Dendrometer Data Logger DL18 BLE
5
4) Raw Data conversion & Linear scaling
Fig. 7: Linear scaling function
On-logger linear data conversion:
If configured as
“Adapter Cable, Cable-2.5-Stereo (0-2.5 Volts DC)”, the raw measured
data is in units of volts, ranging between 0 and 2.5 VDC. In case of a linear relationship
between raw sensor output voltage and the parameter measured by the sensor, the linear
scaling function can be configured to convert raw voltage signals directly on the logger
(see Fig. 7). This is possible for all dendrometers except for the models DC3 and DC4, the
air temperature and humidity sensor (T/RH-Sens), soil moisture sensor (EM 35), and light
sensors (PAR: EM 20, Pyranometer: EM 25). The on-Logger linear scaling is configured
via two value pairs (e.g. 0 VDC / X and 2.5 VDC / Y). The parameters X and Y are sensor
dependent and in case of dendrometers X is always 0 (i.e. 0 VDC corresponds to 0 mi-
crometer), whereas Y differs depending on the dendrometer model the different Y factors
are.
Fig. 8 Enter linearization data
For example for 11000 micrometer range sensors (e.g. DD-S2, DR3, DD-L1,
…) the cor-
rect configuration is: 0 VDC / 0 micrometers and 2.5 VDC / 11000 micrometers.
Change the value in this field as follows. Other 3 data fields remain unchanged.
11,000.0000 for DR1, DR3, DD-L1, DD-S1, DD-S2, DRO, DRW, DDW, DC1, DV, DF1
25,400.0000 for DC3, DD-L2, DR2, DF2
50,800.0000 for DC4, DD-L3, DF3
150,000.0000 for DF4