RETURN TO MAIN MENU IM502-A LN-742 & LN-742H Wire Feeders For use with machines having Code Numbers: June, 2000 10029 10030 10234 10235 10236 10237 10046 10047 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.
i i SAFETY 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 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 ARC WELDING CAN BE HAZARDOUS.
ii ii SAFETY 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.
iii iii SAFETY 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.
iv iv SAFETY 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.
v v Thank You for selecting a QUALITY product by Lincoln Electric. We want you to take pride in operating this Lincoln Electric Company product ••• as much pride as we have in bringing this product to you! Please Examine Carton and Equipment For Damage Immediately When this equipment is shipped, title passes to the purchaser upon receipt by the carrier.
vi TABLE OF CONTENTS Page Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i-iv Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section A Technical Specifications - LN-742 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1 Mounting Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2 Input Cable Connections . . . .
A-1 A-1 INSTALLATION TECHNICAL SPECIFICATIONS – LN-742 INPUT VOLTAGE 40 to 42V ±10%, 50/60 Hz, 4.0 Amps WIRE FEED SPEED SYSTEM WIRE SPEED RANGE LN-742 50 in. to 770 in. per minute (1.25 to 19.5 m/min) LN-742H 80 in. to 1200 in. per minute (2.00 to 30.5 m/min) WIRE DIAMETERS SYSTEM ELECTRODE DIAMETER LN-742 SOLID 0.025 in. through 1/16 in. (0.6 through 1.6 mm) LN-742H SOLID 0.025 in. through 0.045 in. (0.6 through 1.2 mm) LN-742 CORED 0.045 in. through 3/32 in. (1.2 through 2.
A-2 A-2 INSTALLATION MOUNTING LOCATION The LN-742 wire feeders can be mounted directly on top of the power source providing that it is secure and level. The LN-742 can also be mounted to an undercarriage when portability is required. The LN-742 should be installed upright on a horizontal surface. A K178-1 mounting platform is available for mounting the LN-742 to the top of Idealarc power sources. Refer to Section C, Accessories, for details.
A-3 A-3 INSTALLATION 4. Connect the remaining end of the control cable with the eight-socket cable plug to the mating receptacle on the LN-742. 5. Referring to Figure A.2, install the input cable under the wire reel mounting stand strain relief clamp. Remove the screws holding the clamp to the base of wire reel mounting assembly. Put the input cable under the clamp and reinstall the screws. FIGURE A.2 – STRAIN RELIEF CLAMP. CONTROL CABLE The connection diagram, Figure A.
A-4 A-4 INSTALLATION FIGURE A.3 – LN-742 WIRE FEEDER TO LINCOLN POWER SOURCE – CONNECTION DIAGRAM. WARNING TURN INPUT POWER OFF BEFORE CONNECTING THE LN-742 WIRE FEEDER.
A-5 INSTALLATION WORK CABLE Connect a work lead of sufficient size and length (Table A.1) between the proper output stud on the power source and the work. Be sure the connection to the work makes tight metal-to-metal electrical contact. TABLE A.1 – WORK LEAD SPECIFICATIONS Copper Work Cable Size, AWG Current 60% Duty Cycle 300 400 500 600 Amps Amps Amps Amps Up To 50 Ft (15.2 m) 50 Ft-100 Ft (15.2-30.
A-6 A-6 INSTALLATION WATER CONNECTIONS (FOR WATER COOLED GUNS) The LN-7 GMA must have a K590-1 Water Solenoid Kit installed (see Section C, Accessories). Refer to Figure A.4 and perform the following steps: The maximum water pressure permitted for use with the LN-742 is 55 psi (3.8 bar).
A-7 INSTALLATION GMAW SHIELDING GAS HOOKUP WARNING Gas under pressure is explosive. Always keep gas cylinders in an upright position and chained to the undercarriage or a stationary support. See American National Standard Z-49.1, “Safety In Welding And Cutting”, published by the American Welding Society.
B-1 OPERATION B-1 OPERATING INSTRUCTIONS GENERAL DESCRIPTION Read and understand the entire Operation Section prior to operating the machine. The LN-742 semiautomatic constant speed wire feeder is specifically equipped for gas metal arc welding using flux-cored Outershield electrodes and solid wire. The LN-742 is also suitable for self-shielded flux-cored Innershield electrodes, submerged arc welding (if constant voltage is satisfactory), and other open arc welding.
B-2 OPERATION • 0.045 to 5/64 in. (1.2 to 2.0 mm) cored wire for Innershield processes. The LN-742H is capable of the following wire feed ranges: • 0.025 to 0.045 in. (0.6 to 1.2 mm) solid wire for gasmetal-arc or CV submerged arc processes. • 0.045 in. (1.2 mm) cored wire for Outershield gasmetal-arc or Innershield processes. CONTROLS AND SETTINGS The operator controls are located on the keypad shown in Figure B.1.
B-3 OPERATION FUNCTION SELECTION CONTROLS. This control enables the operator to select the function that will be displayed as shown by the indicator lights. Pressing the key causes the mode lights to sequence (from top to bottom). Settings displayed in the LED display are adjusted using the setting adjustment arrows to the left of the LED display. The top light indicates the arc voltage is being displayed in volts. The middle light indicates the inch speed is being displayed.
B-4 B-4 OPERATION FIGURE B.2 – INSTALLING DRIVE ROLLS ON A TWO-ROLL FEEDER.
B-5 OPERATION 5. Use the clamping collar and hex head screw to install the roll on the output shaft. Certain size drive rolls consist of two roll halves, and may contain a spacer. If the drive roll you are installing contains a spacer, the spacer fits between the two halves of the drive roll. Double grooved drive rolls are to be installed with side stenciled for correct wire size facing outward and with slotted spacer on top of roll. Tighten the hex head screw. 6.
B-6 B-6 OPERATION FIGURE B.3 – INSTALLING DRIVE ROLLS ON A FOUR-ROLL FEEDER.
B-7 OPERATION 14. Slide the longer incoming guide tube into the rear hole of the gearbox until it almost touches the drive roll and guide tube. Tighten the thumbscrew to hold it in place. FIGURE B.4 – IDLE ROLL PRESSURE SETTING. 15. Be certain that the guide tubes do not touch the drive rolls or idle rolls. If they do touch, readjust them and tighten in place. 16. Close and latch both quick release levers. IDLE ROLL PRESSURE SETTING The idle roll pressure is set at the factory.
B-8 B-8 OPERATION WIRE LOADING 6) Set one of the Readi-Reel inside cage wires on the slot in the retaining spring tab. Loading a 22 to 30 Lb. (10 to 14 kg) Readi-Reel Package Using the Molded Plastic K363-P Readi-Reel Adapter: 7) Lower the Readi-Reel to depress the retaining spring and align the other inside cage wires with the grooves in the molded adapter. The Spindle should be located in the LOWER mounting hole of the K1524-1 Universal Stand if used.
B-9 TO MOUNT 10 TO 44 lb (4.5 to 20 kg) SPOOLS (12 in./300 mm DIAMETER) OR 13-14 lb (6 kg) INNERSHIELD COILS: The spindle should be located in the lower mounting hole of the K1524-1 Universal Stand if used. [For 8 in. (200 mm) spools, a K468 spindle adapter must first be slipped onto the spindle.] [For 13 to 14 lb (6 kg) Innershield coils, a K435 Coil Adapter must be used.] 2. While tightly holding the electrode, cut off the bent end and straighten the first six inches. Cut off the first inch.
B-10 B-10 OPERATION WIRE REEL LOADING – 50 AND 60 LB COILS (K303 OR K376 WIRE REEL STAND) ADJUSTABLE WIRE REEL BRAKE The mount for standard 50 and 60 pound electrode coils includes a two-position brake assembly. Generally the brake should be at the inner position (nearest to the wire reel shaft) for wire feed speeds below 400 in./min (10 m/min). It should be at the outer position for the faster wire speeds often used when feeding smaller diameter electrode.
B-11 B-11 OPERATION WIRE REEL LOADING – 50 AND 60 LB COILS (K1524-1 UNIVERSAL WIRE REEL STAND) FIGURE B.7 – K1504-1 COIL REEL. SPINNER NUT TO MOUNT A 50 to 60 lb (22.7 to 27.2 kg) COIL: (USING K1504-1 COIL REEL) (FOR 50 to 60 lb READI-REELS A K438 READI-REEL ADAPTER MUST BE USED.) COVER PLATE The spindle should be located in the UPPER mounting hole. SLOTS 1. With the K-1504-1 Coil Reel mounted on the 2 in.
B-12 OPERATION MAKING A WELD B-12 9. Position the electrode over the joint. The end of the electrode may be lightly touching the work. 1. Use only constant voltage power type sources. If using a multiple process power source, be sure it is set for constant voltage output per instructions in the manual for the power source. 2. Set the power source polarity switch or properly connect the electrodes and work leads for the correct electrode polarity. 3.
C-1 ACCESSORIES C-1 GENERAL The following is a list of the accessories that can be used with the LN-742 wire feeder. A detailed description of each item is given later in this section. TABLE C.1 – LN-7 GMA ACCESSORIES.
C-2 ACCESSORIES K163 UNDERCARRIAGE The undercarriage includes casters, wheels, a handle, and related hardware. Casters are mounted at the front and wheels at the rear of the platform. The handle is bolted to the front of the platform so the wire feeder can be tilted back and wheeled like a two-wheel truck. Installation sheet M13424 is provided with the undercarriage.
C-3 ACCESSORIES K320 FLUX TANK Either turn off the incoming air line or remove the quick disconnect if one has been installed. Slightly loosen the tank cap and let the air in the tank escape in the holes in the side of the cap. After pressure has been released, remove the cap from the tank. Using the funnel provided, put 100 pounds of flux in the tank. It is very important that only new or properly reclaimed flux be put in the tank.
C-4 ACCESSORIES SPINDLES, STANDS, AND ADAPTERS C-4 UNIVERSAL WIRE REEL STAND (K1524-1) There are a variety of spindles and wire reel adapters available for use with the LN-742. Select the desired setup according to your specific welding needs. K162H SPINDLE Includes a 2" (51mm) O.D. Spindle with adjustable brake and two locations for mounting the spindle to allow for the mounting of 50 - 60lb, 10 - 30 lb, 13 14lb, and 8" O.D. coils with proper spindle adapters.
C-5 ACCESSORIES K377 SMALL MOUNTING STAND FOR READI-REEL COILS AND 22 TO 30 LB SPINDLE WITH 2 IN. I.D. This assembly includes a wire reel spindle (similar to the K162 spindle) attached to a small frame. The unit is supplied with the K363 Readi-Reel Adapter for using the Lincoln “Readi-Reel Electrode Coils”. Without the adapter the unit is capable of handling spools with a 2 in. I.D., a 12 in. maximum O.D., and a 4 in. width. For spools with an 8 in. O.D., a K468 spindle adapter is available.
C-6 C-6 ACCESSORIES DRIVE ROLL KITS Table C-2 lists the appropriate drive roll kits for each type of wire used. TABLE C.2 – DRIVE ROLL KIT NUMBERS. 2-Roll Steel Wire Sizes 0.068-3/32 in. (1.7-2.4 mm) Cored 1/16 in. (1.6 mm) Cored or Solid 0.045-0.052 in. (1.2-1.3 mm) Solid 0.045-0.052 in. (1.2-1.3 mm) Cored 0.035 in. (0.9 mm) Solid 0.035 in. (0.9 mm) Cored 0.030 in. (0.8 mm) Solid 0.023-0.025 in. (0.6 mm) Solid Aluminum Wire Sizes* 1/16 in. (1.6 mm) 3/64 in. (1.2 mm) 0.035 in. (0.
D-1 MAINTENANCE ROUTINE MAINTENANCE D-1 No routine maintenance is required for Readi-Reels and 10 to 30 lb spools. Do not lubricate the 2 in. spindles. DRIVE ROLLS AND GUIDE TUBES After feeding every coil of wire, inspect the drive roll section. Clean the assembly as necessary. Do not use solvent to clean the drive roll assembly as it may wash the lubricant out of the bearings. The drive rolls and guide tubes are stamped with the wire sizes they will feed.
E-1 TROUBLESHOOTING E-1 HOW TO USE TROUBLESHOOTING GUIDE WARNING Service and Repair should only be performed by Lincoln Electric Factory Trained Personnel. Unauthorized repairs performed on this equipment may result in danger to the technician and machine operator and will invalidate your factory warranty. For your safety and to avoid Electrical Shock, please observe all safety notes and precautions detailed throughout this manual.
E-2 E-2 TROUBLESHOOTING Observe all Safety Guidelines detailed throughout this manual PROBLEMS (SYMPTOMS) POSSIBLE AREAS OF MISADJUSTMENTS(S) The display is blank. No wire feed when the gun trigger is activated. 1. Make sure the control cable is connected to the welding power source correctly. RECOMMENDED COURSE OF ACTION 2. Make sure the welding power source is turned on and functioning properly. 3. Check the 42 VAC fuse or circuit breaker in the welding power source.
E-3 E-3 TROUBLESHOOTING Observe all Safety Guidelines detailed throughout this manual PROBLEMS (SYMPTOMS) POSSIBLE AREAS OF MISADJUSTMENTS(S) When the gun trigger is activated the wire feed motor runs and the solenoid functions but no arc voltage is present. 1. Make sure the welding power source is functioning properly. Disconnect the control cable from the Lincoln power source. Place a jumper across sockets C and D of the 14 pin amphenol plug at the power source.
E-4 E-4 TROUBLESHOOTING Observe all Safety Guidelines detailed throughout this manual PROBLEMS (SYMPTOMS) POSSIBLE AREAS OF MISADJUSTMENTS(S) The LN-742 voltmeter does not function or read correctly when the actual arc voltage is present. The wire feeder is feeding wire correctly. 1. Make sure the polarity switch on the Lincoln welding power source is in the correct position for the welding process. RECOMMENDED COURSE OF ACTION 2. Check or replace the control cable.
E-5 E-5 TROUBLESHOOTING Observe all Safety Guidelines detailed throughout this manual PROBLEMS (SYMPTOMS) POSSIBLE AREAS OF MISADJUSTMENTS(S) The purge key does not activate the gas solenoid. The solenoid does activate when the gun trigger is pulled. 1. Contact your local Lincoln Authorized Field Service Facility. The gas solenoid does not activate either when the purge key is pressed or when the gun trigger is pulled. 1. Check plug J6, located on the control board for loose or faulty connections.
E-6 E-6 TROUBLESHOOTING Observe all Safety Guidelines detailed throughout this manual PROBLEMS (SYMPTOMS) POSSIBLE AREAS OF MISADJUSTMENTS(S) The wire is feeding rough or not feeding. The drive rolls are turning. 1. Check for mechanical restrictions in the wire feeding path. Check the gun and gun components. RECOMMENDED COURSE OF ACTION 2. Check the drive roll position and idle roll pressure. 3. The electrode may be dirty or rusty. The drive rolls do not turn when the gun trigger is pressed.
E-7 E-7 TROUBLESHOOTING Observe all Safety Guidelines detailed throughout this manual PROBLEMS (SYMPTOMS) POSSIBLE AREAS OF MISADJUSTMENTS(S) The welding arc is variable or “hunting”. 1. Check the welding cables for loose or faulty connections. RECOMMENDED COURSE OF ACTION 2. Make sure the wire feed speed, voltage, polarity and shielding gas are correct for the process being used. 3. Check for mechanical restrictions in the wire feed path. Poor arc striking with sticking or “blast-offs”.
AC + - LN-742 & LN-742H L CAVITY NUMBERING SEQUENCE R.F.
NOTES LN-742 & LN-742H
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NOTES LN-742 & LN-742H
NOTES LN-742 & LN-742H
● Do not touch electrically live parts or WARNING Spanish AVISO DE PRECAUCION French ATTENTION German WARNUNG Portuguese ATENÇÃO ● Keep flammable materials away. ● Wear eye, ear and body protection. ● Mantenga el material combustible ● Protéjase los ojos, los oídos y el 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 mojada. ● Aislese del trabajo y de la tierra.
● Keep your head out of fumes. ● Use ventilation or exhaust to ● Turn power off before servicing. ● Do not operate with panel open or guards off. remove fumes from breathing zone. ● Los humos fuera de la zona de res- piración. ● Mantenga la cabeza fuera de los humos. Utilice ventilación o aspiración para gases. ● Gardez la tête à l’écart des fumées. ● Utilisez un ventilateur ou un aspira- ● Desconectar el cable de ali- mentación de poder de la máquina antes de iniciar cualquier servicio.
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