background image

B-1

OPERATION

B-1

LF-74

COLD FEED

POSITIVE OUTPUT

NEGATIVE OUTPUT

PROTECTIVE
GROUND

WARNING OR
CAUTION

DANGEROUS
VOLTAGE

SHOCK
HAZARD

WELDING
FUMES

EXPLOSION

GAS INPUT

WORK 
CONNECTION

SAFETY PRECAUTIONS

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

ELECTRIC SHOCK can kill.

• Unless using cold feed feature,

when feeding with the gun trigger,
the electrode and drive mechanism
are always electrically energized
and could remain energized several
seconds after welding ceases.

• 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 PERSONS SHOULD INSTALL,
USE OR SERVICE THIS EQUIPMENT. READ AND
FOLLOW THE MANUFACTURER’S INSTRUC-
TIONS, EMPLOYER’S SAFETY PRACTICES AND
MATERIAL SAFETY DATA SHEETS (MSDS) FOR
CONSUMABLES.

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

READ THIS WARNING, PROTECT YOURSELF &
OTHERS.

FUMES AND GASES can be dangerous.

• Keep your head out of fumes.

• Use ventilation or exhaust at the

arc, or both,to keep fumes and
gases from your breathing zone and
general area.

WELDING SPARKS can cause fire or

explosion.

• Do not weld near flammable material.

• Do not weld on containers which have

held flammable material.

ARC RAYS can burn.

• Wear eye, ear, and body protection. 

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

Observe additional guidelines detailed in the
beginning of this manual.

WARNING

GRAPHIC SYMBOLS THAT APPEAR ON
THIS MACHINE OR IN THIS MANUAL

COMMON WELDING ABBREVIATIONS

WFS

• Wire Feed Speed

CV

• 

Constant Voltage

GMAW (MIG)

• Gas Metal Arc Welding

FCAW (Innershield or Outershield)

• 

Flux Core Arc Welding

ARC WELDING SUPPLIES - 07 847 7870

Summary of Contents for LF-74

Page 1: ...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 OPER ATE OR REPAIR THIS EQUIP MENT WITHO...

Page 2: ...H 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 A...

Page 3: ...usly 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 floo...

Page 4: ...ng 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...

Page 5: ...les 4 Des gouttes de laitier en fusion sont mises de l arc de soudage Se prot ger avec des v tements de protection libres de l huile tels que les gants en cuir chemise paisse pan talons sans revers et...

Page 6: ...he correct replacement parts On Line Product Registration Register your machine with Lincoln Electric either via fax or over the Internet For faxing Complete the form on the back of the warranty state...

Page 7: ...Model Bench Model and Extra Torque Bench Model A 18 Common Equipment Set Ups A 19 High Volume Production A 20 Portable Welding A 21 ___________________________________________________________________...

Page 8: ...ing E Safety Precautions E 1 How To Use Troubleshooting Guide E 1 Troubleshooting E 2 E 3 ________________________________________________________________________ Wiring Diagram and Dimension Prints S...

Page 9: ...m 32 0 Kg Duty Extra Torque WELDING CAPACITY RATING Amp Rating Duty Cycle 600 A 60 Model K2426 1 K2426 4 K2426 2 K2426 5 K2426 3 Model K2426 1 K2426 4 K2426 2 K2426 5 K2426 3 Gearing Normal Speed Norm...

Page 10: ...could remain energized several seconds after the gun trigger is released Welding power source must be connected to system ground per the National Electrical Code or any applicable local codes Only qu...

Page 11: ...g remove the wire reel stand if assembled and secure the wire feeder directly to the desired surface SUSPENDED Only suspend the wire feeder by the handle lift bail of the portability kit K2426 1 shown...

Page 12: ...cle 60 100 20 40 30 30 40 60 100 60 100 60 60 100 60 200 to 250 Ft 61 to 76 m 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 2 0 3 0 3 0 4 0 4 0 4 0 150 to 200 Ft 48 to 61 m 1 1 1 1 1 1 1 1 1 0 2 0 2 0 3 0 3 0 3 0 1...

Page 13: ...d by 8 small leads wrapped around one large lead The large inner lead connects to the electrode stud on the power source and the electrode connection on the wire feeder The small leads combine togethe...

Page 14: ...g Output Control 2 trigger from feeder D Welding Output Control 4 trigger from feeder E Remote Voltage Control 77 supply from feeder or remote F Remote Voltage Control 76 control signal from feeder or...

Page 15: ...M L WIRE FEEDER POWER SOURCE MILLER POWER SOURCE Pin Function A 24 VAC to feeder B Welding Output Control C 10VDC to feeder for remote control D Remote control common E 0 10VDC from feeder for remote...

Page 16: ...035S 035 0 9mm KP1505 040S 040 1 0mm KP1505 045S 045 1 2mm KP1505 052S 052 1 4mm KP1505 1 16S 1 16 1 6mm Welding Gun Wire Feeder Amphenol A B C D E Trigger Lead A 8 INSTALLATION LF 74 A 8 Drive Roll...

Page 17: ...m long Magnum Pro 350 gun and cable 1 Turn off power at the welding power source 2 Unscrew Thumb screw on Wire Drive Unit until tip of screw no longer protrudes into gun bushing hole as seen from the...

Page 18: ...t power OFF at the welding power source before instal lation or changing drive rolls and or guides Do not touch electrically live parts When inching with the gun trigger electrode and drive mechanism...

Page 19: ...ure arms 5 Remove the drive rolls and inner wire guide To install drive rolls and wire guides See Figure A 7 and A 7a 1 Turn off power at the welding power source 2 Open pressure arms 3 Assemble the i...

Page 20: ...ased Only qualified personnel should perform mainte nance work The pressure arm controls the amount of force the drive rolls exert on the wire Proper adjustment of both pres sure arm gives the best we...

Page 21: ...presence of high pressure oxygen is explosive 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 va...

Page 22: ...changing wire spool Only qualified personnel should install use or service this equipment Loading 10 to 15 lb 4 5 6 8kg Spools A K468 spindle adapter is required for loading 2 wide spools on 2 51mm s...

Page 23: ...that the force required to pull the wire from the reel into the wire drive unit is kept at a minimum b The electrode is hot when the gun trigger is pressed and must be insulated from the boom and str...

Page 24: ...ing assembly 3 Remove the six screws securing the wire drive panel to the sheet metal housing 4 Loosen the set screw on the feed plate and remove the incoming bushing FIGURE A 12a 5 Insert the conduit...

Page 25: ...scratching of the aluminum wire remove the ball bearings from the ball housing as follows Tools required See Figure A 12b 9 64 Hex key wrench 1 Turn off power at the welding power source 2 Remove the...

Page 26: ...INSTALLATION LF 74 A 18 BENCH MODEL WITH HEAVY DUTY WIRE STAND K2426 2 EXTRA TORQUE BENCH MODEL WITH HEAVY DUTY WIRE STAND K2426 3 BASE MODEL K2426 1 A R C W E L D I N G S U P P L I E S 0 7 8 4 7 7 8...

Page 27: ...iterature K586 1 K1557 1 K1803 1 K2400 1 Description LF 74 Bench Model with Heavy Duty Wire Reel Stand 035 045 0 9mm 1 2mm Drive Roll Kit 10 3m Control Cable Magnum Gun Deluxe Regulator for Mixed Shie...

Page 28: ...74 Base Model 035 045 0 9 1 2mm Drive Roll Kit 10 3m Control Cable Control Cable Extension Welding Gun Remote Voltage Control Kit Timer Kit Welding Arm Deluxe Gas Regulator for Mixed Gases Shielding...

Page 29: ...sit amet consec tetuer adipisc ing Lorem ipsum dolor sit amet consec tetuer adipisc ing elit ed diam nonum my nibh euismo d tincidu nt ut elit ed diam nonum my nibh euismo d tincidu nt ut laoree t do...

Page 30: ...SERVICE THIS EQUIPMENT READ AND FOLLOW THE MANUFACTURER S INSTRUC TIONS EMPLOYER S SAFETY PRACTICES AND MATERIAL SAFETY DATA SHEETS MSDS FOR CONSUMABLES READ THIS WARNING PROTECT YOURSELF OTHERS FUMES...

Page 31: ...ryday welding Powering the wire drive is a high perfor mance motor gearbox A heavy duty hinged door opens easily which provides an ample amount of room for assembling precision drive components and th...

Page 32: ...Overload 5 Cold Feed Gas Purge Switch press the switch up to feed wire with weld output off Press the switch down for gas flow with weld output off 6 2 step Trigger Interlock switch 7 Gun Receiver Bus...

Page 33: ...ps to condition the wire for the next weld To set the burnback time adjust the knob to approxi mately 0 03 seconds and then decrease or increase the time as desired Postflow Timer The postflow timer r...

Page 34: ...t when making long welds When the gun trigger is first pulled the welding power source energizes the output and the wire feeder feeds wire for welding The gun trigger is then released while the weld i...

Page 35: ...es Wire Reel Stand for up to 44 lbs 20 kg spools Spindle and mounting hard ware Includes Insulated lift bail and hardware Includes Swivel adapter and mounting hardware for attach ing to a power source...

Page 36: ...oln gun connec tors compatible with Miller guns Gun Receiver Bushing compatible with Oxo guns Includes 14 pin to 14 pin wire feeder to power source control cable Includes Adapter control cable for con...

Page 37: ...s to 2 in 51 mm spindles Readi Reel Adapter for mounting 50 60 lb 22 7 27 2 kg reels to 2 in 51 mm spindles For use with Heavy Duty Bench models Coil Adapter for mounting 50 60 lb 22 7 27 2 kg coils t...

Page 38: ...Heavy Duty Bench Models Light Duty Caster Kit for use with Heavy Duty Bench Models Insulated Lift Bail for use with Heavy Duty Bench Models Includes Cover backing plate wire conduit incoming bushing f...

Page 39: ...n the p c board potentiometer or motor is replaced or serviced Calibration matches the scale on the name plate to the actual wire feed speed To verify the wire feed speed 1 Assemble a 045 1 2 mm drive...

Page 40: ...short ing plug into the control p c board J2 shorts pins 1 and 5 See Figure D 2 and adjust WFS Knob to get 9 05 0 15 RPM and then remove shorting plug 6 Set WFS Knob to 300 IPM 7 Measure drive role R...

Page 41: ...the Recommended Course of Action safely contact your local Lincoln Authorized Field Service Facility HOW TO USE TROUBLESHOOTING GUIDE Service and Repair should only be performed by Lincoln Electric Fa...

Page 42: ...prob lems 5 Verify power is being supplied to the wire feeder 1 Verify the correct drive rolls and inner wire guide are installed in the wire drive 2 Check for sharp bends in the gun liner 3 Examine t...

Page 43: ...nd mixture 6 Verify the gun bushing is tightly mounted to the wire drive 7 Verify the gun is tightly mounted to the gun bushing 1 Check for sharp bends in the gun liner 2 Examine the contact tip for w...

Page 44: ...76 77 75 L2 L3 575 575C 575B INPUT ELECTRODE CABLE CONNECTION J1 J14 9 8 16 1 5 4 8 1 J2 606 606A 1B B B W 522 R U B 2 1 P6 4 3 L5 2 1 P4 4 3 L4 NORMAL SPEED HIGH TORQUE 551B 551A 551A 551B 521 522 52...

Page 45: ...achines covered by this manual The specific diagram for a particular code is pasted inside the machine on one of the enclosure panels If the diagram is illegible write to the Service Department for a...

Page 46: ...3 DIMENSION PRINTS F 3 LF 74 11 75 12 89 10 20 11 11 7 12 4 41 2 38 13 00 13 15 10 70 15 27 2 85 25 63 12 90 2 07 BENCH MODEL BENCH MODEL HEAVY DUTY A R C W E L D I N G S U P P L I E S 0 7 8 4 7 7 8 7...

Page 47: ...NOTES LF 74 A R C W E L D I N G S U P P L I E S 0 7 8 4 7 7 8 7 0...

Page 48: ...electrode with skin or wet clothing Insulate yourself from work and ground No toque las partes o los electrodos bajo carga con la piel o ropa moja da Aislese del trabajo y de la tierra Ne laissez ni...

Page 49: ...eitsplatzes Mantenha seu rosto da fuma a Use ventila o e exhaust o para remover fumo da zona respirat ria Turn power off before servicing Desconectar el cable de ali mentaci n de poder de la m quina a...

Page 50: ...iaries and Distributors Worldwide Cleveland Ohio 44117 1199 U S A TEL 216 481 8100 FAX 216 486 1751 WEB SITE www lincolnelectric com World s Leader in Welding and Cutting Products A R C W E L D I N G...

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