27
26
D13= lsb zero corresponding to samplings of second frame (Current)
D14= msb zero corresponding to samplings of second frame (Current)
D15= lsb calibration factor relative to second frame (Current)
D16= msb calibration factor relative to second frame (Current)
D17= calibration factor exponent relative to second frame (Current)
I1...I200 = samplings relative to second frame (Current buffer)
CS = Modbus checksum
NOTE: Using the sampling values relative to Voltage and Current, the value of the measures of the different
quantities can be reconstructed. Formulas for a single-phase connection are given below:
E) DOWNLOADING OF VOLTAGE AND CURRENT WAVEFORM
The format of the string transmitted by NANOVIP PLUS containing 200 waveform samples is as follows:
E:0103 D1 D2D3D4 D5D6 D7D8D9 V1..V200 D10D11D12 D13D14 D15D16D17 I1..I200 CS CRLF
Where :
: =
start Modbus string
01=
NANOVIP PLUS default address
03=
data reading command
D1= number of frames inside the data buffer where a frame is equal to an entire sampling for one signal
(either Voltage or Current)
D2= type of signal identified by the first frame
D3= number of sampling data relative to first frame (LSB)
D4= number of sampling data relative to first frame (MSB)
D5= lsb zero corresponding to samplings of the first frame (Voltage)
D6= msb zero corresponding to samplings of the first frame (Voltage)
D7= lsb calibration factor relative to first frame (Voltage)
D8= msb calibration factor relative to first frame (Voltage)
D9= calibration factor exponent relative to first frame (Voltage)
V1...V200 = samplings relative to first frame (Voltage buffer)
D10= type of signal identified by second frame
D11= lsb number of sampling data relative to second frame (LSB)
D12= msb number of sampling data relative to second frame (MSB)
I
rms
=
1
200
2
k
2
x I x 0.0008579 x Calibration factor V x Calibration factor I x
x PT Ratio x CT Ratio / 1000
ENGLISH
VA = V
rms
x I
rms
Power Factor = W / VA
V
rms
=
1
200
∑
k=1,200
V
2
k
x 0.0008579 x Calibration factor V x PT Ratio
x 0.0008579 x Calibration factor I x CT Ratio / 1000
W =
1
200
∑
k=1,200
V
k
k
∑
k=1,200
V
