Lambrecht Ser[LOG], Руководство оператора

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LAMBRECHT meteo GmbH Ser[LOG] Manual Page 59 of 129
5.3.5.5.5 Channel type - SDI-12
In Ser[LOG], the measured values of SDI-12 sensors are broken down into their measured value struc-
ture. Each measured value is defined as a separate "sensor".
The Ser[LOG] supports from the SDI-12 specification only the "CC" command to initialize the measure-
ment in the SDI-12 device. Subsequently, as many D0 to D9 commands are sent until all announced
measured values have been read in Ser[LOG].
For processing, a large data sequence is generated from all individual measured value sets, which is
accessed by the SDI-12 sensor definitions.
A distinction is made between data types in:
Single measurement value The measured value is stored individually as instantane-
ous value and transferred unchanged to a measurement
channel.
Measured value group AVR/SUM, MIN,
MAX
The sensor delivers the measured data as AVR=Aver-
age or SUM=Sum and as MIN=Minimum, MAX=Maxi-
mum
In the fields "Measured value position", "Minimum position" and "Maximum position" of the data type
"Measured value group AVR/SUM, MIN, MAX" the position of the respective value in the data sequence
is entered. For the data type "Single measurement", enter the same position in each of the 3 fields.
The "processing" of the measured value during transfer from the SDI-12 protocol can be carried out
according to the following rules:
Standard - Accept value only The measured value is taken over directly and fed to the
measured value processing.
Difference new value - old value The difference is calculated from the previous measured
value to the current measured value. Used, for example,
to calculate the amount of precipitation from the total
quantity since the device was started.
Percent from 0-1 is 0% to 100% Used, for example, for status information that is to be
processed in percent.
Examples of SDI-12 sensors
In this example, a single measured value
which is at the 4th position in the data se-
quence of the SDI-12 device is taken over and
transferred unchanged to a measured value
channel of the Ser[LOG].
This example shows how the measured val-
ues are taken from an SDI data set that pro-
vides average, minimum and maximum values
for a measured value for the period from data
retrieval to data retrieval.
5.3.5.5.6 Channel type - Serial (e. g. NMEA)
Several protocols for serial sensors are implemented in Ser[LOG]. Most serial sensors are already avail-
able as predefined sensors. To be able to access measured values retrieved with these protocols, a
sensor is defined for each measured value.