Campbell Scientific CS11-L Current Transformer - Manual (Page 19)

CS11-L Current Transformer
samples 25 times, and the second CR200X example program has a loop that
samples 30 times. A 25-sample loop produces almost two cycles of a 60 Hz
waveform, and a 30-sample loop produces almost two cycles of a 50 Hz
waveform (see FIGURE 6-1). The average energy under the curve is
calculated using the RMSSpa instruction. A multiplier of 0.2 is applied to the
rms value; see Appendix A.4, Multiplier, for more information.
25 Samples of Amperage on CR200X Datalogger (60 Hz)
or 30 Samples of Amperage on CR200X Datalogger (50 Hz)
25 samples of Amperage on CR200 datalogger
-80
-60
-40
-20
0
20
40
60
80
1 3 5 7 9 11 13 15 17 19 21 23 25
Instanteneous Amps
mV
CS11-L waveform
FIGURE 6-1. Graph of a CS11-L waveform
6.2.1 CR200(X) Program for 60 Hz
'CR200 Series Datalogger
' Program name: CS11-LManual60Hz.cr2
'date: Jun 2013
Const Samples = 25
' 25 samples for 2 waves of 60 Hz.
'Const Samples = 30 ' 30 samples for 2 waves of 50 Hz.
Public Crnt_A
Public mV(Samples)
Dim Counter
DataTable (Amp,1,-1)
DataInterval (0,1,min)
Average (1,Crnt_A,False)
Maximum (1,Crnt_A,False,0)
EndTable
BeginProg
Scan (1,Sec)
ExciteV (Ex1,mV2500)
For Counter = 1 To Samples
VoltSe (mV(Counter),1,1,1.0,-1250)
Next
ExciteV (Ex1,mV0)
RMSSpa (Crnt_A,(Samples-0),mV(1))
Crnt_A=Crnt_A*0.2 ' Multiplier for sensor
If Crnt_A<0.15 Then ' Eliminate noise below 0.15 amps.
Crnt_A = 0
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