THEORY OF OPERATION
E-7 E-7
POWER WAVE 655/R
Return to Section TOC Return to Section TOC Return to Section TOC Return to Section TOC
Return to Master TOC Return to Master TOC Return to Master TOC Return to Master TOC
NOTE: Unshaded areas of Block Logic
Diagram are the subject of discussion
CONTROL BOARD
The Control Board performs the primary interfacing
functions to establish and maintain output control of the
Power Wave 655R machine. The function generator
and weld files exist within the Control Board hardware
and software. Digital command signals and arc voltage
and current feedback information is received and
processed by software located on the Control Board.
The appropriate pulse width modulation (PWM) signals
are then sent to the gates of the Switch Board IGBTs to
create the high-speed, digitally controlled welding
waveform. (See PULSE WIDTH MODULATION dis-
cussion in this section).
In addition, the Control Board monitors the ther-
mostats, the main transformer primary currents and
input filter capacitor voltages. Depending on the fault
condition, the Control Board will activate the thermal
and/or the status light and will either disable or reduce
the machine output. In some conditions the input con-
tactor will be de-energized.
FIGURE E.6 – CONTROL BOARD
+
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