daviteq Sigfox WSSFC-AC FW1, Руководство пользователя

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Re-calibration / Re-validation Yes
The transducer may need to be re-calibrated when
necessary. Please refer to this link for the procedure of
calibration.
The Daviteq Sigfox-Ready AC current sensor comprises 02 parts connected together as shown below picture.
- The Daviteq Sigfox-Ready wireless transmitter;
- The Daviteq AC 5A current Transducer;
The AC current transducer is to measure the actual AC current of the secondary winding of the CT.
The Sigfox-Ready is to read the AC current value from the transducer and perform the scaling (A and B values, during
calibration). The scaled current will be multiplied by the CT ratio to deliver the final value which is the actual load
current that the user wants to measure.
Scaled_CT_Current = A x CT_C B
Actual_Load_Current = Scaled_CT_Current x CT
Where:
A : Constant A
B : Constant B
CT_current: the measured current from the transducer (Secondary winding current of the CT)
3. Advanced Guide
3.1 Operating principle of the Sigfox-Ready AC current sensor
3.1.1 Operating principle of the complete device
For example: the CT_current = 1.5A, the CT ratio = 20 (the CT is 100/5), A=1, B=0 ==> then the
Actual_Load_Current = 1.5 x 20 = 30A
Note: the Low cut value of Actual_Load_Current is 0.5A. That meant the device can not measure the current
load less than 0.5A