Vaisala Hydromet Data Collection Platform - Manual (Page 30)

User's Guide ______________________________________________________________________
28 ___________________________________________________________________M210784EN-E
Communication Modules
RS-232 Module
The RS-232 communication module is unisolated, providing either a
double serial channel without handshaking (dual RS-232 module) or a
single RS-232 with handshaking (single RS-232 module). The power
consumption is less than 15 mA when communicating, less than 5 mA
at standby.
The later version of the module (DSU232C) adds a separate SDI-12
interface that can be taken into use by jumper selection. Wiring for the
SDI-12 is similar to the dual RS-485 module described in section
Dual-
Isolated RS-485 Communication Module on page 29 .
In other aspects, the later version is compatible with the old one and can
thus be used as a spare part without modifications to the system.
0403-106 Figure 8 RS-232 Communication Module DSU232
Isolated RS-485 Communication Module
0403-107 Figure 9 Isolated RS-485 Communication Module DSI485