• Insulate yourself from work and
ground.

• Always wear dry insulating gloves.

------------------------------------------------------------------------

FUMES AND GASES can be danger­ous.

• Keep your head out of fumes.

• Use ventilation or exhaust to remove
fumes from breathing zone.

------------------------------------------------------------------------

WELDING SPARKS can cause fire or
explosion.

• Keep flammable material away.

• Do not weld on closed containers.

------------------------------------------------------------------------

ARC RAYS can burn eyes and skin.

• Wear eye, ear and body
protection.

------------------------------------------------------------

See additional warning information at

front of this operatorʼs manual.

-----------------------------------------------------------

CORRECT OPERATIONAL USE

The machine should be located in a clean dry place
where there is free circulation of clean air such that air
movement in through the front and out through the
back will not be restricted. Dirt and dust that can be
drawn into the machine should be kept to a minimum.

A-2

Failure to observe these precautions can result in
excessive operating temperatures and nuisance shut­down of the machine.

LIMIT ON STACKING

WARNING

FALLING EQUIPMENT can cause

injury.

• Do not lift this machine using lift
bale if it is equipped with a heavy
accessory such as trailer or gas
cylinder.

• Lift only with equipment of adequate lifting
capacity.

• Be sure machine is stable when lifting.

• Do not stack more than three high.

• Do not stack the DC-400 on top of any other
machine.

The units may be stacked three high by observing the
following safety precautions:
A. Make sure the first or bottom unit is setting on a

level, well supported surface.

B. The units must be stacked with their fronts flush,

making sure the two holes in the base rails of the
unit being stacked on top are over the two pins
located on the top front corners of the unit it is
being stacked on.

Input Power Connections

By removing the rear access panel the three phase
input power is connected to the three line terminals on
the input contactor, and the earth grounding lead to
the grounding terminal on the input box floor marked
with the symbol. Install and reconnect panel for
the proper input voltage per the diagram pasted inside
the access panel cover.

See Technical Specification Page:

IDEALARC®DC-400

A-3

INSTALLATION

CAUTION

* Failure to follow these instructions

can cause immediate failure of com­ponents within the machine.

• When powering welder from a gener­ator be sure to turn off the welder
first, before generator is shut down in
order to prevent damage to welder.

Output Cable Connections

The output leads are connected to the output termi­nals marked “+” and “-”.
right and lower left corners of the front panel.

Output Cables

CABLE SIZES FOR COMBINED LENGTH OF

ELECTRODE AND WORK CABLE

CABLE LENGTHS

UP TO 50 ft

(15m)

They are located at the lower

MACHINE LOAD

400A

(100% DUTY

CYCLE)

3/0

85 mm

2

500A

(50% DUTY

CYCLE)

2/0

67 mm

2

REMOTE CONTROL ADAPTER CABLE (K864)

STRAIGHT PLUG (14 PIN)

TO POWER SOURCE

CABLE RECEPTACLE (6 SOCKET)

TO: 1) K857 REMOTE CONTROL

2) K963 HAND AMPTROL

3) K870 FOOT AMPTROL

CABLE RECEPTACLE (14 SOCKET)

TO LN-7 WIRE FEEDER

A “V” cable 12” (.30m) long to connect a K857
Remote Control (6 pin connector) with a wire-feeder
(14-pin connector) and the machine (14-pin connec­tor). If a remote control is used alone the wire-feeder
connection is then not used.

WARNING

ELECTRIC SHOCK can kill.

• Turn the power switch of the
welding power source “OFF”
before installing plugs on
cables or when connecting or
disconnecting plugs to weld­ing power source.

A-3

50 to 100 ft

(15-30 m)

100-150 ft

(30-46 m)

150-200 ft

(46-61 m)

200-250 ft

(67-76 m)

3/0

85 mm

3/0

85 mm

3/0

85 mm

4/0

107 mm

2/0

2

67 mm

2

3/0

2

85 mm

2

3/0

2

85 mm

2

4/0

2

107 mm

2

INSTALLATION OF FIELD INSTALLED
OPTIONS

Remote Output Control (K857 or K857-1
with K864 Adapter)

An optional “remote out control” is available. The
K857 or K857-1 are the same remote control options
that are used on other Lincoln power sources. The
K857 or K857-1 consist of a control box with 25 feet
(7.6 meters) or 100 feet (30.3 meters).

AMPTROL ADAPTER CABLE (843)

A five wire cable, 12” (.30m ) long, used for easy
connection of standard K963 Hand Amptrol or K870
Foot amptrol. The cable has a 6-pin MS-style
connector which connects to the Amptrol and termi­nals which connect to 75, 76, and 77 on the machine
terminal strip and to the case grounding screw. the
Amptrol will control the same range of output as the
current control on the welder. (if a smaller range of
control is desired for finer adjustment, a K775 Remote
may be used in conjunction with the Amptrol Adapter
Cable Kit.) The Amptrol arc start switch is nonfunc­tional unless used with a K799 Hi-Frequency Kit.

See Amptrol Adapter installation Instructions on next
page.

The K857 and K857-1 have a 6-pin connector and
K857 require a K864 adapter cable which connects to
the 14-pin connector on the case front.

IDEALARC®DC-400

A-4

INSTALLATION

A-4

Insulate

and tape.

K963-3 or

K870 Amptrol™

Limit Control

K775 Remote

connection.

Bolt and nut

AMPTROL™ PLUS

The power source "machine/remote" switch must be in "remote"

for Amptrol™ to control current. Accessories may be combined

and connected in two different ways, as shown below.

REMOTE LIMIT CONTROL

The Amptrol™ provides remote

current control from the minimum of

the power source to a maximum set

POWER

SOURCE

by the remote limit control.

K963-3 or K870 Amptrol™

K843

Adapter

Power source

terminal

AMPTROL™ ONLY

K843

K843 AMPTROL™ ADAPTER INSTALLATION INSTRUCTIONS

WARNING: TURN THE POWER SOURCE OFF BEFORE INSTALLATION

The Amptrol™ provides remote

current control through the full range

of the power source.

POWER

SOURCE

Adapter

77

76

75

strip

77

76

75 76 77

Black and white

leads not used.

Tape and

insulate.

Black and white leads

not used. Tape

and insulate.

FIG. 2

FIG. 1

This K843 adapter is used to connect AMPTROL™ (K963* or

K870), remote control (K775) accessories to DC-400 with

remote control power sources.

IDEALARC®DC-400

A-5

INSTALLATION

A-5

INSTALLATION OF EQUIPMENT
REQUIRED FOR RECOMMENDED
PROCESSES

WIRE FEEDER CONTROL CABLE CONNECTIONS

For control cable with 14-pin connector:

Connect control cable to 14-pin connector on the front
panel of the machine. See the appropriate connection
diagram for the exact instructions for the wire feeder
being used. Refer to Operation Section B (Auxiliary
Power and Control Connections) for connector pin
functions.

For control cable with terminal strip connectors:

The control cable from the wire feeding equipment is
connected to the terminal strips behind the control
panel*. A strain relief box connector is provided for
access into the terminal strip section. A chassis
ground screw is also provided below the terminal strip
marked with the symbol for connecting the auto­matic equipment grounding wire. See the appropriate
connection diagram for the exact instructions for the
wire feeder being used.

A cover (Lincoln Electric Part Number S17062-3) is
available for the unused 14-pin connector to protect it
against dirt and moisture.

* See Terminal Strip Connections section for access

to the terminal strips.

CONNECTION OF DC-400 TO LN-22 OR LN-25

MULTIPROCESS SWITCH CONNECTION AND
OPERATION

PURPOSE

A Multiprocess Switch has been designed for use with
the DC-400. With this switch installed on the DC-400,
it permits easy changing of the polarity of the wire
feed unit connected and also provides separate termi­nals for connection of stick or air carbon arc. The
Multiprocess Switch is available as either a factory
installed or field installed option.

NOTE: IF THE DC-400 IS TO BE USED FOR BOTH

SEMIAUTOMATIC/AUTOMATIC AND
AIR CARBON ARC, THEN A MULTI­PROCESS SWITCH IS REQUIRED.

DESIGN

The Multiprocess Switch consists of a 3-position
switch assembly that is mounted in a sheet metal
enclosure that has two output terminals on each end
of the box. The two terminals on the left side of the
box are for connection of wire feed electrode and work
leads. The two terminals on the right side of the box
are for connection of work and electrode for stick or
air carbon arc. The output terminals are protected
against accidental contact by hinged covers.

The switch mounts to the front of the DC-400 by
means of a bracket that fastens to the case sides.
Two 4/0 (107 mm2) leads connect the switch assem­bly to each output stud.

STICK/

a) Turn off all power.

b) Place output terminals switch into the “ON” posi-

tion.

c) Connect the electrode cable to the output terminal

of polarity required by electrode. Connect the work
lead to the other terminal.

d) Place the OUTPUT CONTROL Switch at “LOCAL”

position unless a Remote Control is connected to
the DC-400.

e) Place MODE SWITCH in “CONSTANT VOLTAGE

(FCAW, GMAW)”.

NOTE: The output terminals are energized at all

times.

IDEALARC®DC-400

CONNECTIONS

1. Connect wire feed unit electrode and work cables
through the rectangular strain relief holes in the
base of the DC-400 to the output studs on the left
side of the box.

2. Connect wire feeder control cable and make other
terminal strip connections as specified on the con­nection diagram for the Lincoln wire feeder being
used. “Electrode” and “Work” are connected to the
left side of the Multiprocess Switch.

3. Connect stick or air carbon arc electrode and work
cables through the rectangular strain relief holes in
the base of the DC-400 to the output studs on the
right side of the box.

A-6

INSTALLATION

A-6

OPERATION

The operation of the switch is as follows:

A semiautomatic or automatic wire feed unit electrode
and work cables are connected to the terminals on the
left side of the box. Stick or air carbon arc electrode
and work leads are connected to the terminals on the
right side of the box. There are three positions on the
switch. With the switch in the left position, the wire
feed terminals are electrode negative. In the center
position, the wire feeder terminals are electrode posi­tive. In both the left and center switch position, the
right side stick terminals are disconnected. In the
right switch position, the wire feed terminals are dis­connected from the DC-400 and the stick terminals
connected. The polarity of the stick terminals is
marked on the end of the box. To change polarity, the
electrode and work leads must be interchanged. In
the stick position, the stick terminals are energized at
all times.

CONNECTIONS

To stick
electrode
holder or
air carbon
arc torch

User supplied
4/0 (107 mm )
jumper

2

To semi-

auto or

auto

equipment

WORK

ELECTRODE

+

MULTIPROCESS SWITCH

To change stick polarity, reverse the leads at the (+)
and (-) terminals on the right side of the Multiprocess
Switch.

NOTE: When a DC-400 equipped with Multiprocess

Switch is mounted on an undercarriage, the
undercarriage handle in the resting position
can hit the case of the Multiprocess Switch.
This does no harm, but if the user desires, a
1/4” or 3/8” bolt and nut may be placed in the
hole in the undercarriage tow bar to limit the
travel of the undercarriage handle.

(For those applications where it is not
have separate work cables for stick and semiautomat­ic welding.)

If both stick and semiautomatic welding is done on the
same workpiece, only one work lead is required. To
do this, connect a 4/0 (107 mm2) jumper from the
work terminal on the semiautomatic side to the termi­nal to be used for work on the stick side. The work
lead from the semiautomatic side then serves as the
work lead for both semiautomatic and stick welding.

necessary to

STICK, TIG OR AIR/CARBON ARC *

a) Turn off all power.

b) Disconnect all wire feed unit control, electrode, and

work leads.

c) Place MODE SWITCH in the “CONSTANT CUR-

RENT (STICK/TIG)” for air carbon arc.

d) For stick, TIG or air carbon arc, place OUTPUT

TERMINALS switch into the “ON” position. With
the DC-400 connected for stick, TIG or air carbon
arc welding, the output terminals will be energized
at all times.

*NOTE: If stick welding, TIG welding or air carbon arc

cutting is to be done on the DC-400 along
with semi-automatic/automatic welding, then
a K804-1 Multiprocess Switch is required. If
the Multiprocess Switch is not used, then all
control, electrode, and work leads to wire
feed equipment must
the DC-400 before connecting the DC-400 for
stick or air carbon arc cutting.

be disconnected from

IDEALARC®DC-400

B-1

OPERATION

B-1

SAFETY PRECAUTIONS

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.

• This next section applies to DC-400ʼs without
the Capacitor Discharge Option:

When using a DC-400 power source with wire feeders
which do not have an electrical trigger interlock (or
with wire feeders with the electrical trigger interlock in
the OFF position), there will be a small spark if the
electrode contacts the work or ground within several
seconds after releasing the trigger.

When used with some wire feeders with the electrical
trigger interlock in the ON position, the arc can restart
if the electrode touches the work or ground during
these several seconds.

OUTPUT CONTROL DIAL

Output (Control)

Increase/Decrease of
Output (Voltage or
Current)

OUTPUT CONTROL “LOCAL-REMOTE” SWITCH

Remote Output Voltage
or Current Control

Local Output Voltage or
Current Control

WARNING

• Be sure to select OUTPUT TERMINALS “REMOTE
ON/OFF” for operation with wire feeders that have
leads numbered 2 and 4.

MEANINGS OF GRAPHIC SYMBOLS

The DC-400 nameplate has been redesigned to use
international symbols in describing the function of the
various components. Below are the symbols used.

POWER ON-OFF SWITCH

Input (Power)

On

CIRCUIT BREAKER

Circuit Breaker

THERMAL PROTECTION LIGHT

High Temperature

ARC CONTROL SWITCH

Gas Metal Arc
Welding

Increase/Decrease
of Inductance

Off

Low Inductance

High Inductance

IDEALARC®DC-400

B-2

OPERATION

B-2

OUTPUT TERMINALS SWITCH

ARC FORCE CONTROL DIAL

Output (Voltage)

On

Remote On/Off

Shielded Metal Arc
Welding

Gas Tungsten Arc
Welding

RATING PLATE

Three Phase Power

Transformer

Rectifier

Rectified DC Output

Constant Voltage
Characteristic

MODE SWITCH

Arc Force Current

Increase/Decrease
of Current

VOLTMETER SWITCH

Voltmeter

Positive Electrode

Negative Electrode

EARTH GROUND CONNECTION

Signifying the Earth
(Ground) Connection

Do not switch if
output voltage
or current is
present.

Constant
Voltage
(Submerged Arc
Welding)

Constant
Voltage (Flux
cored arc
weldin,gas
metal arc weld­ing).

Constant
Current (shield
metal arc weld­ing, gas tung­sten arc weld­ing).

IDEALARC®DC-400

B-3

RATING PLATE (Continued)

OPERATION

B-3

NEMA EW 1

IEC 60974-1

Designates welder complies with National Electrical Manufacturers
Association requirements EW 1. (Export Model only)

Designates welder complies with International Electrotechnical
Commission requirements 60974-1. (European model only)

Three Phase Power

Transformer

Rectifier

Rectified DC Output

Constant Voltage Characteristic

S

Constant Current Characteristic

Line Connection

Shielded Metal Arc Welding

Flux Cored Arc Welding

Submerged Arc Welding

Designates Welder can be used in environments with
increased hazard of electric shock.

(IEC model only)

IP21
CE

Degree of protection provided by the enclosure

Designates welder complies with low voltage directive and with
EMC directive. (Export Model only)

IDEALARC®DC-400

B-4

OPERATION

GENERAL MACHINE DESCRIPTION

B-4

OUTPUT TERMINALS “ON” OR OUTPUT TERMI­NALS “REMOTE”

The DC-400 is an SCR controlled three phase DC
power source. It is designed with a single range
potentiometer control.

RECOMMENDED PROCESSES
& EQUIPMENT

The DC-400 model is designed for all open arc
processes including Innershield®and GMAW all solid
wire and gas procedures within the capacity of the
machine, plus the capability of stick and TIG welding
and air carbon arc gouging up to 5/16” (8mm) diame­ter. A mode switch selects CV (FCAW, GMAW), CV
Submerged Arc, or CC (Stick/TIG). Stick welding per­formance is similar to that of the R3R-500.

The DC-400 is designed to be used with the LN-7, LN­7 GMA, LN-8, LN-9, LN-9 GMA, LN-10, DH-10, LN­23P, LN-25, LF-72, LF-74 or LN-742 semiautomatic
wire feeders, the NA-3, NA-5 and NA-5R automatics,
and the LT-56 and LT-7 tractors, within the 400
ampere capacity of the machine. The DC-400 Diode
Kit option is required to utilize the cold start and cold
electrode sensing features of the NA-3, NA-5 and NA­5R.

OPERATIONAL FEATURES &
CONTROLS

ARC CHARACTERISTICS

Through the unique combination of the transformer,
three phase semiconverter rectifier, capacitor bank,
arc control choke, and the solid state control system,
outstanding arc characteristics are achieved on con­stant voltage.

In addition, an arc force control enables the DC-400 to
stick weld as well as the R3R-500.

This switch provides an alternative to the “2 to 4”
jumpering function by energizing the machineʼs output
regardless of whether “2 or 4” is jumpered or not.

POLARITY SELECTION

Polarity selection is made by appropriately connecting
the electrode and work welding cables to either the

“+“ stud or to the “-” stud. Select “VOLTMETER”
switch for “+” or “-” electrode, for the remote (#21)

work sensing lead.

VOLTMETER SWITCH “+” ELECTRODE OR “-”
ELECTRODE

This switch selects electrode polarity for the remote
(#21) work sensing lead of automatic or semiautomat­ic equipment.

115 VOLT POWER SWITCH

The power input contactor operates from an auxiliary
115 volt transformer that is energized through the
POWER toggle switch on the machine control panel.
“ I “ is on and “0” is off.

PILOT LIGHT

A white light on the machine control panel indicates
when the power source input contactor is closed. This
means the main power transformer and all auxiliary
and control transformers are energized.

THERMAL PROTECTION LIGHT

An amber light on the machine control panel indicates
when either of the two protective thermostats have
opened. Output power will be removed but input
power will still be applied to the machine.

INPUT CONTACTOR

OUTPUT CONTROL

The OUTPUT control, a small 2 watt potentiometer, is
calibrated from 1 to 10. The OUTPUT control serves
as a voltage control in the CV position and a current
control in the CC position.

MACHINE OUTPUT CONTROL SWITCH “LOCAL”
OR “REMOTE”

The machine output can be controlled by either the
OUTPUT control on the machine control panel, the
output control on the wire feed unit, or an optional
“remote control” that is available. This switch selects
the mode of control, either “LOCAL” or “REMOTE”.

IDEALARC®DC-400

The power source is equipped with an input contactor.

B-5

OPERATION

B-5

POWER SOURCE OPERATION AND
CONTROLS

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.

Duty Cycle and Time Period

The DC-400 is rated at the following duty cycles:

DUTY CYCLE * AMPS VOLTS

100%

60%
50%

* Based upon 10 minute time period (i.e., for 60% duty

cycle, it is 6 minutes on and 4 minutes off).

Overloading the DC-400 may result in opening of an
internal protective thermostat as indicated by the
amber thermal protection light turning on.

STARTING THE MACHINE

The POWER toggle switch at the extreme right side of
the control panel in the “I“ position energizes and clos­es the three phase input contactor from a 115 volt
auxiliary transformer. This in turn energizes the main
power transformer.

The machine is de-energized when the POWER
switch is in the “0” position.

The white light below the POWER switch indicates
when the input contactor is energized.

OUTPUT CONTROL DIAL

The OUTPUT control to the right of the center of the
control panel is a continuous control of the machine
output. The control may be rotated from minimum to
maximum while under load to adjust the machine out­put.

The machine is equipped with line voltage compensa­tion as a standard feature. This will hold the output
constant except at maximum output of the machine,
through a fluctuation of ±10% input line voltage.

400
450
500

36
38
40

OUTPUT CONTROL “LOCAL-REMOTE” SWITCH

The OUTPUT CONTROL toggle switch on the control
panel labeled “LOCAL-REMOTE” gives the operator
the option of controlling the output at the machine
control panel or at a remote station. For remote con­trol, the toggle switch is set in the “REMOTE” position
and controlled at the wire feed unit control, or by con­necting a K775 control to terminals 75, 76, and 77 on
the terminal strip at the front of the machine, or by
connecting a K857 control to the 14-pin connector on
the front of the machine. For control at the machine
control panel, the toggle switch is set in the “LOCAL”.

(Exception: When used with an LN-9, LN-9 GMA or
NA-5 wire feeder, the OUTPUT CONTROL switch
must be in the “REMOTE” position or automatic shut­down of the LN-9 or NA-5 may occur.)

POLARITY SELECTION

Polarity selection is made by appropriately connecting
the electrode and work welding cables to either the

+” stud or to the “-” stud. Select “VOLTMETER”

“
switch for “+” or “-” electrode for the remote (#21)

work sensing lead.

VOLTMETER SWITCH

Select “+” for positive electrode or “-” for negative
electrode polarity for the remote (#21) work sensing
lead of automatic or semiautomatic equipment.

THERMAL PROTECTION LIGHT

The amber thermal protection light will be lit if either of
the two protective thermostats have opened. The out­put power will be disabled but input power will still be
applied to the welder. (Refer to Machine and Circuit
Protection section).

MODE SWITCH

The large MODE SWITCH on the left side of the
machine, labeled “Constant Voltage (Submerged Arc),
Constant Voltage (FCAW/GMAW) and Constant
Current (Stick/TIG)”, is used to select the proper
welder characteristics for the process being used.

The CV (FCAW/GMAW) Mode permits the DC-400 to
produce essentially a flat output characteristic that can
be varied from approx. 12 to 42 volts.

©

IDEALARC®DC-400

B-6

OPERATION

In this position, the dynamic characteristics of the
machine under welding conditions provide optimum
welding characteristics for Innershield®welding, other
open arc processes including short arc MIG welding,
and air carbon arc. Most submerged arc welding can
also be done in this mode.

The CV (Submerged Arc) Mode also produces an
essentially flat output characteristic that can be varied
from approximately 12 to 42 volts. The dynamic
characteristics of the CV Submerged Arc Mode make
possible improved submerged arc welding over that
possible using the Constant Voltage Innershield
Mode. The improvement is most noticeable on high
deposition, slow travel speed welds.

B-6

OUTPUT TERMINALS SWITCH

The OUTPUT TERMINALS toggle switch on the con­trol panel labeled “REMOTE - ON” allows the welder
output to be activated remotely or to be always on.
For remote operation, the toggle switch is set in
“REMOTE” position and the welder output will be acti­vated when 2 and 4 are closed when using a wire­feeder. For welder output to always be activated, set
the switch to the “ON” position.

110-115V AC and 40-42V AC Auxiliary
Power and Control Connections

14-PIN CONNECTOR

There are no means provided to switch between any
of the modes remotely. Do not change the position of
the MODE SWITCH if output voltage or current is pre­sent as this may damage the switch.

The CC Mode permits the DC-400 to produce a con­stant current output characteristic through the range of
60-500 amps with an open circuit voltage of approxi­mately 57 volts (54V on 50/60 Hz). Stick welding and
TIG are done with this position of the Mode Switch.

ARC FORCE CONTROL DIAL (Effective only in CC
mode)

The ARC FORCE control is calibrated from one to ten.
For most welding, the dial should be set at approxi­mately midrange, 5-6. Adjustments up or down can
then be made depending on the electrode, proce­dures, and operator preference. Lower settings will
provide less short circuit current and a softer arc. A
setting that is too low may cause the electrode to stick
in the puddle. Higher settings will provide a higher
short circuit current and a more forceful arc.
Excessive spatter may result if the control setting is
too high. For most TIG welding applications adjust
this control to a minimum for best operating character­istics.

ARC CONTROL SWITCH (Effective only in CV
FCAW/GMAW mode)

The 14-pin connector receptacle supplies auxiliary
power.

40-42V AC is available at receptacle pins I and K. A
10 amp circuit breaker protects this circuit.

On the Domestic and Export models 110-115V AC is
available at receptacle pins A and J. A 10 amp circuit
breaker protects this circuit. Note that the 40-42V AC
and 110-115V AC circuits are electrically isolated from
each other.

FRONT VIEW OF 14-PIN

CONNECTOR RECEPTACLE

K=42

A=32

B=GND

L=SPARE

C=2

D=4

E=77

M =SPARE

J=31

I=41

N=SPARE

H=21

G=75

F=76

The ARC CONTROL is a tapped switch numbered
from 1 to 5 and changes the pinch effect of the arc.
This control is most useful in processes that utilize a
“shorting” metal transfer and controls the spatter, fluid­ity, and bead shape. The pinch effect is increased by
turning the control clockwise.

For all applications, a good starting point for the ARC
CONTROL is a midrange dial setting of 3. The control
can be increased or decreased as desired.

IDEALARC®DC-400

PIN LEAD NO.

A
B
C
D
E
F
G
H

I

J

K

L
M
N

32

GND

2

4
77
76
75
21
41
31
42

---

---

---

FUNCTION

110 - 115V AC (Domestic & Export)
CHASSIS CONNECTION
TRIGGER CIRCUIT
TRIGGER CIRCUIT
OUTPUT CONTROL
OUTPUT CONTROL
OUTPUT CONTROL
WORK CONNECTION
40-42V AC
110-115V AC (Domestic & Export)
40-42V AC

---

---

---

B-7

OPERATION

Terminal Strip Connections

Terminal strip TS2 located behind the hinged control
panel on the front of the power source supplies
110-115V AC. A 10 amp circuit breaker protects this
circuit. Note that this 110-115V AC is also available in
the 14-pin connector on the Domestic and Export
models.

To gain access to the terminal strips simply remove
the six #10 sheet metal screws from the perimeter of
the welder nameplate as shown below. Tilt panel for­ward so it rests in a horizontal position. See Table
showing Front View of 14-Pin Connector Receptacle
for lead number functions.

1

6

2

B-7

5

4

3

230V AC Auxiliary Power for Water Cooler
(European and Export models)

A Continental European receptacle is located on the
rear panel for supplying 230V AC to a water cooler. A

3.5 amps circuit breaker which is also located on the
rear panel protects this circuit from excessive over­loads or short circuits.

Machine and Circuit Protection

The power source is thermostatically protected with
proximity thermostats against overload or insufficient
cooling. One thermostat is located on the nose of the
center bottom primary coil and a second thermostat is
attached to the lead connection the secondaries.
Both thermostats are connected in series with 2-4 cir­cuit. If the machine is overloaded, the primary ther­mostat will open, the output will be zero, and the
amber thermal protection light will be on.

The fan will continue to run. The secondary thermo­stat will open either with an excessive overload or
insufficient cooling. The output will be zero and the
amber protection light will be off.

IDEALARC®DC-400

B-8

AUXILIARY POWER CONNECTIONS

The power source is equipped to furnish nominally
110-115 volt AC and 40-42 volt AC auxiliary power for
operating wire feeding equipment, etc. The auxiliary
power is available at the 14-pin MS-style connector
receptacle on the control panel and/or at a terminal
strip behind the hinged control panel on the front of
the power source. 110-115V AC is available at recep­tacle pins A and J (Domestic and Export models only),
and terminals 31 and 32 (all models). 40-42V AC is
available only at receptacle pins I and K. The 110­115V AC and the 40-42V AC are isolated circuits and
each is protected by a 10 amp circuit breaker.

OPERATION

B-8

The SCR snubber board consists of a capacitor and
resistor connected across each SCR and across the
entire bridge and MOVʼs to protect the control circuitry
and SCRʼs from transient voltages. The snubber
board is mounted on the back of the case front.

The SCR firing circuit, the control fault protection cir­cuit, the power-up delay circuit, and the power circuit
are mounted on the control PC board located behind
the front control panel. (The front control panel hinges
down for easy access to the board.)
The starting circuit board is located on the back of the
control box.

REMOTE CONTROL CONNECTIONS

Remote control connections are available both at a
14-pin connector receptacle located on the control
panel, and on terminal strips with screw connections
located behind the hinged control panel on the front of
the power source.

OUTPUT CONNECTIONS

The output terminals are recessed on the case front
and labeled “+” and “-”.

INPUT CONNECTIONS

The three input lines are brought in through the rear
panel of the power source and attached to the input
contactor. Removal of the removable access panel
makes the contactor accessible for the input cable
connections.

INPUT LINE VOLTAGE COMPENSATION

The power source is equipped with input line voltage
compensation as standard. For a line voltage fluctua­tion of ±10% the output will remain essentially con­stant. This is accomplished through the feedback net­work in the control circuit.

SOLID STATE OUTPUT CONTROL

The output of the welder is electronically controlled by
SCRʼs instead of mechanical contactors, providing
extra long life for highly repetitive welding applica­tions.

SOLID STATE CONTROL SYSTEM

The control circuitry consists of six basic circuits: (1)
the SCR snubber network, (2) the SCR firing circuit,
(3) the control/fault protection circuit, (4) the starting
circuit, (5) the power-up delay circuit, and (6) the
power circuit.

IDEALARC®DC-400

MACHINE COOLING

The fan pulls air in through the louvered front of the
machine over the internal parts and exhausts out the
louvered rear of the machine. The fan motor is fully
enclosed, has sealed ball bearings, requires no lubri­cation, and operates when the power switch is turned
on.

CASE FEATURES

The machine uses a 32” (813mm) long base. The low
profile case facilitates installation of the machine
under a workbench and stacking the machines three
high to conserve floor space.

The case front incorporates a recessed control panel
where all the machine controls are mounted. This
recessed panel protects the controls and minimizes
the possibilities of accidental contact. This control
panel can be easily opened to permit access to the
enclosed control section which contains the terminal
strips, PC board, etc.

The output lead terminals are also recessed to avoid
any object or person accidentally coming in contact
with an output terminal. Strain relief is provided by
holes in the front of the base. The leads are routed up
through these holes to the output terminals. This pre­vents any damage of the output studs or insulation of
same in the event the cables are pulled excessively.
An output stud cover protects against accidental con­tact with the output studs. Cover hinges upward for
access to the studs.

The individual case sides are removable for easy
access for internal service or inspection. These are
removable even though the machines are stacked
three high.

B-9

The case rear, top section, is equipped with a remov­able access panel. This provides easy access to the
input contactor, easy connection and reconnection of
input leads, and easy access for service or inspection.

The total construction of the machine permits outdoor
operation. The enclosure is designed with air intake
louvers that keep dripping water from being drawn into
the unit. The transformer, SCR bridge assembly, and
choke are double-dipped in a special corrosion resis­tant coating.

A permanent lifting hook is located at the top of the
machine and is positioned so that it acts as nearly as
possible through the center of gravity. This lift hook is
so positioned that it fits without interference under the
base of the second machine when stacking.

ARC FORCE SELECTOR
(Effective only on CC for Stick and TIG Processes)

An ARC FORCE selector is provided similar to that
used on the R3R. This control allows the user to
select the ideal arc force for the procedure and elec­trode being used.

ARC CONTROL
(Effective Only When Using CVI Mode)

OPERATION

B-9

DIODE OPTION

The DC-400 Diode option is required to utilize the cold
start and cold electrode sensing features of the NA-3,
NA-5 or NA-5R. When this option is not used with an
NA-3, NA-5 or NA-5R, see the DC-400/NA-3, DC­400/NA-5 or DC-400/NA-5R connection diagram for
instructions on how to disable this circuit. If the circuit
is not disabled, the wire cannot be inched down.

Machine & Circuit Protection
(Thermal Protection Light)

The power source is thermostatically protected with
proximity thermostats against overload or insufficient
cooling. One thermostat is located on the nose of the
center bottom primary coil and a second thermostat is
attached to the lead connecting the secondaries.
Both thermostats are connected in a series with the 2­4 circuit. If the machine is overloaded, the primary
thermostat will be open, the output will be zero, and
the amber thermal protection light will be on. The fan
will continue to run. The secondary thermostat will
open either with an excessive overload or insufficient
cooling. The output will be zero and the amber pro­tection light will be on. When the thermostats reset
the protection light will be off.

The ARC CONTROL is a five-position switch that
changes the pinch effect of the arc. This results in the
control of spatter, fluidity, and bead shape. The ARC
CONTROL is set to provide optimum welding depend­ing on the process being used, position, electrode,
etc. The pinch effect is increased by turning the con­trol clockwise and may be adjusted while the machine
is in operation.

MODE SWITCH

A MODE SWITCH selects between Constant Voltage
(FCAW/GMAW), Constant Voltage (Submerged Arc),
and Constant Current (Stick/TIG).

STICK WELDING

When the DC-400 is used for stick welding or air car­bon arc, the control leads and welding cables to any
semiautomatic or automatic wire feeders must be dis­connected from the DC-400 for maximum safety
(unless the Multiprocess switch option is installed).

PARALLELING

The power source is also protected against overloads
on the SCR bridge assembly through an electronic
protection circuit. This circuit senses an overload on
the power source and limits the output to 550 amps by
phasing back the SCRʼs.

Protection is provided to protect the circuitry from
accidental grounds. If the customer accidentally
“grounds” 75, 76, or 77 to the positive output lead, the
DC-400 will be reduced to a low value, thus prevent­ing any damage to the machine. If the ground occurs
between 75, 76, 77 and the negative output lead, one
of the PC board “self-restoring” fuses will blow, pre­venting any machine damage.

There are no provisions on the DC-400 to permit par­alleling.

IDEALARC®DC-400

C-1

ACCESSORIES

C-1

GENERAL

K2149-1 - Work Lead Package

K804-1 - Multi-Process Switch

K841 - Undercarriage

K843 - Amptrol Adaptor Kit

TIG OPTIONS

K1798 - Terminal Strip Adapter Cable

K586-1 - Deluxe Adjustable Gas Regulator and Hose

Kit

K775 - Remote Limit Switch

K828-1 - Capacitor Discharge Circuit

K864 - Remote Control A

WIRE FEEDER

K2327-4 - LF-72 Wire Feeder, Base Model (No Gun)

K2327-5 - LF-72 Wire Feeder, Bench Model,

Standard Duty

K2327-6 - LF-72 Wire Feeder, Bench Model, Heavy

Duty

K2327-7 - LF-72 Wire Feeder, Bench Model, Heavy

Duty (No Gun)

K870 - Foot Amptrol™

K930 - 2 - TIG Module

K936 - 1 Control Cable - 9 to 14

K937 - 45 - TIG Module Control Cable Extension

K939 - 1 Docking Kit

K963 - 3 - Hand Amptrol™

STICK

K857 - Remote Output Control - 25 ft. (7.6 m)

K857-1 - Remote Output Control - 100 ft. (30.5 m)

K864 - Remote Control Adapter

K704 - Accessory Kit - 400 Amp

IDEALARC®DC-400

D-1

MAINTENANCE

SAFETY PRECAUTIONS

WARNING

-----------------------------------------------------------------------

ELECTRIC SHOCK can kill.

Have an electrician install and ser-

•

vice this equipment.

• Turn the input power off at the fuse

box before working on equipment.

• Do not touch electrically live parts or electrode

with skin or wet clothing.

• Insulate yourself from work and ground

• Always wear dry insulating gloves.

------------------------------------------------------------------------

See additional warning information

throughout this operatorʼs manual and
the Engine manual as well.

-----------------------------------------------------------

ROUTINE MAINTENANCE

D-1

1. The fan motor has 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 machine at regular intervals.

3. In extremely dusty locations, dirt may accumulate

on the remote control terminal strip TS1. Wipe or
blow this terminal strip off at regular intervals. This
is particularly important in damp locations.

IDEALARC®DC-400

E-1

TROUBLESHOOTING

HOW TO USE TROUBLESHOOTING GUIDE

WARNING

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.

__________________________________________________________________________

E-1

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 (SYMP­TOMS)”. 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.

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.

---------------------------------------------------------------------

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.

CAUTION

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.

IDEALARC®DC-400

E-2

Observe all Safety Guidelines detailed throughout this manual

PROBLEMS

(SYMPTOMS)

TROUBLESHOOTING

POSSIBLE

CAUSE

E-2

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.

1. Faulty input contactor (CR1).

2. Low line voltage.

1. Supply line fuse blown.

2. Contactor power circuit dead.

3. Broken power lead.

4. Wrong input voltage.

5. Open input contactor coil.

6. POWER “I/0” switch (S1) not
closing.

1. Trigger circuit between #2 and #4
leads is not being closed.

1. Repair or Replace.

2. Check input power.

1. Replace if blown - look for reason
first.

2. Check control transformer T2 and
associated leads.

3. Check input voltage at contactor.

4. Check voltage against instruc­tions.

5. Replace coil.

6. Replace switch.

1. Make sure trigger circuit is being
closed.

Machine has minimum output and no
control.

2. Electrode or work lead loose or
broken.

3. Open main transformer (T1) pri­mary or secondary circuit.

4. Defective Control PC Board.

5. Primary or secondary thermostats
open.

1. Terminals 75, 76 or 77 grounded
to positive

output.

2. Repair Connection.

3. Repair.

4. Replace. See Procedure for
Replacing PC Boards.

5. Amber thermal protection light is
on: Check for overheating; make
sure fan is operating and there is
no obstruction to free air flow.

1. Check 75, 76, or 77 for ground to
positive output circuit. Nearly
zero ohms to ground indicates a
grounded circuit. A value greater
than a few thousand ohms is nor­mal. Self-restraining fuses on PC
Board automatically reset within a
few seconds after ground is
cleared.

CAUTION

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.

IDEALARC®DC-400

E-3

Observe all Safety Guidelines detailed throughout this manual

PROBLEMS

(SYMPTOMS)

TROUBLESHOOTING

POSSIBLE

CAUSE

E-3

RECOMMENDED

COURSE OF ACTION

Machine has high output or pulsing
output and no control.

Machine has low output and no
control.

1. Terminals 75, 76, or 77 grounded
to negative

1. OUTPUT CONTROL “LOCAL­REMOTE” switch (S2) in wrong
position.

2. OUTPUT CONTROL switch
faulty.

3. Open in feedback circuitry.

4. Faulty Control PC Board.

5. OUTPUT control potentiometer
circuit open (lead 75).

output.

1. Check 75, 76, or 77 for ground to
negative output circuit. Nearly
zero ohms to ground indicates a
grounded circuit. A value greater
than a few thousand ohms is nor­mal. Self-restoring fuses on PC
Board automatically reset within a
few seconds after ground is
cleared.

1. Check position of switch.

2. Check switch & replace if faulty.

3. Check wiring and control PC
Board wiring harness plugs.

4. Replace. See Procedure for
Replacing PC Boards.

5. Check and replace potentiometer
if faulty. Check wiring of lead
#75.

Machine does not have maximum
output.

Machine will not shut off.

1. One input fuse blows.

2. One phase of main transformer
open.

3. Faulty Control PC Board.

4. OUTPUT control potentiometer.

5. OUTPUT control potentiometer
leads 210, 211 or 75 open.

1. Input contactor contacts frozen.

2. Defective POWER “1/0” switch,
(S1).

1. Check and replace if blown after
checking for reason for blown
fuse.

2. Check for open and repair.

3. Replace. See Procedure for
Replacing PC Boards.

4. Check and Replace if faulty.

5. Check and repair broken leads.

1. Check and replace if necessary.

2. Replace.

CAUTION

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.

IDEALARC®DC-400

E-4

Observe all Safety Guidelines detailed throughout this manual

PROBLEMS

(SYMPTOMS)

TROUBLESHOOTING

POSSIBLE

CAUSE

E-4

RECOMMENDED

COURSE OF ACTION

Variable or sluggish welding arc.

OUTPUT control not functioning on
the machine.

1. Poor work or electrode connec­tion.

2. Welding leads too small.

3. Welding current or voltage too
low.

4. Defective main SCR bridge.

5. Microswitch S4C or S4D actuator
defective.

1. OUTPUT CONTROL switch in
wrong position.

2. Faulty OUTPUT control switch.

3. Faulty OUTPUT control poten­tiometer.

4. Leads or connections open in
control circuit.

1. Check and clean all connections.

2. Check table in instruction manual.

3. Check procedures for recom­mended settings.

4. Check and replace if defective.

5. Check and replace if defective.
(If S4C or S4D actuator is found
defective, replace mode switch
cam also.)

1. Place switch in “LOCAL”.

2. Check and replace if found faulty.

3. Check and replace if found faulty.

4. Check lead continuity and con­nections for an open and repair if
necessary.

OUTPUT control not functioning on
“REMOTE” control.

5. Faulty Control PC Board.

1. OUTPUT CONTROL switch in
wrong position.

2. Faulty OUTPUT CONTROL
switch.

3. Faulty remote control potentiome­ter.

4. Leads or connections open in
control circuit.

5. Faulty Control PC Board.

5. Replace. See Procedure for
Replacing PC Boards.

1. Place switch in “REMOTE”.

2. Check and replace if found faulty.

3. Check and replace if found faulty.

4. Check all leads and connections,
internal or remote, for continuity.
Repair if necessary.

5. Replace. See Procedure for
Replacing PC Boards.

CAUTION

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.

IDEALARC®DC-400

E-5

Observe all Safety Guidelines detailed throughout this manual

PROBLEMS

(SYMPTOMS)

TROUBLESHOOTING

POSSIBLE

CAUSE

E-5

RECOMMENDED

COURSE OF ACTION

Poor arc striking with semiautomatic
or automatic wire feeders.

Poor arc characteristics.

1. Defective start circuit.

2. Poor work connection.

3. Improper procedures.

4. Defective Control PC Board.

1. Start circuit energized at all times
(read switch CR3 not closing).

2. Defective Start PC Board.

3. Defective Control PC Board.

4. Capacitor(s) in output circuit
failed. A failure is indicated if the
small vent plug on top of a capac­itor is raised or blown out.

1. Check Start PC Board and reed
switch CR3.

2. Work connection must be ade­quate for application.

3. Adjust procedures for improved
starting.

4. Replace. See Procedure for
Replacing PC Boards.

1. Short reed switch CR3 leads
together. If welding improves,
replace reed switch.

2. If problem is still present with
reed switch shorted, unplug Start
PC Board. If problem disap­pears, replace Start PC Board.

3. Replace. See Procedure for
Replacing PC Boards.

4. Replace entire bank of capaci­tors. Do not
capacitors.

WARNING:
The liquid electrolyte in these
capacitors is toxic. Avoid contact
with any portion of your body.
Clean up vented electrolyte using
rubber gloves and a water
damped cloth. Any electrolyte
which gets on skin, clean with
soap and water.

replace individual

ARC CONTROL has no effect in CV
(FCAW/GMAW) mode with short cir­cuit transfer processes.

115VAC Receptacle not working.

1. Defective R1, L1, S4C, S4D actu­ator or S5.

1. Circuit Breaker Tripped.

2. Defective Circuit Breaker.

3. Broken connection in wiring.

1. Check and replace if found defec­tive. (If S4C or S4D actuator is
found defective, replace mode
switch cam also.)

1. Reset circuit breaker. Make sure

load on does not exceed 15A rat­ing of circuit breaker.

2. Replace

3. Check all wiring going to recepta-

cle and circuit breaker for possible
broken connection.

CAUTION

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.

IDEALARC®DC-400

E-6

PROCEDURE FOR REPLACING PC BOARDS

TROUBLESHOOTING

E-6

FAULT PROTECTION OPERATION

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.

----------------------------------------------------------------------

When a PC Board is suspected to be defective, the follow­ing procedure must be followed:

1. Visually inspect the PC Board. If the board has fuses,
check to see if any are blown. Are any of the compo­nents damaged? Is a conductor on the back side of the
board damaged? If electrical damage is visible on the
PC Board, inspect the machine wiring for grounds or
shorts to avoid damaging a new PC Board, Install a new
PC Board only after a visual inspection of the PC Board
and machine wiring is satisfactory.

2. If the problem is remedied by a new PC Board, install the
old PC Board and see if the problem still exists. If the
problem does not return with the old board:
a) Check the PC Board harness plug and PC Board plug

for contamination, corrosion or oversize.

b) Check leads in the harness for loose connections.

CONNECTING THE REMOTE CONTROL TO THE
MACHINE

Extreme caution must be observed when installing or
extending the wiring of a remote control. Improper connec­tion of this unit can lead to failure of the output control rheo­stat or the control circuit. Only the green lead can and
should be grounded to the machine case. When extending
the standard remote control, make sure the leads are the
same and the splice is waterproof. Be very careful not to
ground the cable when in use and donʼt let the lugs touch
against the case.

OUTPUT VOLTAGE

The output circuit voltage of the machine should be
adjustable from 10 to 46 volts in CV. In the CC mode, the
open circuit voltage should be approximately 57 volts (54
volts on 50/60 Hz) except at near minimum settings of the
output control where it may be lower. If any other condition
exists, refer to the Troubleshooting Guide.

The overload protection circuit, in the Control PC Board will
limit the welding current (heat) to 550 amps if a short or
overload is applied to the machine. (Refer to the Machine
and Circuit Protection section).

CHECKING SNUBBER CIRCUIT

In case of an SCR malfunction or failure the snubber
assembly should be checked. Turn the machine off and
remove the sides of the machine. (See the instruction man­ual parts list for the exact location.)

1. Visually inspect the snubber assembly for overheated
components or damaged components.

CHECKING OUTPUT CONTROL RHEOSTAT ON
MACHINE

Turn machine off (“0” position).

Remove the control panel screws and open the control
panel (see the section on Terminal Strip Connections for
screw locations).

Turn the OUTPUT CONTROL switch to “REMOTE”.

Disconnect the harness plug from the Control PC Board.

With an ohmmeter on X1K, connect it to lead 210 and 75 on
R4.

Exercise caution to avoid damaging POT taps.

POWER “I/0” SWITCH CHECK

1. Turn off the machine power input (“0” position). S1 has
115V across it when the input power is connected.

2. Isolate the switch to be tested by removing all connecting
leads.

3. Check to make sure the switch is making connections
with an ohmmeter. The meter should read zero resis­tance.

4. Put the ohmmeter on X1K scale and measure the resis­tance between the terminal and the case of the machine
(touch a self-tapping screw). Reading should be infinite.

5. If either step (3) or step (4) fails, replace the switch.

CAUTION

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.

IDEALARC®DC-400

E-7

REMOTE CONTROL CHECK

TROUBLESHOOTING

2. Power Diode Test

E-7

Disconnect the remote output control and connect an
ohmmeter across 75 to 76 and rotate the rheostat in
the remote control. The resistance reading should go
from zero to 10K ohms. Repeat with ohmmeter
across 75 and 76 with same results. Connect ohm­meter across 75 and 77. The reading should be 10K
ohms. A lower reading will indicate a shorted or par­tially shorted rheostat. A very high reading will indi­cate an open rheostat. In either of the last two cases,
replace rheostat. Check cable for any physical dam­age.

POWER RECTIFIER BRIDGE ASSEMBLY
CHECKING PROCEDURE

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.

----------------------------------------------------------------------

1. Bridge and Device Isolation (See the instruc­tion manual parts list for the exact location.)

Disconnect the following leads from the bridge,
shown in Diagram 1:

a) Establish the polarity of the ohmmeter leads

and set to X10 scale.

b) Connect the ohmmeter positive lead to anode

and negative lead to cathode.

c) Reverse the leads of the ohmmeter from

Step b.

d) A shorted diode will indicate zero or an equally

low resistance in both directions. An open
diode will have an infinite or high resistance in
both directions and a good diode will have a
low resistance in Step b and Step a much high­er resistance in Step c.

3. Power Silicon Controlled Rectifier Test

a) Connect the ohmmeter (set to m X10 scale)

leads to the anode and cathode.

b) Reverse the leads of the ohmmeter from Step

a.

c) A shorted SCR will indicate zero or an equally

low resistance in one or both directions.

d) Establish the polarity of the ohmmeter.

Connect the positive lead to the gate and the
negative lead to the cathode.

a) Unplug P3 (G1, G2, G3 and 204) from the

Control PC Board.

b) Unplug P5 from the Snubber PC Board.

c) Secondary leads X1, X2, and X3 from the

anodes of the SCRʼs and cathodes of the
diodes.

d) Disconnect positive bridge lead from shunt and

positive capacitor bank lead and from lug with
triple 204 leads.

e) Perform the following steps 2 and 3. If diodes

and SCRʼs are not shorted, bridge test is com­pleted. If any device appears shorted, discon­nect the cathode lead of each diode (4 total)
and repeat Steps 2 and 3.

e) An open gate circuit will have an infinite or high

resistance. A good gate circuit will read a low
resistance, but not zero ohms. If gate circuit
reads zero ohms, check gate harness for
shorts between gate leads and 204 before
replacing SCR.

CAUTION

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.

IDEALARC®DC-400

F-1

DIAGRAMS

F-1

IDEALARC®DC-400

F-2

WIRING DIAGRAM FOR CODE 11829

DIAGRAMS

F-2

IDEALARC®DC-400

NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The specific diagram for a particular code is pasted inside the

machine on one of the enclosure panels. If the diagram is illegible, write to the Service Department for a replacement. Give the equipment code number.

F-3

WIRING DIAGRAM FOR CODE 11831

DIAGRAMS

F-3

IDEALARC®DC-400

NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The specific diagram for a particular code is pasted inside the

machine on one of the enclosure panels. If the diagram is illegible, write to the Service Department for a replacement. Give the equipment code number.

F-4

WIRING DIAGRAM FOR CODES 11832, 11833 and 11834

DIAGRAMS

F-4

IDEALARC®DC-400

NOTE: This diagram is for reference only. It may not be accurate for all machines covered by this manual. The specific diagram for a particular code is pasted inside the

machine on one of the enclosure panels. If the diagram is illegible, write to the Service Department for a replacement. Give the equipment code number.

NOTES

IDEALARC®DC-400

NOTES

IDEALARC® DC-400

G Keep your head out of fumes.
G Use ventilation or exhaust to

remove fumes from breathing zone.

G Turn power off before servicing.

G Do not operate with panel open or

guards off.

WARNING

G Los humos fuera de la zona de res-

piración.

G Mantenga la cabeza fuera de los

humos. Utilice ventilación o
aspiración para gases.

G Gardez la tête à l’écart des fumées.
G Utilisez un ventilateur ou un aspira-

teur pour ôter les fumées des zones
de travail.

G Vermeiden Sie das Einatmen von

Schweibrauch!

G Sorgen Sie für gute Be- und

Entlüftung des Arbeitsplatzes!

G Mantenha seu rosto da fumaça.
G Use ventilação e exhaustão para

remover fumo da zona respiratória.

G Desconectar el cable de ali-

mentación de poder de la máquina
antes de iniciar cualquier servicio.

G Débranchez le courant avant l’entre-

tien.

G Strom vor Wartungsarbeiten

abschalten! (Netzstrom völlig öff­nen; Maschine anhalten!)

G Não opere com as tampas removidas.
G Desligue a corrente antes de fazer

serviço.

G Não toque as partes elétricas nuas.

G No operar con panel abierto o

guardas quitadas.

G N’opérez pas avec les panneaux

ouverts ou avec les dispositifs de
protection enlevés.

G Anlage nie ohne Schutzgehäuse

oder Innenschutzverkleidung in
Betrieb setzen!

G Mantenha-se afastado das partes

moventes.

G Não opere com os paineis abertos

ou guardas removidas.

Spanish

AVISO DE

PRECAUCION

French

ATTENTION

German

WARNUNG

Portuguese

ATENÇÃO

Japanese

Chinese

Korean

Arabic

LEIA E COMPREENDA AS INSTRUÇÕES DO FABRICANTE PARA ESTE EQUIPAMENTO E AS PARTES DE USO, E SIGA AS
PRÁTICAS DE SEGURANÇA DO EMPREGADOR.

WARNING

Spanish

AVISO DE

PRECAUCION

G Do not touch electrically live parts or

electrode with skin or wet clothing.

G Insulate yourself from work and

ground.

G No toque las partes o los electrodos

bajo carga con la piel o ropa moja­da.

G Aislese del trabajo y de la tierra.

G Keep flammable materials away.

G Mantenga el material combustible

fuera del área de trabajo.

G Wear eye, ear and body protection.

G Protéjase los ojos, los oídos y el

cuerpo.

French

ATTENTION

German

WARNUNG

Portuguese

ATENÇÃO

Japanese

Chinese

Korean

Arabic

G Ne laissez ni la peau ni des vête-

ments mouillés entrer en contact
avec des pièces sous tension.

G Isolez-vous du travail et de la terre.

G Berühren Sie keine stromführenden

Teile oder Elektroden mit Ihrem
Körper oder feuchter Kleidung!

G Isolieren Sie sich von den

Elektroden und dem Erdboden!

G Não toque partes elétricas e elec-

trodos com a pele ou roupa molha­da.

G Isole-se da peça e terra.

G Gardez à l’écart de tout matériel

inflammable.

G Entfernen Sie brennbarres Material!

G Mantenha inflamáveis bem guarda-

dos.

G Protégez vos yeux, vos oreilles et

votre corps.

G Tragen Sie Augen-, Ohren- und Kör-

perschutz!

G Use proteção para a vista, ouvido e

corpo.

READ AND UNDERSTAND THE MANUFACTURER’S INSTRUCTION FOR THIS EQUIPMENT AND THE CONSUMABLES TO BE
USED AND FOLLOW YOUR EMPLOYER’S SAFETY PRACTICES.

SE RECOMIENDA LEER Y ENTENDER LAS INSTRUCCIONES DEL FABRICANTE PARA EL USO DE ESTE EQUIPO Y LOS
CONSUMIBLES QUE VA A UTILIZAR, SIGA LAS MEDIDAS DE SEGURIDAD DE SU SUPERVISOR.

LISEZ ET COMPRENEZ LES INSTRUCTIONS DU FABRICANT EN CE QUI REGARDE CET EQUIPMENT ET LES PRODUITS A
ETRE EMPLOYES ET SUIVEZ LES PROCEDURES DE SECURITE DE VOTRE EMPLOYEUR.

LESEN SIE UND BEFOLGEN SIE DIE BETRIEBSANLEITUNG DER ANLAGE UND DEN ELEKTRODENEINSATZ DES HER­STELLERS. DIE UNFALLVERHÜTUNGSVORSCHRIFTEN DES ARBEITGEBERS SIND EBENFALLS ZU BEACHTEN.

• World's Leader in Welding and Cutting Products •

• Sales and Service through Subsidiaries and Distributors Worldwide •

Cleveland, Ohio 44117-1199 U.S.A. TEL: [phone] FAX: [phone] WEB SITE: www.lincolnelectric.com