HNC Electric HV590 Series, Руководство пользователя

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Appendix I H5RS485 Card & RS485Communication Protocol
host query / command. Host refers to a personal computer (PC), industrial control
equipment, or programmable logic controller (PLC), etc. The slave indicates HV590 inverter.
Host can not only communicate separately with the slave, but also broadcast messages
tothe lower machine. For separate access to the host query / command, the slave should
return a message (called the response), and for broadcast information issued by host
machine , feedback needs not to be responded to the host.
Communication data structure HV590 series inverter Modbus protocol communication
data format is as follows
：
using RTU mode, messages are sent at least at interval of 3.5
bytes times pause. In a variety of bytes in the network baud rate of time, this could be most
easily achieved (see below T1-T2-T3-T4 shown). The transmission of a do main is the
device address.
Transmission characters are hexadecimal 0...9, A...F. Network equipment continue to
detect the network bus, including a pause interval of time. When the first field (the address
field) is received, each device decodes it to determine whether sent to their own. At least
3.5 bytes times pause after the last transmitted character, a calibration of the end of the
message. A new message may start after this pause.
The entire message frame must be used as a continuous stream. If the pause time
frame prior to the completion of more than 1.5 byte times, the receiving device will refresh
the incomplete message and assumes thatthe nextbytewill be the address field ofa
newmessage. Similarly, if a new message starts in less than 3.5 bytes times following the
previous message, the receiving device will consider it a continuationof thepreviousmessage.
Thiswillsetanerror, asthevaluein thefinalCRCfieldwillnotbevalidforthecombinedmessages.A
typical message frame is shownbelow.
RTU frame format
：
START 3.5-character time
Slave address ADDR
Communication address ：
1~247
Command code CMD 03
：
Read slaveparameters
；
06
：
Writeslaveparameters
DATA(N-1)
Function code parameter address,function code parameter
number,function code parameter value,etc.
DATA(N-2)
………………………
DATA0
CRC CHK loworder
Detection value
：
CRC value
。
CRC CHK highorder
END
Atleast 3.5-character time
CMD(command instructions) and DATA(material words description)
Commandcode
：
03H
，
readsNwords(Thereare12characterscanberead atmost). For example
：
the inverter start address F0.02 of the slave machine address 01 continuously reads two
consecutive values.
Host command
ADR 01H
CMD 03H