User manual
Table Of Contents
- 1 FOREWORD
- 2 INTRODUCTION
- 3 PRINCIPLE OF OPERATION
- OPTIONS AND SPECIFICATION
- INSTALLATION REQUIREMENTS
- INSTALLATION
- 7 MECHANICAL
- 8 OUTPUT FORMATS
- 9 ANALOGUE OUTPUTS AND OPTIONS
- 10 METPAK SDI-12
- 11 MAINTENANCE & FAULT-FINDING
- 12 TESTS
- 13 APPENDICES
- CS215_jun06.pdf
CS215 Temperature and Relative Humidity Probe
The aR! Command would therefore be preferable in fast running programs as it
takes less time to execute.
The aC! concurrent measurement command can also be used where the sensor
measurement is initiated with one command and data is collected after a minimum
delay of one second or any time thereafter. With Campbell Scientific dataloggers
this is done by using the SDI-12 recorder instruction with the aC! command. The
datalogger will return -99999 or NaN (for CRBasic loggers) for the temperature
reading for the call of the instruction that initiates the measurement. At the next
call of the instruction the datalogger will request the data and record the correct
temperature.
5.2.2 CRBasic Dataloggers
CRBasic dataloggers that support the Slowsequence function (the CR1000 and
CR5000) can run the SDI-12 instruction entirely as a background process causing
minimum interference to other measurements that use the analogue hardware.
This is implemented by including the measurement in a Slowsequence section of
the program, thus allowing faster programs to run as the main scan.
NOTE: For the CR5000 use a control port rather than the SDI-12
port to allow the SDI12recorder instruction to run in the slow
sequence.
The example program below shows how the Slowsequence can be used to make
measurements from the CS215 whilst the main scan can run at a much faster rate.
'CR5000 Series Datalogger
'Example program showing measurement of a single CS215 sensor every 30 sec
'in the slow sequence
'Declare the variables we are going to use
Public Batt_Volt, PTemp, CS215meas(2) 'An array suitable to reading the SDI12 data
into
Alias CS215meas(1) = Temperature
Alias CS215meas(2) = RH
'Main Program - in this example it is running fast just measuring the
'battery voltage and panel temperature
BeginProg
Scan (50,mSec,0,0) 'Scan every 50 milliseconds
PanelTemp (PTemp,250)
Battery (Batt_volt)
NextScan
SlowSequence
'Define Data Table to hold the stored data for the CS215
DataTable (CS215dat,1,-1)
DataInterval (0,15,min,1) 'As an example store the average every 15 mins
Average (1,Temperature,IEEE4,False)
Average (1,RH,IEEE4,False)
EndTable
Scan (30,sec,0,0)
SDI12Recorder (CS215meas(),1,0M!,1.0,0) 'Read the values into the array
'NOTE: we had to use a control port for SDI-12 as this is in the slow sequence
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