HD2013
- 10 -
V1.6
Connection of the optional CPM12AA4.x cable to the rain gauges with analog
or SDI-12 output option:
Connector pin
Function
Wire color
1
Power supply positive (+Vdc)
Red
2
GND
Blue
3
Analog or SDI-12 output positive (OUT)
White
4
Cable shield
Black
The cable shield (black wire) can be left disconnected inside the rain gauge (isolate or
cut the wire terminal to avoid unwanted contacts).
3.2
C
ONFIGURATION OF ANALOG OUTPUT
The analog output is proportional to the partial amount of rainfall (amount of rainfall
from the last reset command). The analog output full scale (20 mA or 10 V) can be as-
sociated with different values of rainfall. The association can be implemented via hardware,
by using the
dip switches
on the circuit board, or via software, by connecting the serial
communication port
COM PC
of the rain gauge to the PC.
The dip switches allow setting three rainfall values: 25, 100 or 250 mm (1, 5 or 10
inches if the set unit of measurement is “inches”), as shown in figure 3.4.
If both the dip switches are set to ON, the rainfall value considered is the one set via
serial port with the command
CRW
(see the table of the serial commands).
Fig. 3.4 – Dip switches
Warning: after reaching the full scale value, the measurement is reset and
the analog output returns to the initial scale value.
COM PC serial port
Connector
reference
Female connector
outside view
