Lincoln LN-742 English or Metric Speed Display Units, Circuit Protection, Acceleration Setting

Page 17

B-3

OPERATION

B-3

 

 

 

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. The bottom light indicates the weld feed speed (WFS) is being displayed.

INCREASE ARROW. This key increases the setting of the parameter selected to be displayed, using the “Quick-Set” feature for fast and accurate setting.

DECREASE ARROW. This key decreases the setting of the parameter selected to be displayed, using the “Quick-Set” feature for fast and accurate setting.

QUICK-SET FEATURE. This feature permits the arrow keys to control each display digit one at a time. The display digits blink in sequence from left to right. Pressing an arrow key immediately after a digit blinks alters that digit. Releasing the arrow key causes the left-to-right sequencing to resume.

COLD INCH KEY. This key energizes the wire feeder to inch the wire forward, but does not energize the power source or solenoid valve.

GAS PURGE KEY. This key energizes the solenoid valve to purge any remaining gasses, but does not energize the wire feeder or power source.

ENGLISH OR METRIC SPEED DISPLAY UNITS

Pressing both the Gas Purge key and Timer Selection key causes the speed display units to toggle between inches per minute (no decimal point displayed) or meters per minute (decimal point displayed). If the LED display is showing the voltmeter or one of the timer settings when these keys are pressed, the display will change to the weld speed to indicate the selected speed display units. See Figure B.1 for key locations.

CIRCUIT PROTECTION

The LN-742 has solid-state overload protection of the wire drive motor. If the wire drive motor becomes overloaded for an extended period of time, the protection circuitry turns off the power source, wire feeder, and solenoid, then displays the error code E30 on the LED display. This indicates the wire drive motor is overloaded, with the number indicating the time remaining in seconds before the unit will automatically reset. This number continues to decrement every second until it reaches zero. At that time the unit resets automatically and the previous display will return indicating that the unit is ready for operation.

Over loads can result from: improper tip size, liner, drive rolls, or guide tubes; obstructions or bends in the gun cable; feeding wire that is larger than the rated capacity of the feeder; or any other factors that would impede normal wire feeding.

ACCELERATION SETTING

Pressing both the Gas Purge key and the Function Selection key at the same time, on the keypad shown in Figure B.1, enables the acceleration setting display. The LED display will indicate “A-X” with “X” being a number from 1 (slowest) to 5 (fastest). This number is adjusted using the setting adjustment arrow keys. To exit the acceleration setting function, press both keys a second time, or press any other key except for the setting adjustment arrow keys.

DRIVE ROLL INSTALLATION

CHANGING DRIVE ROLLS FOR TWO- ROLL WIRE FEEDERS:

To change drive rolls on a two-roll wire feeder, refer to Figure B.2 and perform the following steps:

1.Turn off the welding power source.

2.Rotate the latch knob on the quick release arm.

LN-742 & LN-742H

Page 16 Page 18
Image 17
Page 16 Page 18
Contents LN-742 & LN-742H Wire Feeders California Proposition 65 Warnings SafetyElectric Shock can kill Cylinder may explode if damaged Sûreté Pour Soudage a L’Arc Précautions DE SûretéThank You Table of Contents Technical Specifications LN-742 InstallationInput Cable Connections Mounting LocationFigure A.2 Strain Relief Clamp PIN Work Cable Table A.1 Work Lead SpecificationsGUN and Cable Assemblies GUN Cable ConnectionsFigure A.5 Water Connections Water Connections For Water Cooled GunsFigure A.6 Shielding GAS Hookup Gmaw Shielding GAS HookupOperation Safety PrecautionsOperating Instructions General DescriptionFigure B.1 Wire Feeder Controls Controls and SettingsDrive Roll Installation Acceleration SettingChanging Drive Rolls for TWO- Roll Wire Feeders English or Metric Speed Display UnitsGuide Tube Detail Changing Drive Rolls for FOUR- Roll Wire Feeders Figure B.3 Installing Drive Rolls on a FOUR-ROLL Feeder Figure B.4 Idle Roll Pressure Setting Idle Roll Pressure SettingFigure B.5a Threaded Locking Collar Wire LoadingInnershield Coils Electrode Feeding and Brake AdjustmentTo Mount a 50 or 60 LB Coil Adjustable Wire Reel BrakeFigure B.7 K1504-1 Coil Reel READI-REELS a K438 READI-REEL Adapter Must be UsedMaking a Weld Wire Reel ChangingGeneral AccessoriesTable C.1 LN-742 Accessories K163 Undercarriage K589-1 Remote Control KITK178-1 Mounting Platform Solenoid KITWelding Guns Power Input CablesSPINDLES, STANDS, Adapters Attaching the Wire Reel Stand Table C.2 Drive Roll KIT Numbers Drive Roll KitsPeriodic Maintenance MaintenanceRoutine Maintenance HOW to USE Troubleshooting Guide TroubleshootingTroubleshooting Troubleshooting Troubleshooting Troubleshooting Troubleshooting Troubleshooting Diagrams LN-742 & LN-742H LN-742 & LN-742H LN-742 & LN-742H LN-742 & LN-742H Precaucion Warnung

LN-742, LN-742H specifications

The Lincoln LN-742H and LN-742 are renowned models in the realm of industrial welding equipment, specifically designed to cater to the needs of professional welders and fabricators. These machines stand out for their robustness, advanced technology, and ease of use, making them popular choices in various industries, including construction, automotive, and manufacturing.

One of the main features of the Lincoln LN-742H and LN-742 is their powerful Arc control capabilities. The machines are equipped with innovative technology that allows for consistent arc stability, which is crucial for achieving high-quality welds. The adjustable arc force enables users to tailor the welding parameters to their specific applications, facilitating optimal penetration and minimal spatter.

The LN-742H model is particularly notable for its enhanced portable design, making it easier for operators to transport the machine to different job sites. This portability does not compromise its power, as it offers a high output suitable for both thin and thicker materials. Moreover, the LN-742 model comes with a highly efficient cooling system that ensures the machine runs smoothly without overheating, even during prolonged use.

Both models feature an intuitive user interface that simplifies the welding process. The digital display offers real-time feedback on the welding parameters, allowing welders to make precise adjustments as needed. This feature is especially beneficial for beginners, who may be unfamiliar with optimal welding settings.

Another impressive characteristic of the Lincoln LN-742H and LN-742 machines is their versatility. They support various welding processes, including MIG, TIG, and stick welding, giving users the flexibility to choose the most suitable method for their projects. This adaptability makes these models an ideal solution for shops that handle a wide range of welding tasks.

Durability is a significant consideration in the design of the LN-742H and LN-742, as they are built with high-quality materials that withstand heavy use and challenging conditions. The rugged construction extends the lifespan of the machines, reducing the need for frequent repairs and servicing.

In summary, the Lincoln LN-742H and LN-742 welding machines exemplify advanced engineering and user-focused design. Their combination of powerful performance, portability, user-friendly features, and versatile applications makes them essential tools for professionals in the welding industry, paving the way for excellence in metal fabrication and repair.
Top Page Image Contents