Lincoln Electric R3R-500, R3R-300 User Manual

SVM139-A

June 1998

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.

SERVICE MANUAL

World’s Leader in Welding and Cutting Products Premier Manufacturer of Industrial Motors

Sales and Service through subsidiaries and Distributors Worldwide

22801 St. Clair Ave. Cleveland, Ohio 44117-1199 U.S.A. Tel. [phone]

For use with machine code numbers 9534, 9537, 9874 and 9884

IDEALARC

®

R3R-300, -400 and -500

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SAFETY

i i

IDEALARC R3R

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 weld-

ing 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.

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.

WARNING

ELECTRIC AND
MAGNETIC FIELDS
may be dangerous

2.a. Electric current flowing through any conductor causes
localized Electric and Magnetic Fields (EMF). Welding
current creates EMF fields around welding cables and
welding machines

2.b. EMF fields may interfere with some pacemakers, and
welders having a pacemaker should consult their physician
before welding.

2.c. Exposure to EMF fields in welding may have other health
effects which are now not known.

2.d. All welders should use the following procedures in order to
minimize exposure to EMF fields from the welding circuit:

2.d.1.

Route the electrode and work cables together - Secure
them with tape when possible.

2.d.2. Never coil the electrode lead around your body.

2.d.3. Do not place your body between the electrode and

work cables. If the electrode cable is on your right
side, the work cable should also be on your right side.

2.d.4. Connect the work cable to the workpiece as close as

possible to the area being welded.

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

1.h. To avoid scalding, do not remove the
radiator pressure cap when the engine is
hot.

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 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 Diesel Engines

The Above For Gasoline Engines

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SAFETY

ii ii

IDEALARC R3R

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.

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.

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 below Threshold Limit Values (TLV)
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.

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.c. 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.d. 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.e. Also see item 1.b.

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SAFETY

iii iii

IDEALARC R3R

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.

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.

WELDING 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.

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SAFETY

iv iv

IDEALARC R3R

PRÉCAUTIONS DE SÛRETÉ

Pour votre propre protection lire et observer toutes les instructions
et les précautions de sûreté specifiques qui parraissent dans ce
manuel aussi bien que les précautions de sûreté générales suiv­antes:

Sûreté Pour Soudage A L’Arc

1. Protegez-vous contre la secousse électrique:

a. Les circuits à l’électrode et à la piéce sont sous tension

quand la machine à souder est en marche. Eviter tou­jours tout contact entre les parties sous tension et la
peau nue ou les vétements mouillés. Porter des gants
secs et sans trous pour isoler les mains.

b. Faire trés attention de bien s’isoler de la masse quand

on soude dans des endroits humides, ou sur un planch­er metallique ou des grilles metalliques, principalement
dans les positions assis ou couché pour lesquelles une
grande partie du corps peut être en contact avec la
masse.

c. Maintenir le porte-électrode, la pince de masse, le câble

de soudage et la machine à souder en bon et sûr état
defonctionnement.

d. Ne jamais plonger le porte-électrode dans l’eau pour le

refroidir.

e. Ne jamais toucher simultanément les parties sous ten-

sion 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.

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
enroule le câble-électrode autour de n’importe quelle partie
du corps.

3. Un coup d’arc peut être plus sévère qu’un coup de soliel,
donc:

a. Utiliser un bon masque avec un verre filtrant approprié

ainsi qu’un verre blanc afin de se protéger les yeux du
rayonnement de l’arc et des projections quand on soude
ou quand on regarde l’arc.

b. Porter des vêtements convenables afin de protéger la

peau de soudeur et des aides contre le rayonnementde
l’arc.

c. Protéger l’autre personnel travaillant à proximité au

soudage à l’aide d’écrans appropriés et non-inflamma­bles.

4. Des gouttes de laiter en fusion sont émises de l’arc de
soudage. Se protéger avec es vêtements de protection libres
de l’huile, tels que les gants en cuir, chemise épaisse, pan­talons sans revers, et chaussures montantes.

5. Toujours porter des lunettes de sécurité dans la zone de
soudage. Utiliser des lunettes avec écrans lateraux dans les
zones où l’on pique le laitier.

6. Eloigner les matériaux inflammables ou les recouvrir afin de
prévenir ttout risque d’incendie dû étincelles.

7. Quand on ne soude pas, poser la pince à une endroit isolé
de la masse. Un court-circuit accidental peut provoquer un
échauffement et un risque d’incendie.

8. S’assurer que la masse est connectée le plus prés possible
de la zone de travail qu’il est pratique de la faire. Si on place
la masse sur la charpente de la construction ou d’autres
endroits éloignés de la zone de travail, on augmente le
risque de voir passer le courant de soudage par les chaines
de levage, câbles de grue, ou atres circuits. Cela peut
provoquer des risques d’incendie ou d’echauffement des
chaines et des câbles jusqu’à ce qu’ils se rompent.

9. Assurer une ventilation suffisante dans la zone de soudage.
Ceci est particuliérement important pour le soudage de tôles
galvanisées plombées, ou cadmiées ou tout autre métal qui
produit des fumées toxiques.

10. Ne pas souder en présence de vapeurs de chlore provenant
d’opéerations de dégraissage, nettoyage ou pistolage. La
chaleur ou les rayons de l’arc peuvent réagir avec les
vapeurs du solvant pour produire du phosgéne (gas forte­ment roxique) ou autres produits irritants.

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 l’électricité 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, l’installation et l’entretien du poste
seront effectués par un électricien qualifié.

3. Avant de faires des travaux à l’interieur de poste, la
debrancher à l’interrupteur à la boite de fusibles.

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

MASTER TABLE OF CONTENTS FOR ALL SECTIONS

v v

IDEALARC R3R

Page

Safety.................................................................................................................................................i-iv

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

Technical Specifications .............................................................................................................A-2

Safety Precautions......................................................................................................................A-5

Select Suitable Location (Stacking, Tilting, Lifting) ....................................................................A-5

Input Connections.......................................................................................................................A-6

Reconnect Procedure .................................................................................................................A-8

Output Connections (Stick, TIG, Air/Carbon Arc Cutting)..........................................................A-9

Operation...............................................................................................................................Section B

Safety Instructions ......................................................................................................................B-2

General Description ....................................................................................................................B-3

Controls and Settings.................................................................................................................B-4

Welding Operation ......................................................................................................................B-6

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

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

Safety Precautions......................................................................................................................D-2

Routine and Periodic Maintenance ............................................................................................D-2

General Component Locations...................................................................................................D-3

Theory of Operation .............................................................................................................Section E

Troubleshooting and Repair.................................................................................................Section F

How To Use Troubleshooting Guide ...........................................................................................F-2

Troubleshooting Guide ................................................................................................................F-4

Test Procedures ........................................................................................................................F-10

Oscilloscope Waveforms ..........................................................................................................F-35

Replacement Procedures..........................................................................................................F-39

Retest After Repair....................................................................................................................F-61

Electrical Diagrams..............................................................................................................Section G

Parts Manual................................................................................................................................P-206

RETURN TO MAIN INDEX

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Section A-1 Section A-1

IDEALARC R3R

TABLE OF CONTENTS

- INSTALLATION SECTION -

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

Technical Specifications, Idealarc R3R-300 ...............................................................................A-2

Technical Specifications, Idealarc R3R-400 ...............................................................................A-3

Technical Specifications, Idealarc R3R-500 ...............................................................................A-4

Safety Precautions......................................................................................................................A-5

Select Suitable Location.............................................................................................................A-5

Lifting .................................................................................................................................A-5

Tilting .................................................................................................................................A-5

Stacking................................................................................................................................A-5

Input Connections.......................................................................................................................A-6

Ground Connection ..............................................................................................................A-6

Input Supply Connections....................................................................................................A-6

Input Wire and Fuse Size ...............................................................................................A-7

Reconnect Procedure .................................................................................................................A-8

Output Connections (Stick, TIG, Air/Carbon Arc).......................................................................A-9

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INSTALLATION

A-2 A-2

IDEALARC R3R

TECHNICAL SPECIFICATIONS - IDEALARC R3R-300

INPUT - THREE PHASE ONLY

Standard Voltage Input Current @ Rated Output

230V 56A
460V 28A

RATED OUTPUT

Duty Cycle Amps Volts at Rated Amps

100% 230 29

60% 300 32
35% 375 35

OUTPUT

Current Range Maximum Open Circuit Voltage

45 to 375 Amps 67 VDC

RECOMMENDED INPUT WIRE AND FUSE SIZES AT 60% DUTY CYCLE

Input Wire Size Ground Wire Size

Input Voltage / Fuse Input Ampere Type 75°C Type 75°C

Frequency (Super Lag) Rating on Copper Wire in Copper Ground

or Breaker Size Nameplate Conduit Wire in Conduit

Volts/Hz AWG (IEC) Sizes AWG (IEC) Sizes

230/60 80 56 8 (10 mm2) 8 (10 mm2)
460/60 40 28 10 (6 mm2) 10 (6 mm2)

PHYSICAL DIMENSIONS

Height Width Depth Weight

27.50 in. 22.25 in. 33.10 in. 350 lbs.

(700 mm) (565 mm) (840 mm) (159 kg)

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INSTALLATION

A-3 A-3

IDEALARC R3R

TECHNICAL SPECIFICATIONS - IDEALARC R3R-400

INPUT - THREE PHASE ONLY

Standard Voltage Input Current @ Rated Output

230V 74A
460V 37A

RATED OUTPUT

Duty Cycle Amps Volts at Rated Amps

100% 300 32

60% 400 36
35% 500 40

OUTPUT

Current Range Maximum Open Circuit Voltage

60 to 500 Amps 67 VDC

RECOMMENDED INPUT WIRE AND FUSE SIZES AT 60% DUTY CYCLE

Input Wire Size Ground Wire Size

Input Voltage / Fuse Input Ampere Type 75°C Type 75°C

Frequency (Super Lag) Rating on Copper Wire in Copper Ground

or Breaker Size Nameplate Conduit Wire in Conduit

Volts/Hz AWG (IEC) Sizes AWG (IEC) Sizes

230/60 125 74 6 (16 mm2) 6 (16 mm2)
460/60 60 37 10 (6 mm2) 10 (6 mm2)

PHYSICAL DIMENSIONS

Height Width Depth Weight

27.50 in. 22.25 in. 33.10 in. 402 lbs.

(700 mm) (565 mm) (840 mm) (182 kg)

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INSTALLATION

A-4 A-4

IDEALARC R3R

TECHNICAL SPECIFICATIONS - IDEALARC R3R-500

INPUT - THREE PHASE ONLY

Standard Voltage Input Current @ Rated Output

230V 88A
460V 44A

RATED OUTPUT

Duty Cycle Amps Volts at Rated Amps

100% 600 44

60% 500 40
35% 375 35

OUTPUT

Current Range Maximum Open Circuit Voltage

75 to 625 Amps 67 VDC

RECOMMENDED INPUT WIRE AND FUSE SIZES AT 60% DUTY CYCLE

Input Wire Size Ground Wire Size

Input Voltage / Fuse Input Ampere Type 75°C Type 75°C

Frequency (Super Lag) Rating on Copper Wire in Copper Ground

or Breaker Size Nameplate Conduit Wire in Conduit

Volts/Hz AWG (IEC) Sizes AWG (IEC) Sizes

230/60 150 88 4 (25 mm2) 6 (16 mm2)
460/60 70 44 8 (10 mm2) 8 (10 mm2)

PHYSICAL DIMENSIONS

Height Width Depth Weight

27.50 in. 22.25 in. 33.10 in. 446 lbs.

(700 mm) (565 mm) (840 mm) (202 kg)

Read this entire installation section before you
start installation.

SAFETY PRECAUTIONS

ELECTRIC SHOCK can kill.

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

• Insulate yourself from the work
and ground.

• Always wear dry insulating gloves.

Only qualified personnel should install, use, or ser­vice this equipment.

SELECT SUITABLE LOCATION

Place the Idealarc R3R in a dry location where clean
cooling air can flow freely in through the front louvers
and out through the rear louvers. Keep dust, dirt, and
other foreign materials that can be drawn into the
machine to a minimum. Failure to observe these pre­cautions can lead to excessive operating temperatures
and nuisance shut-downs.

LIFTING

FALLING EQUIPMENT can cause
injury.

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

• Lift only with equipment of adequate lifting capacity.

• Be sure the machine is stable when lifting.

• Do not stack more than three high.

• Do not stack the R3R on top of any other machine.

A permanent lift bail is located at the top of the
machine, positioned at the center of gravity for stable
lifting. R3R weights are as follows:

R3R-300 350 pounds (159 kilograms)
R3R-400 402 pounds (182 kilograms)
R3R-500 446 pounds (202 kilograms)

TILTING

Place the machine on a secure, level surface. Any sur­faces you place it on other than the ground must be
firm, non-skid, and structurally sound.

STACKING

Idealarc R3Rs may be stacked three high. The bottom
machine must be on a stable, hard, level surface capa­ble of supporting the weight of up to three machines
(1350 pounds/1608 kilograms). Be sure that the two
pins in the roof of the bottom machine fit into the holes
in the base of the machine above. The lift bail is posi­tioned so that it fits without interference under the
base of the second machine.

Do not stack heavier machines on top of lighter
machines. For example, do not place an R3R-500 on
top of an R3R-400 or an R3R-400 on top of an
R3R-300.

INSTALLATION

A-5 A-5

IDEALARC R3R

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WARNING

WARNING

INPUT CONNECTIONS

ELECTRIC SHOCK can kill.

• Have a qualified electrician
install and service this equip­ment.

• Turn the input power off at the
fuse box before working on this
equipment.

• Do not touch electrically hot
parts.

• Insulate yourself from the work and ground.

• Always wear dry insulating gloves.

Be sure the voltage, phase, and frequency of the input
power is as specified on the rating plate, located on
the case front control panel. See Figure A.1. Also see
appropriate Technical Specifications page for input
and ground wire requirements.

Input supply line ground lead entry is through a hole
located at the top of the case rear panel. A removable
door covers the input connection box, which contains
the input contactor (CR1) and reconnect panel assem­bly for multiple voltage machines.

GROUND CONNECTION

The welder frame must be grounded. A stud marked
with the symbol located on the floor of the input
box is provided for this purpose. See the U.S.
National Electrical Code for details on proper ground­ing methods.

INPUT SUPPLY CONNECTIONS

Input power is connected to the three line terminals on
the input contactor. See Figure A.2. Be sure the volt­age, phase, and frequency of the input power is as
specified on the rating plate.

INSTALLATION

A-6 A-6

IDEALARC R3R

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FIGURE A.1 – RATING PLATE LOCATION

1

WARNING

1. RATING PLATE

Have a qualified electrician connect the input power
leads to the L1, L2, and L3 terminals of the input con­tactor. Follow all national and local electrical codes.
Use a three-phase line. Refer to the connection dia­gram located on the inside of the access panel cover
for proper input voltage connection. Also see Figure

A.3.

INPUT WIRE AND FUSE SIZE

Fuse the input circuit with super lag fuses or delay
type circuit breakers as recommended on the
Technical Specifications page. Choose an input and
grounding wire size according to local or national
codes; also see the appropriate Technical
Specifications page. Using fuses or circuit breakers
smaller than recommended may result in “nuisance”
shut-offs from welder inrush currents, even if you are
not welding at high currents.

INSTALLATION

A-7 A-7

IDEALARC R3R

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FIGURE A.2 – INPUT POWER SUPPLY CONNECTIONS

1. INPUT SUPPLY LINE

2. INPUT CONTACTOR CR1

3. RECONNECT PANEL

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INSTALLATION

A-8 A-8

IDEALARC R3R

FIGURE A.3 - INPUT CONNECTION DIAGRAM FOR 208, 208/230 and 230/460 VOLTS AC, 50/60 HZ

THE LINCOLN ELECTRIC CO., CLEVELAND OHIO U.S.A.

1. TURN OFF THE INPUT POWER USING THE DISCONNECT SWITCH AT THE FUSE BOX.

CONNECTION FOR LOWEST RATING PLATE VOLTAGE, 50 OR 60 HZ.

CONNECTION FOR HIGHEST RATING PLATE VOLTAGE, 50 OR 60 HZ.

CODES.

4. CONNECT TERMINAL MARKED TO GROUND PER LOCAL AND NATIONAL ELECTRIC

LEAST 600 VOLT INSULATION.

2. DISCONNECT AND INSULATE THE H2 LEAD TERMINAL WITH TAPE TO PROVIDE AT

5. MOUNT THE LINKS IN THE POSITIONS SHOWN WITH THE PROVIDED HEX NUTS.

USE. SECURE THE REMAINING HEX NUTS IN PLACE.

DOUBLE UP THE LINKS IN TWO OF THE POSITIONS TO SAVE THEM FOR FUTURE

5. MOUNT THE LINKS IN THE POSITIONS SHOWN WITH THE PROVIDED HEX NUTS.

M15009

3-17-95E

LINK

1. TURN OFF THE INPUT POWER USING THE DISCONNECT SWITCH AT THE FUSE BOX.

CODES.

4. CONNECT TERMINAL MARKED TO GROUND PER LOCAL AND NATIONAL ELECTRIC

LEAST 600 VOLT INSULATION.

2. DISCONNECT AND INSULATE THE H3 LEAD TERMINAL WITH TAPE TO PROVIDE AT

3. CONNECT L1, L2 & L3 INPUT SUPPLY LINES AND H2 TRANSFORMER LEADS
TO THE INPUT SIDE OF THE CR1 CONTACTOR AS SHOWN.

3. CONNECT L1, L2 & L3 INPUT SUPPLY LINES AND H3 TRANSFORMER LEADS
TO THE INPUT SIDE OF THE CR1 CONTACTOR AS SHOWN.

INPUT SUPPLY CONNECTION DIAGRAM

Do not touch electrically live parts

Only qualified persons should install,
use or service this equipment

removed

servicing

Do not operate with covers

Disconnect input power before

NOTE: MACHINES ARE SHIPPED FROM FACTORY CONNECTED FOR OVER 300 VOLTS

DUAL VOLTAGE MACHINE

GND

H2

INPUT

LINES

L1

H1

L2

L3

{

CR1

V

U

W

CONTACTOR

H3

PILOT

TRANSF.

LINK

GND

H3

INPUT

LINES

L1

H1

L2

L3

{

CR1

V

U

W

CONTACTOR

H2

PILOT

TRANSF.

IMPORTANT: CHANGE LINK POSITIONS AND PILOT TRANSFORMER CONNECTIONS.

RECONNECT PROCEDURE

Multiple input voltage welders are shipped connected
for the highest voltage listed on the machine’s rating
plate. Before installing the welder, be sure the recon­nect panel is connected for the proper voltage.

Failure to follow these instructions can cause immedi­ate failure of components in the welder.

To reconnect a multiple voltage machine to a different
voltage, remove input power. Follow the input con­nection diagram, located on the inside access panel
cover, appropriate for your machine’s input voltage.
These same connection diagrams are shown below.

For 208, 208/230 & 230/460 volts AC - see Figure A.3.

CAUTION

The output (welding) cables are connected to the out­put terminals marked “+” and “-”. See Table A.1 for
recommended cable sizes for the combined lengths of
electrode and work cables. The output terminals are
located at the lower right and lower left corners of the
front panel. Strain relief for the cables is provided by
routing them through the rectangular holes in the base
before connecting them to the output terminals. See
Figure A.4.

NOTE: If the welder comes equipped with the polarity

switch option, the output terminals are labeled
“electrode” and “to work.”

The output terminals are energized at all times.

INSTALLATION

A-9 A-9

IDEALARC R3R

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FIGURE A.4 - OUTPUT TERMINAL CONNECTIONS

1

2

3

1. NEGATIVE (-) WELDING CABLE CONNECTION

2. POSITIVE (+) WELDING CABLE CONNECTION

3. CABLE STRAIN RELIEF HOLES

OUTPUT CONNECTIONS (STICK, TIG, AIR/CARBON ARC CUTTING)

WARNING

TABLE A.1 - CABLE SIZES FOR COMBINED LENGTHS OF COPPER ELECTRODE

AND WORK CABLES

Up to 100 ft 100 - 150 ft 150 - 200 ft 200 - 250 ft

Machine Size (30 m) (30 - 46 m) (46 - 61 m) (67 - 76 m)
300 Amp 1/0 1/0 2/0 3/0

(60% Duty 54 mm

2

54 mm

2

68 mm

2

86 mm

2

Cycle)
400 Amp 2/0 2/0 3/0 4/0

(60% Duty 68 mm

2

68 mm

2

86 mm

2

108 mm

2

Cycle)
500 Amp 2/0 3/0 3/0 4/0

(60% Duty 68 mm

2

86 mm

2

86 mm

2

108 mm

2

Cycle)

NOTES

A-10 A-10

IDEALARC R3R

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Section B-1 Section B-1

IDEALARC R3R

TABLE OF CONTENTS

- OPERATION SECTION -

Operation...............................................................................................................................Section B

Safety Instructions ......................................................................................................................B-2

General Description ....................................................................................................................B-3

Recommended Processes ...................................................................................................B-3

Design Features and Advantages ........................................................................................B-3

Welding Capability................................................................................................................B-3

Controls and Settings ................................................................................................................B-4

Welding Operation ......................................................................................................................B-6

Operating Steps ...................................................................................................................B-6

Local Control..................................................................................................................B-6

Remote Control..............................................................................................................B-6

Pocket Amptrol ..............................................................................................................B-6

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B-2

B-2

IDEALARC R3R

OPERATING INSTRUCTIONS

Read and understand this entire section of operating
instructions before operating the machine.

SAFETY INSTRUCTIONS

ELECTRIC SHOCK can kill.

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

• Insulate yourself from the 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 containers that have held com­bustibles.

ARC RAYS can burn.

• Wear eye, ear, and body protection.

Observe additional Safety Guidelines detailed in
the beginning of this manual.

WARNING

OPERATION

GENERAL DESCRIPTION

The Idealarc R3R is an SCR controlled constant cur­rent DC output power source for welding and cutting.
The R3R-300 uses a single range potentiometer con­trol. The R3R-400 and R3R-500 have separate low
and high range controls. The welder’s unique combi­nation of 3 phase transformer, SCR/Diode bridge rec­tifier, arc control choke, and solid state control system
deliver outstanding arc characteristics. For stick weld­ing, an Arc Force Control enables the Idealarc-R3R to
create a soft welding arc for critical applications or a
forceful driving arc for heavy duty applications.

RECOMMENDED PROCESSES

The Idealarc R3R is recomended for stick and DC TIG
welding and air/carbon arc gouging.

DESIGN FEATURES AND ADVANTAGES

• Input line voltage compensation keeps output con­stant for fluctuations of ± 10%.

• Hinged front control panel provides easy access to
printed circuit boards and other control circuitry.

• Fully enclosed fan motor with permanently lubri­cated, sealed ball bearings needs no maintenance.

• Fully recessed control panel protects controls and
minimizes accidental contact.

• Recessed output terminals reduces chance of acci­dental contact.

• Low profile case permits installation under a work­bench.

• Removable rear access panel provides easy access
to input contactor and input lead connections.

• Removable case sides provide easy access for ser­vice or inspection, even when machines are stacked.

• Dripproof enclosure design permits outdoor operation.

• Double-dipped transformer, SCR bridge, and choke
resist corrosion.

WELDING CAPABILITY

The Idealarc R3R has the following duty cycle ratings.
If the duty cycle is exceeded, a thermal protector will
shut off the machine output until it cools to normal
operating temperature. The amber thermal protection
indicator light will turn on until the machine cools.

60% Duty Cycle* Amps Volts

R3R-300 300 32
R3R-400 400 36
R3R-500 500 40

*Based on a 10 minute time period. For example, a 60% duty cycle
means 6 minutes on and 4 minutes off.

OPERATION

B-3 B-3

IDEALARC R3R

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CONTROLS AND SETTINGS

All operator controls and settings are located on the
case front assembly. See Figure B.1 for their loca­tions.

FIGURE B.1 – CASE FRONT CONTROLS

1. POWER SOURCE PILOT LIGHT: This light indi-

cates that input power is applied to the R3R and
that the on/off switch is in the ON position.

2. ON/OFF POWER TOGGLE SWITCH: Energizes

or de-engergizes the input contactor which is pow­ered by the 115 volt auxiliary transformer. The
switch turns the machine ON or OFF. Position “I”
is ON; position “0” is OFF.

3. ARC FORCE SELECTOR: Allows you to select

the ideal arc force according to the procedure and
electrode being used for CC stick. It controls the
amount of current added to the welding current
when the electrode shorts to the work. At mini­mum setting, no extra short circuit current is
added. The arc will be softer and have less spat­ter but may be more prone to sticking. At maxi­mum setting, the arc will be more forceful and less
prone to sticking but will produce more spatter.
For TIG welding applications, this control should
usually be set to minimum.

4. CURRENT RANGE SELECTOR SWITCH (R3R-
400 and R3R-500 only): “A” position selects
lower range current control. “B” position selects
higher range current control.

5. OUTPUT CONTROL SWITCH (R3R OR REMOTE
POSITIONS): Selects the mode of control. In the
“R3R” position, control is by the machine control
panel. In the “Remote” position, control is through
an optional remote control device.

6. OUTPUT CONTROL POTENTIOMETER: Con-
trols current.

7. REMOTE CONTROL CONNECTION: The 6-pin
amphenol receptacle provides remote control con­nections. Machines below code 9500 use a termi­nal strip instead of the amphenol. A strain relief
connector is provided for cable entry.

OPERATION

B-4 B-4

IDEALARC R3R

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1. Power Source Pilot Light

2. ON/OFF Power Toggle Switch

3. Arc Force Control

4. Current Range Selector Switch (not on R3R-300)

5. Output Control Potentiometer

6. Output Control Switch (with R3R or Remote positions)

7. Remote Control Connections (6-pin amphenol or terminal strip)

8. Polarity Switch (optional)

9. DC Ammeter (optional)

10. DC Voltmeter (optional)

11. Thermal Protection Indicator Light

9

8

10

7

11

6

5

4

1

3

2

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OPERATION

B-5 B-5

IDEALARC R3R

8. POLARITY SWITCH (optional): Permits chang-

ing the electrode polarity of the output terminals
between DC+ and DC-.

9. DC AMMETER (optional): Displays output cur-

rent when welding.

10. DC VOLTMETER (optional): Displays output

voltage.

11. THERMAL PROTECTION INDICATOR LIGHT:

This amber light indicates that either of the two
protective thermostats has opened. Output
power is removed, but input power is still being
applied to the machine.

WELDING OPERATION

OPERATING STEPS

LOCAL CONTROL

The following procedures are for using the Idealarc
R3R in the local (“R3R”) control mode of operation.
For remote control of the machine, see the REMOTE
CONTROL section.

Before operating the machine, make sure you have all
materials needed to complete the job. Be sure you are
familiar with and have taken all possible safety pre­cautions before starting work. It is important that you
follow these operating steps each time you use the
machine.

1. Turn on the main AC input power to the machine.

2. Set the ELECTRODE POLARITY switch to the
appropriate position (optional if equipped).

3. Set the OUTPUT CONTROL switch to “R3R.”

4. Set the ARC FORCE CONTROL to midrange, 5-6,
for CC stick or TIG welding. Adjust for best char­acteristics as necessary.

5. Set the ON/OFF POWER toggle switch to the ON
position (1).

• The white power source pilot light glows.

• The fan starts.

6. Set the CURRENT RANGE SELECTOR switch to
the appropriate position (“A” for higher range, “B”
for lower range).

7. Set OUTPUT CONTROL potentiometer to desired
current.

8. Make the weld.

REMOTE CONTROL

The toggle switch on the control panel labeled “Output
Control Remote” gives you the option of controlling
the machine output from a remote location. In the
“Remote” position a remote control device such as a
K857 must be connected to the Idealarc R3R. Refer to
the Accessories section for available remote control
information.

POCKET AMPTROL (Optional)

The pocket amptrol option provides a remote current
control for the R3R welders. This “wireless” control
requires no control cable connection to the welder.
Use it as follows:

a. On the R3R-400 and -500 the welder CURRENT

CONTROL switch must be in the “Remote” posi­tion and the CURRENT RANGE SELECTOR switch
in the “B” range. The R3R-300 does not have a
CURRENT RANGE SELECTOR switch. With the
CURRENT CONTROL switch in the “Remote” posi­tion, the OUTPUT CONTROL potentiometer on the
welder is removed from the circuit and its setting
has no effect on the ouput. With the CURRENT
RANGE SELECTOR switch in the “B” range posi­tion, the pocket amptrol provides total control from
minimum to maximum output of the welder.

b. Turn the welder POWER switch ON.

c. Insert one end of the probe into the electrode hold-

er and hold the other end on the work for approxi­mately five seconds.

d. To change current, change the probe dial setting

and repeat the five second procedure of placing
the probe between electrode and work.

The solid state circuitry within the welder senses this
change in probe setting and automatically resets the
welding current to the new level. Each time the welder
is turned off, the output goes to minimum and must be
reset when the welder is turned on again.

OPERATION

B-6 B-6

IDEALARC R3R

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TABLE OF CONTENTS

- ACCESSORIES SECTION -

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

Options/Accessories...................................................................................................................C-2

Factory Installed Options .....................................................................................................C-2

Polarity Switch ...............................................................................................................C-2

Meters ............................................................................................................................C-2

Pocket Amptrol ..............................................................................................................C-2

Field Installed Options .........................................................................................................C-2

Remote Output Adapter Cable (K857)...........................................................................C-2

Accessory Kits (K703, K704) .........................................................................................C-2

Undercarriages (K817P, K841) .......................................................................................C-2

TIG Welding Options............................................................................................................C-2

TIG Module (K930-1)......................................................................................................C-2

Water Valve Kit (K844-1) ................................................................................................C-2

Amptrols (K870, K812, K963-1, K963-2) .......................................................................C-2

Contactor Kit (K938-1) ...................................................................................................C-2

Docking Kit (K939-1)......................................................................................................C-2

Control Cable (K936-3) ..................................................................................................C-2

Control Cable Extensions (K937-22.5, K937-45)...........................................................C-2

Section C-1 Section C-1

IDEALARC R3R

OPTIONS/ACCESSORIES

FACTORY INSTALLED OPTIONS

POLARITY SWITCH

Permits changing polarity at the machine output ter­minals.

METERS

Ammeter and Voltmeter.

POCKET AMPTROL

Provides a wireless remote current control for R3R
welders. See the Operation section for details.

FIELD INSTALLED OPTIONS

The following options/accessories are available for
your Idealarc R3R from your local Lincoln Distributor.

Remote Current Control (K857) - Portable current
control provides the same dial range as the current
control on the welder. Consists of a 6-pin Amphenol
connector which plugs into the remote control
Amphenol.

Accessory Kits (For R3R-300 and R3R-400) ­Consists of electrode and work cables, headshield,
electrode holder and work clamp.

R3R-300 - K703
R3R-400 - K704

Undercarriage (K817P) - A mounting frame with

wheels for hand moving.
Undercarriage (K841) - Platform undercarriage with

mountings for two gas cylinders at rear of welder.

TIG WELDING OPTIONS

TIG Module (K930-2) - Portable, high frequency unit

with gas valve for TIG welding. Rated at 300
amps/60% duty cycle. (Request publication E3.205)

Water Valve Kit (K844-1) - For use with a water­cooled TIG torch. Controlled by the preflow and after­flow timers. Installs inside the TIG module.

Amptrol™ - Provides 25 ft. (7.6m) of remote current
control for TIG welding. (6 pin MS-type plug connec­tion).

Foot Amptrol - K870
Hand Amptrol - K963-1
Hand Amptrol - K963-2

Contactor Kit (K938-1) - For use with the TIG Module.
Docking Kit (K939-1) - Secures TIG Module on top of

R3R machines, or any flat surface at least 10 in x 15 in
(254mm x 381mm). Mounts using strong grip adhe­sive pad or fasteners. Includes latch and provisions
for a user-supplied padlock.

Control Cable (K936-3) - Connects the TIG Module to
the R3R machine (9 to 6 plus 115V plug).

Control Cable Extensions - Allows the TIG Module to
be operated at distances up to 200 ft. (61m) from the
power source. Two lengths are available: 22.5ft.(6.9m)
or 45ft. (13.7m).

22.5 ft. - K937-22.5
45 ft. - K937-45

ACCESSORIES

C-2 C-2

IDEALARC R3R

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Section D-1 Section D-1

IDEALARC R3R

TABLE OF CONTENTS

- MAINTENANCE SECTION -

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

Safety Precautions......................................................................................................................D-2

Routine and Periodic Maintenance ............................................................................................D-2

General Component Locations...................................................................................................D-3

SAFETY PRECAUTIONS

ELECTRIC SHOCK can kill.

• Only qualified personnel
should perform this mainte­nance.

• Turn the input power OFF at
the disconnect switch or fuse
box before working on this
equipment.

• Do not touch electrically hot parts.

ROUTINE AND PERIODIC
MAINTENANCE

Perform the following daily:

1. Check that no combustible materials are around
the machine or in the welding or cutting area.

2. Remove any debris, dust, dirt, or materials that
could block cooling air flow to the machine.

3. Inspect the electrode cables for any slits or punc­tures in the cable jacket. Also check for any other
condition that could affect the proper operation of
the machine.

Perform periodically:

1. In extremely dusty conditions, dirt may clog the
cooling air channels, causing the machine to run
hot. Blow out the machine at regular intervals with
low pressure air. Clean the following parts. See

Figure D.1.

• Main transformer and choke

• SCR/diode bridge

• Control PC board

• Electrode and work cable connections

• Fan assembly

NOTE: The fan motor has sealed bearings that require
no service.

• Remote control terminal strip TS1 (in machines

below code 9500).

NOTE: Keeping remote control terminal strip TS1
clean is especially important in damp locations.

2. Pocket Amptrol Maintenance - Clean and maintain
the optional Pocket Amptrol (if equipped). Keep
the probe tip in good condition. It requires sharp
edges to penetrate heavy oxide coatings on the
work piece. A blunted tip could result in different
welding currents for a given dial setting.

MAINTENANCE

D-2 D-2

IDEALARC R3R

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WARNING

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MAINTENANCE

D-3 D-3

IDEALARC R3R

11

12

10

9

8

7

65

4

3

2

1

13

FIGURE D.1 – GENERAL COMPONENT LOCATIONS

1. CONTROL PANEL

2. SCR/DIODE BRIDGE

3. MAIN TRANSFORMER

4. CHOKE

5. RECONNECT PANEL (LOCATION)

6. INPUT CONTACTOR (LOCATION)

7. FAN ASSEMBLY

8. CONTROL TRANSFORMER (LOCATION)

9. PC BOARDS (LOCATION)

10. CASE FRONT

11. OUPUT TERMINALS
(LOCATION BENEATH HINGED PANEL)

12. POCKET AMPTROL (OPTIONAL)

13. POLARITY SWITCH (OPTIONAL)

NOTES

D-4 D-4

IDEALARC R3R

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Section E-1 Section E-1

IDEALARC R3R

TABLE OF CONTENTS

- THEORY OF OPERATION SECTION -

Theory of Operation .............................................................................................................Section E

General Description ....................................................................................................................E-2

Input Line Voltage, Contactor and Main Transformer.................................................................E-2

Output Mode and Control, Rectification and Feedback ............................................................E-3

Optional Polarity Switch and Amptrol Circuits ...........................................................................E-4

Protective Devices and Circuits..................................................................................................E-5

SCR Operation............................................................................................................................E-6

CONTROL BOARD

OUTPUT

CONTROL

ARC FORCE

CONTROL

CONTROL

TRANSFORMER

POWER

SWITCH

R
E
C
O
N
N
E
C
T

INPUT

CONTACTOR

TRANSFORMER

MAIN

SCR DIODE

HYBRID BRIDGE

/

SHUNT

OUTPUT

CHOKE

NEGATIVE

OUTPUT

TERMINAL

POSITIVE

OUTPUT

TERMINAL

G

A
T
E

S

I
G
N
A
L

S

FEEDBACK

F
E
E
D
B
A
C
K

THERMOSTATS

FAN

MOTOR

TERMINAL

STRIP

REMOTE

SWITCH

DIAL

SELECTOR

SWITCH

SNUBBER

BOARD

AMPHENOL

POLARITY

SWITCH

OPTIONAL

OPTIONAL

POCKET

AMPTROL

PC BOARD

OPTIONAL
POCKET
AMPTROL

TRANSFORMER

FIGURE E.1 – IDEALARC R3R BLOCK LOGIC DIAGRAM

GENERAL DESCRIPTION

The Idealarc R3R welder is a three-phase transformer
rectifier type constant current power source designed
for DC manual welding and air carbon arc cutting. Its
power system is SCR controlled with solid state elec­tronic circuitry. Minimum to maximum output is
obtained with a single potentiometer control.

INPUT LINE VOLTAGE,
CONTACTOR AND MAIN
TRANSFORMER

The desired three-phase input power is connected to
the R3R through an input contactor, located in the
input box at the rear of the machine. Two phases of
the input line are also connected to the primary of the

control transformer. The secondary of the control
transformer supplies 120VAC power, via the power
switch and thermostats, to activate the input contac­tor.

A reconnect panel allows the user to configure the
machine for the desired input voltage. This AC input
voltage is applied to the primary of the main trans­former.

The transformer changes the high voltage, low current
input power to a lower voltage, higher current output.
The finishes or “neutrals” of the main secondary coils
are connected together, and the three starts of the
secondary windings are connected to the rectifier
bridge assembly. In addition, three 66VAC phase
angle windings are housed in the main transformer
assembly. These windings provide power and “timing”
for the control board. Two of these coils provide
120VAC for the fan motor.

THEORY OF OPERATION

E-2 E-2

IDEALARC R3R

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FIGURE E.2 – INPUT LINE VOLTAGE, CONTACTOR AND MAIN TRANSFORMER

NOTE: Unshaded areas of Block Logic Diagram are the subject of discussion.

CONTROL BOARD

OUTPUT

CONTROL

ARC FORCE

CONTROL

CONTROL

TRANSFORMER

POWER

SWITCH

R
E
C
O
N
N
E
C
T

INPUT

CONTACTOR

TRANSFORMER

MAIN

SCR DIODE

HYBRID BRIDGE

/

SHUNT

OUTPUT

CHOKE

NEGATIVE

OUTPUT

TERMINAL

POSITIVE

OUTPUT

TERMINAL

G

A
T
E

S
I
G
N
A
L
S

FEEDBACK

F
E
E
D
B
A
C
K

THERMOSTATS

FAN

MOTOR

TERMINAL

STRIP

REMOTE

SWITCH

DIAL

SELECTOR

SWITCH

SNUBBER

BOARD

AMPHENOL

POLARITY

SWITCH

OPTIONAL

OPTIONAL

POCKET

AMPTROL

PC BOARD

OPTIONAL
POCKET
AMPTROL

TRANSFORMER