Laurel Electronics Modbus Protocol For Series 2 Laureate Digital Panel Meters, Counters, Timers & DIN-Rail Transmitters - Manual (Page 7)

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N/C
ISO GND
RX
TX
RTS
N/C
GND
TX
RX
RTS
RS232 INTERFACE Computer
6
5
4
3
2
1
ISO GND
BRX
ARX
ATX
BTX
ISO GND
GND
BTX
ATX
ARX
BRX
GND
RS485 INTERFACE - FULL DUPLEX
GND
ATX / ARX
BTX / BRX
GND
RS485 INTERFACE - HALF DUPLEX
1
2
3
4
5
6
7
8
(A') RXD0 -
(B') RXD1 +
(B) TXD1 *
(A) TXD0 -
ISO GND
TXD0
TXD1
RXD1
RXD0
GND
RS485-MODBUS - FULL DUPLEX RS485-MODBUS - HALF DUPLEX
(B) TX / RXD1
(A) TX / RXD0
ISO GND
(B) TX/RXD1
(A) TX/RXD0
GND
6
5
4
3
2
1
6
5
4
3
2
1
ISO GND
ATX / ARX
BTX / BRX
ISO GND
1
2
3
4
5
6
7
8
4. TRANSMITTER CONNECTOR WIRING
Signal
conditioner
board
P3 Solid
state relays
P1 Power
input
P6 Signal
input &
excitation
output
P2 Serial
data I/O P4 Analog
output
1
2
3
4
5
6
RS485 RS232
6 N/C TX
5 ARX RX
4 ATX NC
3 GND GND
2 BRX GND
1 BTX N/C
3 Power GND
2 AC neutral or -DC
1 AC high or +DC
See below
for different
signal types
Analog out - 1
Analog out + 2
AL2 1
AL2 2
AL1 3
AL1 4
5
4
3
2
1
9
8
7
6
RS232 cable with
rear view of
DB9
connector to PC