HNC Electric HV610C Series, Руководство пользователя

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Appendix I H5RS485 Card & RS485Communication Protocol
This series of inverters provide RS485 communication interface and support Modbus
communication protocol. The user can realize centralized control through a computer or PLC,
set the inverter running commands through this communication protocol, modify or read function
code parameters, and read the inverter's working status and fault information.
I.1 Communication protocol
I.1.1 Protocol content
The serial communication protocol defines the content and usage format of the information
transmitted in serial communication. Including: host polling (or broadcast) format; host encoding
method, including: the function code of the required action, transmission data and error
checking, etc. The response of the slave also adopts the same structure, and the content
includes: action confirmation, return data and error check, etc. If the slave has an error when
receiving information, or cannot complete the action required by the master, it will organize a
fault message as a response and feed it back to the master. Application method
The inverter is connected to a "single-master and multiple-slave" PC/PLC control network
with RS485 bus.
Bus structure
(1) Interface mode RS485 hardware interface
(2) Transmission mode Asynchronous serial, half-duplex transmission mode. At the same
time, only one of the master and slave can send data and the other can only receive data. In the
serial asynchronous communication process, data is sent frame by frame in the form of
messages.
(3) Topological structure Single master multi-slave system. The setting range of the slave
address is 1~247, and 0 is the broadcast communication address. The slave address in the
network must be unique.
I.2 Protocol Description
The communication protocol of this series of inverters is an asynchronous serial master-
slave Modbus communication protocol. Only one device (host) in the network can establish a
protocol (called "query/command"). Other devices (slave) can only respond to the
"query/command" of the host by providing data, or make corresponding actions according to the
"query/command" of the host. The host here refers to a personal computer (PC), industrial
control equipment or programmable logic controller (PLC), etc., and the slave refers to an E300
inverter. The host can communicate with a certain slave alone, and it can also issue broadcast
information to all lower slaves. For the "query/command" of the master that is accessed
separately, the slave must return a message (called response). For the broadcast information
sent by the master, the slave does not need to feed back a response to the master.
Communication data structure
The MODBUS protocol communication data format of this series of inverters is as follows: