P, Pc, Pb, Pa) read.
4.Power factor values PFA, PFB, PFC, PFsum:
Val_s=Val_t/1000，No unit
5.Frequency:
Val_s=Val_t/100，Unit Hertz Hz
6.Electrical energy:
For the AMC series intelligent power collection and monitoring device, the following a and b methods can be
used to read the electric energy, and the user can select according to the actual situation.
a) Read address 003FH～0040H (absorbed active energy), 0041H～0042H (release active energy), 0043H～
0044H (inductive reactive energy), 0045H～0046H (capacitive reactive energy) secondary energy, read again PT,
CT, calculated according to the following formula:
Electrical energy communication readout value Val_t=first word × 65536 + second word
The primary value of electric energy is Val_s=Val_t/1000×PT×CT, the unit of active energy: kilowatt hour
(kWh), and the unit of reactive energy: kilowatt hour (kvarh). The PT is read from the address 0003H, and the CT
is read from the address 0004H.
Note: In general, the user reads the absorbed active energy.
b) Read the primary side energy in 0047H~004EH. This value uses the floating point variable data type. It
uses the sign bit to represent the sign of the number, and the exponent and mantissa to represent the size of the
number. The data format adopted by the meter is IEEE754 data format, with 24-bit precision. The high order of
the mantissa is always "1", so it is not saved. The bit distribution is as follows:
1-bit sign bit, 8-bit exponent bit, 23-bit mantissa, the sign bit is the highest bit, and the mantissa is the lowest
23 bits.
Specific examples are as follows:
Read number (such as 047H 048H, 2word, from high to low, total 4byte, 32bit):
0 10001110 100 1011 1010 1100 0000 0000b
Sign bit S Index position E mantissa M
The sign bit S=0, “1” is negative and “0” is positive;
Calculate the index E=10001110, and convert it to a decimal number 142;
Calculate the mantissa M=100 1011 1010 1100 0000 0000, and convert it to decimal number 4959232.
Calculation formula: primary side charge
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