Section e - theory of operation – Lincoln Electric POWER MIG SVM157-A User Manual
Page 29

TABLE OF CONTENTS
- THEORY OF OPERATION SECTION -
POWER MIG 200
Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Section E
Input Power Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Input Line Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Voltage Selector Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Baffle Mounted Diode Bridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Output Rectification, Contactor & Control Boards . . . . . . . . . . . . . .
Control Board, Gun Trigger, & Wire Drive Motor . . . . . . . . . . . . . . .
Protective Devices & Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermal Overload Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wirefeed Overload Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Section E
Section E
FIGURE E.1 THEORY OF OPERATION BLOCK DIAGRAM
LINE
SWITCH
RECONNECT
PANEL
FAN
MOTOR
RECTIFIER
DIODE
BRIDGE
CONTROL BOARD
GAS
SOLENOID
WIRE
SPEED
CONTROL
WIRE
DRIVE
MOTOR
TACH
FEEDBACK
GUN TRIGGER
+
-
OUTPUT DIODE
BRIDGE
+
-
NEGATIVE
TERMINAL
CONTACTOR
CONT
ACT
OR
CONTROL
TAP SELECTOR
SWITCH
OUTPUT
CHOKE
POSITIVE
TERMINAL
TRANSFORMER
THERMOSTAT
OUTPUT BRIDGE
THERMOSTAT
28 V
AC
MAIN
TRANSFORMER
OUTPUT
CAPACITORS
GUN
ASSEMBLY