Lincoln Electric 655/R - page 33

TABLE OF CONTENTS - THEORY OF OPERATION
E-1 E-1
Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC
POWER WAVE 655/R
Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-1
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-2
Input Voltage and Precharge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-3
Switch Boards and Main Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-4
DC Bus Board, Power Board, Feed Head Board, Gateway Board
and Voltage Sense Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-5
Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-7
Output Rectifier, and Output Choke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-8
Thermal Protection, Protective Circuits, Over Current Protection
and Under/Over Voltage Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-9
Insulated Gate Bipolar Transistor (IGBT) Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-10
Pulse Width Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .E-11
FIGURE E.1 — BLOCK LOGIC DIAGRAM.
+
INPUT
BOARD
LEFT
SWITCH
BOARD
RIGHT
SWITCH
BOARD
INPUT
RECTIFIER
CR1
GATEWAY
BOARD
DC
BUS
BOARD
FEED
HEAD
BOARD
POWER
BOARD
CONTROL
BOARD
OUTPUT
CHOKE
ELECTRODE
TERMINAL
THERMOSTATS
T1
T2
AUX
RECONNECT
RELAY
WATER
COOLER
115VAC
RECP.
115VAC
FAN
ARC LINK
WIRE
FEEDER
RECP.
S1
S6 CONNECTION
TOWIRE
DRIVE
S1
S6
VOLT
SENSE
BOARD
MAIN
TRANSFORMER
S5
CONTACTOR AND PRECHARGE
CONTROL SIGNALS FROM
CONTROL BOARD
FROM CONTROL
BOARD
2
4
V
A
C
115VAC
52VAC
230VAC
40VDC
40VDC
40VDC
40VDC
ARC LINK CONNECTION
TO
ROBOT
VOLTAGE SENSE
OUTPUT
CAP.V/F
FEEDBACK
CAP.V/F
FEEDBACK
IGBT DRIVE
FROM
CONTROL
BOARD
CT CURRENT
TO CONTROL
BOARD
-15V
+15V
+5V
+5V ARC LINK
+5V RS232
+15V SPI
STATUS THERMAL
LIGHT LIGHT
S2WORK
SENSE
LEFT S.B.
CAP.V/F
RIGHT S.B.
CAP.V/F
S3
RS232
LEFT CT
CURRENT
FB
C
U
R
R
E
N
T
F
B
ARC LINK
IGBT
DRIVES
TO
LEFT
S.B.
TO
RIGHT
S.B.
67A
67B
SW1
BUS BOARD
RECTIFIER
CURRENT
TRANSDUCER
OUTPUT DIODES
D1 -D4
115VAC
40VDC
DEVICE NET
VOLTAGE SENSE SELECT
IGBT DRIVE
FROM
CONTROL
BOARD
+5V SPI
RIGHT CT
CURRENT
FB
TO FAN RELAY
CONTACTOR AND
PRECHARGE
CONTROL SIGNALS
65VDC
WORK
TERMINAL
POWER WAVE 655/R
380-
415
440-
460
550-
575
+
ETHERNET/
A
A
HARMONIC
FILTER
C
POS
NEG
Auxiliary
Fan