AO2000 CONTINUOUS GAS ANALYZERS  |  OI/AO2000-EN REV. B  109
 
 
 
Modbus module: Electrical connections 
 
RS232 interface 
Pin Signal 
2 RxD 
3 TxD 
5 GND 
Design: 9-pole male Sub-D plug 
RS485 interface 
Pin Signal 
2 RTxD– 
3 RTxD+ 
5 GND 
Design: 9-pole female Sub-D plug 
NOTE 
For additional information on "Modbus", refer to the Technical Information 
"AO2000 Modbus and AO-MDDE".