USER'S GUIDE____________________________________________________________________
28 __________________________________________________________________ M211371EN-B
Wiring
Standard Wiring
Connect supply voltage and RS-485 to port II. Port I does not need to
be used at all, and can remain covered.
15 ... 28 VDC
RS-485 +
RS-485 -
GND
+
SHIELD
-
1
2
3
4
2
4
1
3
1108-015
Figure 7
Wiring Non-Isolated RS-485
Wire Colors for Vaisala Cables
Pin
Connection on Port I Connection on Port II Wire Color
1
VDC
VDC
Brown
2
RS-485
D0-
White
3 GND
GND
Blue
4
RS-485
D1+
Black
Note the following:
- The ground pin (pin 3) on both ports is internally connected to
each other and to transmitter chassis. The chassis connection is
through a 1 M
Ω
resistor and a 40 nF capacitor that are connected
in parallel.
- The frames of the M8 connectors are not connected to the chassis.