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2 cr200(x)-series dataloggers – Campbell Scientific CS10-L and CS15-L Current Transformers User Manual

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CS10-L and CS15-L Current Transformers

Do not average the waveform or use 60 Hz (or 50 Hz)
rejection. Under these circumstances, the amperage value
will always be zero.

CAUTION

Below is an example CR1000 program. In the program, a multiplier of 0.2 is
applied to the RMS value; see Section A.4 for more information.

'CR1000 program to measure rms current
PipeLineMode

'must be pipeline mode


Const num_samples = 100

'100 Samples @ 1000 micro sec = 0.1 second (5 @ 50Hz or 6 @ 60 Hz).

Public

Amps

'the line current

Public Amp_mult
Dim i_sig (num_samples)

'to hold the burst measurements, each 100 samples long

PreserveVariables

'to store values between power cycles


DataTable (AmpTable,True,-1)
DataInterval

(0,1,Min,10)

Maximum

(1,Amps,IEEE4,False,False)

Average

(1,Amps,FP2,False)

EndTable

BeginProg

Amp_mult = 0.2

'0.2 multiplier for the CS10-L

Scan (250, mSec, 10, 0)

VoltSe (i_sig (1), num_samples, mV2500,-1, True, 1000, 0, 1.0, 0)

StdDevSpa (Amps, num_samples, i_sig (1))

Amps = Amps * Amp_mult

'put in amps

CallTable

(AmpTable)

NextScan
EndProg

5.2 CR200(X)-series Dataloggers

The CS15 is manufactured specifically for the CR200(X)-series dataloggers. It
has an extra wire and requires an ExciteV instruction in the program. The
voltage excitation creates a positive reference output that the CR200(X)-series
can measure.

The recommended programming method for CR200(X)-series dataloggers
(where the scan interval is limited to once per second) is to place the VoltSE
instruction within a loop. The first CR200(X) example program has a loop that
samples 25 times, and the second CR200(X) example program has a loop that
samples 30 times. A 25-sample loop produces almost two cycles of a 60 Hz
wave form, and a 30-sample loop produces almost two cycles of a 50 Hz wave
form (see Figure 3). The average energy under the curve is calculated using
the RMSSpa instruction. A multiplier of 0.2 is applied to the RMS value; see
Section A.4 for more information.

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