Veichi Electric AC60 series, Руководство пользователя

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RS485 hardware interface
(2)Transmission mode
Synchronized serial，half-duplex transmission mode: The host machine and
slave machine can only one sends the data and another one receives at the same
time. Data in serial synchronization communication process is dispatched one
frame by one frame in the format of message.
(3)Topology structure
Single host machine with many slave machines system. Setting range of
slave machine’ address is 1 ~247. 0 is broadcast communication address. The
address of each slave machines in the network is unique. This is the basis
to ensure ModBus serial communication.
5. Protocol specification
The AC60 series frequency inverter communication protocol is that a kind
of master-slave ModBus communication protocol of synchronization serial, Only
one equipment (host machine) can build up the protocol in the network (can
be called "inquiry/ order "). Other equipments (slave machines) can only
respond to the host machine "inquiry/ order " by providing data, or make
corresponding action according to the “inquiry /command” of host machine.
Host machine here is the personal computer (PC) , the host station frequency
inverter , industrial control equipment or programmable logic controller (PLC)
etc. Slave machine here is the AC60 series frequency inverter or other control
equipment with identical communication protocol control system. The host
machine can carry out communication with one slave machine, or announce
broadcast information to all the slave machines. Slave machine have to return
one piece of information (is called responding to) while visiting "Inquire
/ command” of the host machine alone. But slave machine unnecessarily feedback
responding information to the host machine while the host machine send the
broadcast information.