Theory of operation, Input line voltage, General description – Lincoln Electric INVERTEC V250-S User Manual
Page 26
E-2
THEORY OF OPERATION
E-2
INPUT LINE VOLTAGE
The single-phase or three-phase input power of 208,
230 or 460 volts AC is connected to the machine,
through a line switch located on the front panel.
A reconnect panel and switch allows the user to con-
figure the machine for either a low or high input volt-
age and also connect the auxiliary transformer for the
appropriate input voltage.
The auxiliary transformer develops the appropriate AC
voltages to operate the cooling fans and the control
board.
FIGURE E.1 - INPUT VOLTAGE CIRCUITS
INVERTEC V250-S
INPUT
LINE
SWITCH
INPUT
RECTIFIER
R
E
C
O
N
N
E
C
T
S
W
I
T
C
H
AUXILIARY
TRANSFORMER
FAN
MOTORS
POWER BOARD
MAIN
TRANSFORMER
SHUNT
POSITIVE
OUTPUT
TERMINAL
NEGATIVE
OUTPUT
TERMINAL
THERMAL
LIGHT
REMOTE
RECEPTACLE
OUTPUT
CONTROL
STRIKE
CONTROL
ARC
FORCE
CONTROL
MODE
SWITCH
LOCAL/
REMOTE
SWITCH
RELAY
CAPACITOR
CAPACITOR
IGBT
IGBT
IGBT
IGBT
CURRENT
TRANSFORMER
18VAC
GATE SIGNALS
THERMOSTATS
O
V
E
R
V
O
L
T
A
G
E
PROTECTION SIGNAL
CR1 RELAY DRIVE SIGNAL
CR1
IGBT
CONTROL BOARD
A"
L
E
A
D
"
F
E
E
D
B
A
C
K
F
E
E
D
B
A
C
K
NOTE: Unshaded areas of block logic diagrams are the subject of discussion.
GENERAL DESCRIPTION
The Invertec V250-S is a 250 amp arc welding power source that utilizes either single or three phase input power
to produce a constant current output. The output response of this machine has been optimized for the SMAW
and TIG welding processes.