Lincoln Electric SP-255 User Manual

IM533

RETURN TO MAIN MENU

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.

NOT INSTALL, OPERATE OR
REPAIR THIS EQUIPMENT
WITHOUT READING THIS
MANUAL AND THE SAFETY
PRECAUTIONS CONTAINED
THROUGHOUT.

importantly, think before you act
and be careful.

And, most

DO

IDEALARC SP-255

For use with machine Code Numbers

10164, 10165

June, 1998

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

OPERATOR’S MANUAL

• Sales and Service through Subsidiaries and Distributors Worldwide •

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

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.

Mar ‘95

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.

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 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.

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.

5.b.

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.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.

Mar ‘95

vapors

to

iii

SAFETY

iii

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.

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.

Remember that welding sparks and hot

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.

Mar ‘95

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 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 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 s’applicuent aussi au pistolet de
soudage.

zones où l’on pique le laitier.

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

7. Quand on ne soud
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 le 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 autres 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 fumeés toxiques.

10. Ne pas souder en présence de vapeurs de chlore provenant
d’opérations 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 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.

e pas, poser la pince à une endroit isolé de

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 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 rayonnement de
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 laitier en fusion sont émises de l’arc de
soudage. Se protéger avec des 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

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, I’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 dispositifs de sûreté à leur
place.

Mar. ‘93

for selecting a QUALITY product by Lincoln Electric. We want you

Thank You

to take pride in operating this Lincoln Electric Company product

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

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.

Model Name & Number _____________________________________

Code & Serial Number _____________________________________

Date of Purchase _____________________________________

Whenever you request replacement parts for or information on this equipment always supply the information
you have recorded above.

vv

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:

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.

MASTER TABLE OF CONTENTS FOR ALL SECTIONS

Page

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

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

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

Uncrating the SP-255 ............................................................................................A-2

Location .................................................................................................................A-2

Input Power, Grounding and Connection Diagrams ..............................................A-2

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

Gun and Cable Installation ....................................................................................A-3

Shielding Gas .......................................................................................................A-4

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

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

Product Description ...............................................................................................B-2

Recommended Processes and Equipment ...........................................................B-2

Welding Capability.................................................................................................B-2

Limitations..............................................................................................................B-2

Description of Controls and Keys ..........................................................................B-2

Gun Switches.......................................................................................................B-10

Wire Drive Roll.....................................................................................................B-10

Procedure for Changing Drive Roll......................................................................B-10

Wire Reel Loading ...............................................................................................B-10

Mounting of 10 to 44 lbs. Spools .........................................................................B-11

To Start the Welder..............................................................................................B-11

Feeding Electrode................................................................................................B-11

Idle Roll Pressure Setting ....................................................................................B-11

Making a Auto Mode Weld...................................................................................B-12

Spot Weld Mode ..................................................................................................B-13

Stitch Weld Mode.................................................................................................B-13

Avoiding Wire Feeding Problems ........................................................................B-13

Fan Control..........................................................................................................B-13

Input Line Voltage Protection...............................................................................B-13

Wire Feed Overload Protection ...........................................................................B-13

Welding Thermal Overload Protection.................................................................B-14

Overcurrent Protection.........................................................................................B-14

Explanation of Prompting and Error Messages ...................................................B-14

vi

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

Drive Roll Kits........................................................................................................C-1

Aluminum Feeding Kit (optional K673-1)...............................................................C-1

8" Spool Adapter (K468)........................................................................................C-1

Dual Cylinder Mounting Kit (K671-1).....................................................................C-1

Spool Gun Description...........................................................................................C-1

Spool Gun Adapter Kit (optional K672-1) ..............................................................C-1

Making a Weld with the Spool Gun Adapter Kit and Spool Gun Installed .............C-1

(continued)

APR96 IDEALARC SP-255

vii

MASTER TABLE OF CONTENTS FOR ALL SECTIONS

Page

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

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

General Maintenance ............................................................................................D-1

Drive Rolls and Guide Tubes.................................................................................D-1

Gun Tubes and Nozzles........................................................................................D-1

Cable Cleaning......................................................................................................D-1

Contact Tip and Gas Nozzle Installation ...............................................................D-1

Liner Removal and Replacement ..........................................................................D-2

Gun Handle Disassembly......................................................................................D-3

Magnum 250SP Gun Parts and Accessories ........................................................D-3

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

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

Troubleshooting Guide ..........................................................................................E-2

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

Wiring Diagram L9688 (208/230V) ........................................................................F-1

Wiring Diagram L9689 (230/460/575V) .................................................................F-2

Dimension Print M16352........................................................................................F-3

Parts Lists........................................................................................................Appendix

IDEALARC SP-255

INSTALLATION

TECHNICAL SPECIFICATIONS – IDEALARC®SP-255

INPUT – SINGLE PHASE ONLY

Standard Voltage/Frequency Input Current (@ Max Rated Output)

208/230/60 Hz 53/49 Amps

230/460/575 Hz 50/25/20 Amps

RATED OUTPUT

Duty

Cycle Amps Volts at Rated Amperes

35% 250 Amps 26 Volts
60% 200 Amps 28 Volts

100% 145 Amps 26 Volts

OUTPUT

A-1

Welding

Current Range Maximum Open Circuit Voltage Wire Speed Range

30-250 Amps 40 Volts 50-600 IMP (1.27-15.2 m/min)

RECOMMENDED INPUT CABLE AND FUSE SIZES

75C Copper Wire 75C Copper Wire

in Conduit in Conduit

Input Fuse or Input Ampere AWG (IEC) AWG (IEC)

Voltage/ Breaker Size Rating on Sizes Sizes

Frequency (Super Lag) Nameplate For lengths For lengths Ground Wire

up to 100 ft. exceeding 100 ft.

208 60 53 8 (10 mm2) 6 (16 mm2) #10 (6 mm2)
230 60 50 10 (6 mm2) 8 (10 mm2) #10 (6 mm2)
460 30 25 14 (2.5 mm2) 12 (4 mm2) #10 (6 mm2)
575 25 20 14 (2.5 mm

2

) 12 (4 mm2) #10 (6 mm2)

PHYSICAL DIMENSIONS

Height Width Depth Weight

28.2 in 18.8 in 40.1 in 222 Ibs
719 mm 480 mm 1019 mm 101 kg

OPERATING TEMPERATURE STORAGE TEMPERATURE

-20° C TO 40°C ±40°C

AUG 95 IDEALARC SP-255

A-2

INSTALLATION

Read entire Installation section before starting
installation.

SAFETY PRECAUTIONS

WARNING

ELECTRIC SHOCK can kill.

• Only qualified personnel should perform
this installation.

• Only personnel that have read and under­stood the SP-255 Operating Manual should
install and operate this equipment.

• Machine must be plugged into a receptacle
which is grounded per any national, local
or other applicable electrical codes.

• Turn the power switch on the SP-255 “off”
before connecting or disconnecting gun
and cable, output cables or other equip­ment.

UNCRATING THE SP-255

1. Before starting the installation, check with the local
power company if there is any question about
whether your power supply is adequate for the volt­age, amperes, phase, and frequency specified on
the welder nameplate. Also, be sure the planned
installation will meet the U.S. National Electrical
Code and local code requirements. This welder
may be operated from a single phase line or from
one phase of a two or three phase line.

2. Models that have multiple input voltages specified
on the nameplate (e.g., 208/230) are shipped con­nected for the higher voltage. If the welder is to be
operated on lower voltage, it must be reconnected
according to the instructions on the inside of the
removable panel near the top left side of the rear
panel. These instructions are repeated below:

Remove the staples from the bottom edge of the car­ton and lift off. Cut the tape securing the two rear
wheels to the wooden shipping pallet. Using a 1/2 inch
(or 13 mm) wrench or socket, remove the two screws
which attach the pallet to the bottom of the SP-255.

LOCATION

Locate the welder in a dry location where there is free
circulation of clean air into the louvers in the back and
out the front. A location that minimizes the amount of
smoke and dirt drawn into the rear louvers reduces
the chance of dirt accumulation that can block air pas­sages and cause overheating.

INPUT POWER AND GROUNDING
CONNECTIONS

WARNING

ELECTRIC SHOCK can kill.

• Do not touch electrically live parts such as

output terminals or internal wiring

•

All input power must be electri­cally disconnected before
proceeding.

WARNING

Make certain that the input power is electrically
disconnected before removing the screw that
holds the removable rear panel in place.

3. The 208/230 volt 60 Hz model SP-255 is shipped
with a 10 ft. (3.0 m) input cable and plug connected
to the welder. A matching receptacle is supplied
with the machine. Mount the receptacle in a suit­able location using the screws provided. Be sure it
can be reached by the plug on the input cable
attached to the welder. Mount with the grounding
terminal at the top to allow the power cable to hang
down without bending.

IDEALARC SP-255 OCT94

INSTALLATION

A-3

The 230/460/575 volt 60 Hz model is not equipped
with a plug, input cable or receptacle.

4. Using the following instructions have a qualified
electrician connect the receptacle or cable to the
input power lines and the system ground per the
U.S. National Electrical Code and any applicable
local codes. See the “Technical Specifications”
page at the beginning of this chapter for proper
wire sizes. For long runs over 100 feet (30 m), larg­er copper wires should be used. Fuse the two hot
lines with super lag type fuses as shown in the fol­lowing diagram. The center contact in the recepta­cle is for the grounding connection. A green wire in
the input cable connects this contact to the frame
of the welder.

This ensures proper grounding of the welder frame
when the welder plug is inserted into the
receptacle.

SINGLE PHASE INPUT SUPPLY RECONNECT DIAGRAM FOR 230/460/575 60 HZ MACHINES

WARNING

HIGH VOLTAGE
can kill

1. ALL MACHINES ARE SHIPPED FROM THE FACTORY CONNECTED FOR THE HIGHEST NAMEPLATED SINGLE PHASE
INPUT VOLTAGE. TO CHANGE CONNECTIONS FOR A DIFFERENT INPUT VOLTAGE. RECONNECT BOTH COPPER
JUMPERS PER DIAGRAM BELOW. ALWAYS CONNECT JUMPERS BETWEEN OUTER STEEL NUT AND
INNER BRASS NUT ON TERMINAL STUDS.

2. CONNECT THE INPUT POWER TO THE INPUT TERMINAL BLOCK, L1 AND L2 AT THE UPPER LEFT CORNER OF
THE PANEL. TORQUE TO 16 IN-LBS.

3. CONNECT A GROUNDING LEAD TO THE GROUND STUD ON THE MACHINE NEAR THE INPUT TERMINAL BLOCK.

SINGLE PHASE
VOLTAGE

JUMPER

CONNECTION

DIAGRAMS

TURN THE INPUT POWER OFF AT THE DISCONNECT SWITCH BEFORE INSTALLING
OR SERVICING THIS MACHINE.
DO NOT TOUCH ELECTRICALLY "HOT" PARTS SUCH AS OUTPUT TERMINALS
OR INTERNAL WINDINGS.

GROUNDING SCREW
NATIONAL ELECTRICAL CODE.
DO NOT OPERATE WITH COVERS REMOVED.

ONLY QUALIFIED PERSONNEL SHOULD INSTALL OR SERVICE THIS EQUIPMENT.

230V / 60HZ. 460V. / 60HZ.

L1

L2

1

TO GROUND PER NATIONAL ELECTRICAL CODE

SINGLE PHASE INPUT POWER SUPPLY LINES

MUST BE CONNECTED TO A GOOD EARTH GROUND PER

L1

L2

5

2

4

3

4

1

3

CONNECT TO A SYSTEM GROUND­ING WIRE. SEE THE UNITED STATES
NATIONAL. ELECTRICAL CODE
AND/OR LOCAL CODES FOR OTHER
DETAILS AND MEANS FOR PROPER
GROUNDING.

CONNECT TO HOT WIRES OF A
THREE-WIRE, SINGLE PHASE SYS­TEM OR TO ONE PHASE OF A TWO
OR THREE PHASE SYSTEM.

575V. / 60HZ.

L1

5

2

L2

4

1

BOTH
JUMPERS

5

2

3

S21531-1

OUTPUT POLARITY CONNECTION

WARNING

Turn the welder power switch off before changing
output connection.

The welder, as shipped from the factory, is connected
for electrode positive (+) polarity. This is the normal
polarity for GMA welding.

If negative (–) polarity is required, interchange the
connections of the two cables located in the wire drive
compartment near the front panel. The electrode
cable, which is attached to the wire drive, is to be con­nected to the negative (–) labeled terminal and the
work lead, which is attached to the work clamp, is to
be connected to the positive (+) labeled terminal.

GUN AND CABLE INSTALLATION

The Magnum™ 250SP gun and cable provided with
the SP-255 is factory installed with a liner for .035­.045" (0.9-1.2 mm) electrode and an .035" (0.9 mm)
contact tip. Install the .045 tip (also provided) if this
wire size is being used. For other wire sizes, see Gun
and Cable Maintenance.

WARNING

Turn the welder power switch off before installing
gun and cable.

1. Lay the cable out straight.

2. Make sure all pins on the gun cable connector are
aligned with the proper mating sockets on the front
panel gun connector and then join the connectors
and tighten the hand nut on the gun cable connec­tor.

NOTE: If a gun and cable other than the Magnum
250SP is to be used, it must conform to standard
European-style connector (Magnum Fast-Mate™)
specifications. See diagram below.

IDEALARC SP-255

A-4

INSTALLATION

Gun - END VIEW

However, the thumbswitch functions available on
the Magnum 250SP gun will only be operable from
the front panel keypad. The gun trigger switch must
be capable of switching 5 milliamps at 15 volts
DC– resistive.

3. Stand to one side away from the outlet and open
the cylinder valve for an instant. This blows away
any dust or dirt which may have accumulated in the
valve outlet.

WARNING

Be sure to keep your face away from the valve
outlet when “cracking” the valve.

4. Inspect the regulator for damaged threads, dirt,
dust, oil or grease. Remove dust and dirt with a
clean cloth.

CAUTION

The gun trigger switch connected to the gun trig­ger control cable must be a normally open,
momentary switch. The terminals of the switch
must be insulated from the welding circuit.
Improper operation of or damage to the SP-255
might result if this switch is common to an electri­cal circuit other than the SP-255 trigger circuit.

SHIELDING GAS

(For Gas Metal Arc Welding Processes)

Customer must provide cylinder of appropriate type
shielding gas for the process being used.

WARNING

CYLINDER may explode if
damaged.

Gas under pressure is explosive.
Always keep gas cylinders in an

upright position and always keep
chained to undercarriage or stationary support.
See American national Standard Z49.1, “Safety in
Welding and Cutting” published by the American
Welding Society.

1. Set gas cylinder in rear platform of SP-255. Hook

chain in place to secure cylinder to rear of welder.

DO NOT USE THE REGULATOR IF OIL,
GREASE OR DAMAGE IS PRESENT! Have an
authorized repair station clean the regulator or
repair any damage.

5. Attach the flow regulator to the cylinder valve and
tighten the union nut(s) securely with a wrench.

NOTE: If connecting to 100% CO
regulator adapter provided between regulator and
cylinder valve. If adapter is equipped with a plastic
washer, be sure it is seated for connection to the
CO

cylinder.

2

6. Attach one end of the inlet gas hose to the outlet
fitting of the flow regulator, the other end to the SP­255 rear fitting, and tighten the union nuts securely
with a wrench.

7. Before opening the cylinder valve, turn the regula­tor adjusting knob counter-clockwise until the
adjusting spring pressure is released.

8. Open the cylinder valve slowly a fraction of a turn.
When the cylinder pressure gauge pointer stops
moving, open the valve fully.

cylinder, insert

2

WARNING

Never stand directly in front of or behind the flow
regulator when opening the cylinder valve. Always
stand to one side.

2. Remove the cylinder cap. Inspect the cylinder
valves for damaged threads, dirt, dust, oil or
grease. Remove dust and dirt with a clean cloth.

DO NOT ATTACH THE REGULATOR IF OIL,
GREASE OR DAMAGE IS PRESENT! Inform your
gas supplier of this condition. Oil or grease in the
presence of high pressure oxygen is explosive.

IDEALARC SP-255 OCT94

9. The flow regulator is adjustable. Set it for the flow
rate recommended for the procedure and process
being used before making the weld.

OPERATION

Read entire Operation section before
operating the SP-255.

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.

B-1

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.

Observe all safety information throughout
this manual.

IDEALARC SP-255

B-2

OPERATION

PRODUCT DESCRIPTION

The SP-255 is a complete semiautomatic constant
voltage DC arc welding machine built to meet NEMA
specifications. It combines a constant voltage power
source and a constant speed wire feeder with a micro­computer-based controller. This forms an intelligent
welding system that really puts the automatic in semi­automatic. A touch key entry system with audible
feedback, along with a two-line, 32 character alphanu­meric display provide user friendly control of the sys­tem.

Multilingual display capability allows the SP-255 to
communicate with the user in any of the following lan­guages: English, German, French, Spanish, or
Japanese (Katakana).

RECOMMENDED PROCESSES AND
EQUIPMENT

The SP-255 is recommended for GMA welding
processes using 10 to 44 lb. (4.5 to 20 kg) 2" (51 mm)
I.D. spools or Readi-Reel
(0.6-1.2 mm) solid steel using CO2, ArCO2, or ArO
shielding gas, .035" (0.9 mm) stainless steel using
ArO2or HeArCO2shielding gas, 3/64" (1.2 mm) alu­minum using Ar shielding gas, and .045" (1.2 mm)
Outershield
gas, as well as .035" (0.9 mm) and .045" (1.2 mm)
Innershield®self-shielded electrodes.

®

electrodes using CO2or ArCO2shielding

®

coils of .025 through .045

DESCRIPTION OF CONTROLS AND
KEYS

POWER SWITCH

Place the lever in the “ON” position to turn the SP-255
on. When the power is on, the red LED backlighting of
the LCD display will be lit, and the screen will contain
a readable display. The welding setup present when
the power was shut off or disconnected will be
restored when the power is restored.

SETUP KEYS

DISPLAY LANGUAGE SELECTION

The SP-255 has multilingual display capability permit­ting the SP-255 prompts, messages, and other display
information to be in any of five languages: English,
German, French, Spanish, and Japanese (Katakana).
The user may select the chosen language by simulta­neously pressing the PROCESS Key and the appro­priate Number Key per the instructions given in the
appropriate language on the Keypad Instruction Decal
inside the SP-255 door, also shown below:

2

The SP-255 is factory equipped to feed .035" (0.9
mm) and .045" (1.2 mm) electrodes and includes a
200A, 60% duty cycle rated, 12.5 ft. (3.8 m) GMA gun
and cable assembly equipped for these wire sizes.
The SP-255 is factory equipped with an adjustable
CO

and Argon blend flow regulator. A supply of

2

shielding gas is required for GMAW processes.

WELDING CAPABILITY

The SP-255 is rated at 250 amps @ 26 volts at a 35%
duty cycle on a ten minute basis. It is capable of high­er duty cycles at lower output currents.

LIMITATIONS

The SP-255 may not operate as designed if powered
with a portable or in-plant generator.

ARROW KEYS

There are three pairs of arrow keys: left, center, and
right. The up arrow keys increase the selection dis­played directly above them. The down arrow keys
decrease the selection displayed directly above them.
All of the arrow keys have a repeat function when they

IDEALARC SP-255

OPERATION

are held closed. The left pair will automatically contin­ue to increment or decrement the selection above it at
a slow, steady rate as long as the key is pressed. The
center and right pairs will continue to increment and
decrement the selections above them at a slow rate,
but then the rate will gradually increase until it
becomes very rapid. This allows rapid setting from a
small quantity to a large quantity or vice versa while
maintaining an excellent resolution (i.e., 50 IPM to 600
IPM). However, when the trigger is closed, the
changes will be at a steady, moderate rate to allow for
proper “on the fly” control.

START MODE SELECTIONS

The SP-255 permits selection of Fast/Slow Run-In
wire feed speed as well as adjustment of the start
striking voltage, to optimize arc starting, using the
starting screen display.

The starting screen (see Figures below) is
displayed by pressing and holding both the
PROCESS key and the TIMERS OFF key at
the same time.

B-3

3. Spool Gun Start Mode

If using optional spool gun mode (see “Making
a Weld with the Spool Gun” in Accessories sec­tion), the RUN-IN portion of the starting screen
is not functional and will not be displayed. The
START voltage is adjusted as described above
(Figure 3).

FIGURE 3

The starting screen is exited by pressing any
key on the keypad except TIMERS OFF, IPM­VOLTS or any Arrow key. Closing Gun Trigger
will also not clear the starting screen.

NOTE: It is not necessary to repeat the above
procedure each time the unit is powered up.
That is, the unit will remember the start mode
settings from the previous power down and
return you to that same state upon your next
power up. thus, you need only perform the
above procedure when you want to change the
start mode settings.

FIGURE 1

1. Run-In Speed

The SP-255 is factory set for FAST run-in
(Figure 1) where the wire feed will accelerate
directly to the preset speed. SLOW run-in will
initially feed at 50 IPM until welding current is
sensed, or for 2 seconds if feeding without
welding (loading wire).

SLOW run-in may be selected using the left
arrow keys which will toggle the starting screen
display to SLOW (Figure 2) or back to FAST
(Figure 1).

FIGURE 2

2. Start Voltage

The START voltage setting (Figure 1 or 2) may
be offset from the factory programmed level
(00%) by up to ±30% above or below pro­grammed level using the right arrow keys, or
from the gun thumbswitch by positioning the
screen cursor beneath the START display using
the IPM-VOLTS key. (see “Gun Switch Keys” in
this section).

When saving to Memory locations 1-5, the start
mode at the time of saving will be saved into
the memory location as well. Thus, the operator
should be aware that when recalling a memo­rized procedure, he is also recalling particular
start mode which will override any present start
mode setting and remain in effect until either
the mode is changed using the above proce­dure or until a memorized procedure containing
another start mode is recalled.

PROCESS (WIRE/GAS) KEY

This key is used to display the Wire Type, Wire
Diameter, and Welding Gas. Each combination of wire
and gas dictates a unique relationship between the
wire feed speed and the arc voltage. The SP-255
uses this unique relationship, along with the metal
thickness, to set the proper values of wire feed speed
and arc voltage. Therefore, it is very important that

the wire type, wire diameter, and welding gas on
the display match the actual wire type, wire diame­ter, and welding gas being used for the weld.

Left arrow keys—set Wire Type

JAN96 IDEALARC SP-255

B-4

OPERATION

Center arrow keys—set Wire Diameter

Right arrow keys—set Welding Gas

The following 16 processes are programmed into the
SP-255:

Wire Type Wire Diameter Welding Gas

Solid Steel
Solid Steel
Solid Steel
Solid Steel
Solid Steel
Solid Steel
Solid Steel
Solid Steel
Solid Steel

Stainless
Stainless

Aluminum (5356)

Outershield
Outershield

Innershield
Innershield

®

®

.025 (0.6mm)
.025 (0.6mm)
.030 (0.8mm)
.030 (0.8mm)
.035 (0.9mm)
.035 (0.9mm)
.035 (0.9mm)
.045 (1.2mm)
.045 (1.2mm)

.035 (0.9mm)
.035 (0.9mm)

3/64” (1.2mm)

.045 (1.2mm)
.045 (1.2mm)

.035 (0.9mm)
.045 (1.2mm)

CO

2

ArCO

2

CO

2

ArCO

2

CO

2

ArCO

2

ArO

2

CO

2

ArCO

2

ArO

2

HeArCO

Argon

CO

2

Ar/CO

2

None
None

2

PROCEDURE KEYS

Because design, fabrication, assembly and
welding variables affect the results obtained in
applying recommended procedure information,
the serviceability of a product or assembly is
the responsibility of the builder/user.

available sizes. (NOTE: If the spot or stitch timers are

on, metal thickness is not displayed and, therefore,
the left arrow keys will not function. Also, the left arrow
keys do not function when the trigger is closed. (See
Figures I and 2 following.)

Center arrow keys — Increases (up arrow) or
decreases (down arrow) wire feed speed setting.
Increasing or decreasing wire feed speed will
simultaneously cause an increase or decrease in
the arc voltage and can change the metal thick­ness setting.

Right arrow keys — Increases (up arrow) or
decreases (down arrow) arc voltage setting. An up
arrow indicator appears below the V in VOLTS if
the arc voltage has been set higher than the rec­ommended value, and a down arrow indicator
appears below the V in VOLTS if the arc voltage is
below the recommended value. No arrow indicates
that you are set to the recommended value. (See
Figures 4 and 5 following.)

Repressing the Auto key resets the wire feed speed
and arc voltage settings to the recommended values
for the metal thickness displayed. (NOTE: If the spot
or stitch timers are on, metal thickness is not dis­played and, therefore, the repress function does not
work.)

AUTO KEY

Pressing the Auto Key once places the SP-255 into
the automatic mode of operation. Auto mode provides
automatic setup of the recommended wire feed speed
and arc voltage based on the metal thickness selected
and the process being used. The Auto mode screen
displays metal thickness, set wire feed speed, the set
arc voltage, and a cursor that indicates which parame­ter, wire feed speed, or arc voltage is being controlled
by the thumbswitch on the SP-255 gun (see Gun
Switches section).

Left arrow keys — Increases (up arrow) or
decreases (down arrow) metal thickness setting.
Increasing or decreasing metal thickness automati­cally increases or decreases both wire feed speed
and arc voltage simultaneously. See gauge chart
on instruction label on inside of SP-255 door for

Figure 4 Figure 5

TYPICAL AUTO KEY PRESS SEQUENCES

Process screen is being displayed prior to pressing
Auto key. The Auto key is pressed, the Auto screen is
now displayed.

If the unit was in a Manual configuration (see Manual
Key) when the Auto key was pressed, the audio alarm
will beep three times and a message (see below) will
be displayed for 2.5 seconds reminding you that the
process entered into the SP-255 (see Process Key)
must match the wire and gas being used. After the 2.5
second period is over, the Auto screen will be dis­played with the same procedure that was in Manual.

IDEALARC SP-255