ALM-BR4-4.3 Manual
7
Copyrights ECOTRONS LLC www.ecotrons.com
Connector Pin #
Name
Description
Min Max
Connector
A
1
RH
Wideband oxygen sensor input
—
—
2
UN
—
—
3
IA
—
—
4
IP
—
—
5
VM
—
—
6
VS
—
—
Connector
B
1
GND-H Ground (Heater circuit ground)
0V
0V
2
+12V
+12V Power supply
9V
15V
3
GND-R
Ground (Reference ground)
0V
0V
Connector
C
A
RS-485 Communication
B
RS-485 Communication
GND
Ground (Reference ground)
0V
0V
5.2 Communication Protocol for RS485 Bus
RS485 communication is based on Modbus protocol. Ecotrons Modbus protocol uses
ASCII and RTU mode and supports PLC, DTC, etc.
More details refer to ALM Communication Protocol
– SCI.doc
http://www.ecotrons.com/download/
RTU mode:
Upload O
2
%, Lambda, and LSU Temperature
PLC
→
ALM, PLC sends: "50 03 2000 0004 42 48"
ALM
→
PLC, PLC receives: "50 03 08 xxxx xxxx xxxx xxxx xxxx"
