Protection fitted to comply
to SDI-12 standard on the
serial port output  

Speaker Selection Switch

Speaker

Gas Discharge Tube
Lightening protection

User Display

Comms Port Pin-out

12  Earth
11  Earth
10  Earth
9  Earth
8                NPN-4
7                 NPN-3
6                NPN-2
5  NPN-1
4  RS-485 -
3  RS-485 +
2  +12V   
1  GND  

Frequency Hz

+
Sense
-
+
Therm
-

VW-108

Thermistor

Communications

Maximum Network Length   200 ft
Maxiumun number of VW108   10 per network string
Baud Rate    1200
Network Connection    2 wires only

Sensor Connection Diagram

The photograph below shows the VibWire108-SDI12
without its protective cover