84
active power Pa as an example, the communication value is read from the address [24][25], and the communication
value is 26000 from the address [26][27], that is, Val_t=1
×
65536+26000=91536 , the corresponding actual value is:
Val_s = Val_t / 100 = 915.36W.
4
、
Voltage and current harmonic data (voltage total harmonic distortion rate, current total harmonic distortion
rate)
Each electrical parameter occupies 1 WORD, and the correspondence between the communication value and the
actual value is
：
Val_s=(Val_t/100)%. Taking the total harmonic distortion rate of phase A voltage as an example, the readout
communication value Val_t is 157, then the actual value is Val_s=(Val_t / 100)%=1.57%, that is, the total harmonic
distortion rate of phase A voltage is 1.57%.
5
、
Energy data (primary side)
The value of the primary side of the energy is the floating point variable data type. It uses the sign bit to
represent the sign of the number, and the step code and the mantissa to represent the size of the number. The data
format adopted by the instrument is IEEE754 data format with 24-bit precision. The high bit 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, sign bit is the highest bit, and the mantissa is the lowest 23
bits.
Specific examples are as follows
：
Read number
：
0 10001110 100 1011 1010 1100 0000 0000b
Sign bit S=0
，
(
“
1
”
negative
，“
0
”
positive)
；
Calculation index E=10001110
，
Turn into a decimal number 142
；
Calculate mantissa M=100 1011 1010 1100 0000 0000
，
Turn into a decimal number 4959232
。
Calculation formula
：
The calculation result in the above example is：
10.2.2 About the GSD file description
GSD File access
：
The instrument's GSD file can be downloaded from the company's website at www.acrel.cn or from our
customer service.
CD mode is sent with the product
When configuring the PROFIBUS master station, after loading the GSD file of the APM series instrument, the
user parameters adopt the default values and do not need to be changed, as shown in the figure below.
Primary side electric energy
