`
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table:
Example 1：Read a phase voltage UAN,read the data stored in the address 243 colimn to read the
data,that is,the communication read out value Val_t＝3800，read PU＝100，Ue＝400，so Val_s＝
Val_t*PU/Ue＝3800*100/400＝950V．
Example 2：Read a phase voltage UAN,read the data stored in the address 243 colimn to read the
data,that is,the communication read out value Val_t ＝ 3800 ， read address 13-14 voltage facto
Ratio=0.25，则 Val_s＝Val_t*Ratio＝3800*0.25＝950V．
7.5.2Active power,resctive,apparent power and electric energy
The series of measured values are read out by the 0X03 command of the MODBUS-RUT communication
protocol,and each item occupies two word.The correspongence between the communication value and
the actual one-time side value is as follows：Val_s＝Val_t / 100；Val_t＝the first word×65536+the
second word。
Example 1: read
A phase active power Pa,the data is stored at address 253-254:the read value of
address 253 communication is 1,and the readout value of address 154 is 26000.Read PU＝100，
PI＝1000，Ue＝400，so Val_t＝1×65536+26000=91536,so Val_s ＝Val_t*PI*PU/Ue/10＝2288400W.
Example 2: read
A phase active power Pa,the data is stored at address 253-254:the read value
of address 253 communication is 1,and the readout value of address 154 is 26000.Read address power
and electric energy coefficient of 18-19 Ratio=25，so Val_t＝1×65536+26000=91536,so Val_s ＝
Val_t*Ratio＝2288400W.
7.5.3
Voltage wave peak coefficient,telephoe wave form factor,current K coefficient,voltage
wave peak value,current/voltage positive sequence negative sequence,zero sequence
component and unbalancedness.
This series measuring value is read out by Modbus-RTU protocol 0
×
03 command,each item occupy
one word.Relation between communication value and actual value is shown as below table
：
Applied parameter
Relation
Unit
Voltage
Uan、Ubn、Ucn、Uab、Ubc、Uca
Val_s＝Val_t * PU / Ue
V
CurrentI
A
、
I
B
、
I
C
Val_s＝Val_t * PI / 1000
A
Power factor
PF
A
、PF
B
、PF
C
、PF
总
Val_s＝Val_t / 1000
None
Frequency
FR
Val_s＝Val_t / 100
Hz
Applicable parameters
correspondence
unit
Power
Val_s＝Val_t * PI * PU / Ue / 10
W、var、VA
Electric energy
Val_s＝Val_t * PI * PU / Ue/10
kWh、kvarh