Vaisala AWS330 User Manual
Page 244
User's Guide ______________________________________________________________________
242 _________________________________________________________________ M211296EN-B
Table 74
Jumper Settings for DSI486-B
Jumper Connected
Pins
Function
1-2
Channel B RS-232 mode
X3
2-3
Channel B RS-485 mode (default)
1-2
Channel B RS-485 mode (default)
X6
2-3
Channel B RS-232 mode
X4
1-2
Channel A RS-485 line terminating resistor
active
X5
1-2
Channel B RS-485 line terming resistor active.
Do not use in RS-232 mode
The dual RS-485 module also provides an SDI-12 connection. The SDI-
12 line uses one wire for data and is limited to the maximum length of
60 meters. Figure 130 below provides a schematic wiring diagram for the
SDI-12 connection and the 12 VDC power supply for a sensor. The
jumper settings should be as shown in Figure 128 on page 241.
1006-103
Figure 130 Dual RS-485 Wiring Diagram for SDI-12 and 12 VDC
Power Supply
Simultaneously with the SDI-12, you can connect channels A and B in
the 2-wire RS-485 mode.