Sutron Corporation X-Link Operations & Maintenance Manual, Rev 1.63 5/24/2016 pg. 107
+ SIG
Diff C +
- SIG
Diff C -
This X-Link setup will measure solar radiation, in units of Watts per m², from the
sensor that has a sensitivity of 79.4uV / Wm² (.0000794 V/ Wm²).
Since the X-Link multiplies the voltage by the scale factor, we want to know how
many Wm² one volt equals. Also, we have tied the + side to the Vref to keep the
input within the range of the analog circuit, so we also need to apply a negative
slope (a positive change from the sensor will look like it is going negative to the
X-Link).
1 Volt / (0.0000794V / Wm²) * -1= -12594.46 Wm²
Therefore, for an instantaneous reading of solar irradiance, not an integrated
reading, where you want the reading in Watts per square meter and not kilo-
Watts per square meter, then you have a large slope. For kW/m-2 the slope
would be 12.59446
Solar Radiation
Setup
Value
Active
On
Label
SOLRAD
Meas Type
Analog
Analog Type
Diff C
Input Range
-312 to +312mV
Warmup
3 sec
Averaging Time
00:00:00
Slope
-12594.46
8.7.
SDI-12 Multi-Parameter Sensor
This section describes how to connect the sensor and how to set up X-Link to
measure several parameters from a single SDI-12 sensor.
The SDI-12 sensors use three wires for connection: one for data, one for power +
and one for power -. To wire it up, connect as follows:
SDI-12 Sensor
X-Link input
Data
Terminal Block 3
Power +
Terminal Block 4
Power -
Terminal Block 5
This X-Link setup measures several parameters from a single SDI-12 sensor. Note
how the address, command, measurement time and interval are all the same.
(This is what tells X-Link to only issue the measurement command once, then get
the three parameters from the one measurement):
