Main
LF-72/74
SVM171-A
SERVICE MANUAL
Safety Depends on You
FOR ENGINE powered equipment.
WARNING
ELECTRIC AND MAGNETIC FIELDS may be dangerous
ARC RAYS can burn.
ii
FUMES AND GASES can be dangerous.
AUG 06
ii
FOR ELECTRICALLY powered equipment.
iii
CYLINDER may explode if damaged.
Mar 95
WELDING SPARKS can cause fire or explosion.
PRCAUTIONS DE SRET
iv
PRCAUTIONS DE SRET POUR LES MACHINES SOUDER TRANSFORMATEUR ET REDRESSEUR
Mar. 93
iv
MASTER TABLE OF CONTENTS FOR ALL SECTIONS
vv
LF-72/74 SINGLE/DUAL
-INSTALLATION SECTION -
TECHNICAL SPECIFICATIONS
:
LF-72 Wire Feeder
LOCATION
ELECTRIC SHOCK can kill.
MOUNTING
Page
WELD CABLE SIZES
COAXIAL WELD CABLES
WELD CABLE CONNECTION
Electrode Work
Work
ANALOG CONTROL CABLE
CONTROL CABLE CONNECTIONS
POWER SOURCE WIRE FEEDER
NOTES
ANALOG MILLER CONTROL CABLE ADAPTER K2335-1
MILLER POWER SOURCE
LINCOLN WIRE FEEDER
WELDING GUN/WIRE FEEDER TRIGGER CONNECTOR
WIRE DRIVE SYSTEMS
WELDING GUNS, TORCHES AND ACCES- SORIES
WIRE DRIVE CONFIGURATION
PROCEDURE FOR CHANGING DRIVE AND IDLE ROLL SETS
WARNING WARNING
PRESSURE ARM ADJUSTMENT
WIRE REEL LOADING
WELD WIRE ROUTING
SHIELDING GAS CONNECTION
INSTALLING ELECTRODE CONDUIT KITS
"O" RING
ALUMINUM WIRE PREPARATIONS
Page
TYPICAL SYSTEM CONFIGURATIONS
Page
-OPERATION SECTION -
SAFETY PRECAUTIONS
COMMON WELDING ABBREVIATIONS
PRODUCT DESCRIPTION
RECOMMENDED PROCESSES
REQUIRED EQUIPMENT
FRONT PANEL CONTROLS AND CONNECTIONS
1. REMOTE VOLTAGE CONTROLKIT
2. BURNBACK AND POSTFLOW TIMER KIT
5.
3. THERMAL LED, MOTOR OVERLOAD
4. COLD FEED/GAS PURGE SWITCH
6. WIRE FEED SPEED KNOB
7. GUN RECEIVER BUSHING (K1500-2)
8.
TRIGGER CONNECTOR 5-PIN AMPHENOL
Page
Page
Page
Page
Page
Page
Page
MAINTENANCE
Safety Precautions
ROUTINE MAINTENANCE
PERIODIC MAINTENANCE
CALIBRATION SPECIFICATION
FIGURE D.1
FIGURE D.2
Page
-INSTALLATION SECTION -
TECHNICAL SPECIFICATIONS
:
LF-74 Wire Feeder
LOCATION
ELECTRIC SHOCK can kill.
MOUNTING
Page
WELD CABLE SIZES
COAXIAL WELD CABLES
WELD CABLE CONNECTION
Electrode Work
Work
ANALOG CONTROL CABLE
CONTROL CABLE CONNECTIONS
ANALOG MILLER CONTROL CABLE ADAPTER K2335-1
MILLER POWER SOURCE
LINCOLN WIRE FEEDER
WELDING GUN/WIRE FEEDER TRIGGER CONNECTOR
HIGH FREQUENCY PROTECTION
WIRE DRIVE SYSTEMS
Trigger Lead
WELDING GUNS, TORCHES AND ACCES- SORIES
WIRE DRIVE CONFIGURATION
ASSEMBLY OF DRIVE ROLLS AND WIRE GUIDES
PRESSURE ARM ADJUSTMENT
SHIELDING GAS CONNECTION
WIRE REEL LOADING
WELD WIRE ROUTING
INSTALLING ELECTRODE CONDUIT KITS
ALUMINUM WIRE PREPARATIONS
Page
COMMON EQUIPMENT SET-UPS
FIGURE AA.15 HIGH VOLUME PRODUCTION
FIGURE AA.16 PORTABLE WELDING
8
7A
10
7
9 5C
-OPERATION SECTION -
SAFETY PRECAUTIONS
RECOMMENDED PROCESSES
REQUIRED EQUIPMENT
PRODUCT DESCRIPTION
FRONT PANEL CONTROLS AND CONNECTIONS
1. WIRE FEED SPEED KNOB
2. REMOTE VOLTAGE CONTROLKIT
3. BURNBACK AND POSTFLOW TIMER KIT
4. THERMAL LED, MOTOR OVERLOAD
5. COLD FEED/GAS PURGE SWITCH
6.
2STEP - TRIGGER INTERLOCK SWITCH
8.
7. GUN RECEIVER BUSHING (K1500-2)
TRIGGER CONNECTOR 5-PIN AMPHENOL
Page
Page
Page
LF-72/74
Page
Page
Page
MAINTENANCE
Safety Precautions
ROUTINE MAINTENANCE
PERIODIC MAINTENANCE
CALIBRATION SPECIFICATION
Page
Page
-THEORY OF OPERATION SECTION -
FIGURE E.1 LF-72/74 BLOCK LOGIC DIAGRAM
CONTROL BOARD
CONTROL BOARD
THEORY OF OPERATION
GENERAL DESCRIPTION
INPUT RECEPTACLE, CONTROL BOARD AND OPERATOR CON- TROLS
THEORY OF OPERATION
DRIVE MOTOR, TACH FEEDBACK AND GAS SOLENOID
CONTROL BOARD
Page
-TROUBLESHOOTING & REPAIR SECTION -
HOW TO USE TROUBLESHOOTING GUIDE
PC BOARD TROUBLESHOOTING PROCEDURES
PROBLEMS (SYMPTOMS)
POSSIBLE AREAS OF MISADJUSTMENT(S)
RECOMMENDED COURSE OF ACTION FUNCTION PROBLEMS
PROBLEMS (SYMPTOMS)
POSSIBLE AREAS OF MISADJUSTMENT(S)
RECOMMENDED COURSE OF ACTION FUNCTION PROBLEMS (Continued)
Page
DRIVE MOTOR AND TACH FEEDBACK TEST
TEST PROCEDURE
MOTOR AND TACH FEEDBACK TEST (continued)
GAS SOLENOID TEST
GAS SOLENOID
GAS SOLENOID TEST (continued)
DIODE BRIDGE TEST
DIODE BRIDGE TEST (continued)
WIRE SPEED POTENTIOMETER TEST
WIRE SPEED POTENTIOMETER TEST (Continued)
Figure F.5
PC BOARD REMOVAL AND REPLACEMENT
REMOVAL PROCEDURE
REPLACEMENT PROCEDURE
CONTROL BOARD
CONTROL PC BOARD REMOVAL AND REPLACEMENT PROCEDURE (Continued)
Figure F.6 - PC Board Location
WIRE DRIVE MOTOR AND GEAR BOX REMOVAL AND REPLACEMENT PROCEDURE
Figure F.7 - Wire Drive Motor(s)
PROCEDURE
Page
REPLACEMENT PROCEDURES
Page
Page
-ELECTRICAL DIAGRAMS SECTION -
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 11075, 11076, 11077 (L12146) LF-72
J6
P8
P5
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 11209, 11210, 11211,11227 (L12146-1) LF-72
J6
P8
P5
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 11290, 11291, 11292,11293 (L12146-2) LF-72
N.E.
N.D.
N.A.
ELECTRICAL DIAGRAMS
WIRING DIAGRAM - ENTIRE MACHINE - CODE 11195, 11196, 11197, (L12484) LF-74
N.E.
L6
P4
ELECTRICAL DIAGRAMS
SCHEMATIC - ENTIRE MACHINE - CODE 11075, 11076, 11077 (G4617) LF-72
is 1.5 ohms
P5
J4
ELECTRICAL DIAGRAMS
SCHEMATIC - ENTIRE MACHINE - CODE 11209, 11210, 11211,11227 (G4617-1) LF-72
is 1.5 ohms
P5
J4
ELECTRICAL DIAGRAMS
SCHEMATIC - ENTIRE MACHINE - CODE 11290, 11291, 11292,11293 (G4617-2) LF-72
on sheetpanel
y
r
ELECTRICAL DIAGRAMS
SCHEMATIC - ENTIRE MACHINE - CODE 11195, 11196, 11197, (G4942) LF-74
SheetPanel
CaseBack
L6