Campbell Scientific CS650 and CS655 Water Content Reflectometers - Manual (Page 27)

CS650 and CS655 Water Content Reflectometers
The proper sequence in the datalogger program for measuring CS650 probes
on a multiplexer is:
1. Set RES control port high to enable multiplexer
2. Pulse CLK control port to advance to next multiplexer channel
3. Set switched 12 volt channel high to supply power to CS650
4. Send SDI-12 command(s) to CS650
5. Set switched 12 volt channel low to remove power from CS650
6. Repeat steps 2 – 5 for each CS650 connected to the multiplexer
7. Set RES control port low to disable multiplexer
Program examples in Section 6.6, Program Examples, show the commands
used in CRBasic and Edlog for this sequence.
6.6 Program Examples
6.6.1 CR1000 With a Single CS650 Probe
This CRBasic example program measures one CS650 probe on a CR1000
every 15 minutes, storing hourly averages of volumetric water content,
electrical conductivity, and soil temperature and samples of permittivity, period
average and voltage ratio. The CS650 has a SDI-12 address of 0. Wiring for
the example is shown in TABLE 6-5.
TABLE 6-5. Wiring For Program Example 1
CR1000 CS650
12V Red
C1 Green
G Black, Orange, Clear
Code Example 1. CRBASIC Code: CR1000 Program to Measure a Single
CS650 Probe
Public CS650(6)
'Assign aliases to the public array
Alias CS650(1)=VWC: Alias CS650(2)=EC: Alias CS650(3)=TSoil
Alias CS650(4)=Perm: Alias CS650(5)=PerAvg: Alias CS650(6)=VoltR
Units VWC = m^3/m^3: Units EC = dS/m: Units TSoil = deg C
DataTable (DatoutCS650,1,-1)
DataInterval (0,60,Min,2)
Average (3,CS650(1),FP2,False)
Sample(3,CS650(4),IEEE4)
EndTable
BeginProg
Scan (15,Min,0,0)
SDI12Recorder (CS650(1),1,0,"M3!",1.0,0)
CallTable DatoutCS650 'Call Data Table
NextScan
EndProg
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