Mitsubishi Electric fr-e700 series, Instruction Manual

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Parameter MODBUS®/TCP (FR-E700 SC ENE)
FR-E700 SC EC/ENE 6 - 333
6.23 MODBUS®/TCP (FR-E700 SC ENE)
The MODBUS®/TCP protocol allows transmission of MODBUS messages via Ethernet communication.
Communication specifications
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The communication specifications are given below.
Initial setting
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To select MODBUS®/TCP for the application, set "0" in any of Pr. 833 to Pr. 835 "Ethernet function
selection 1 to 3". (Refer to page 6-285.)
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To limit the network devices that send the operation or speed command through the Ethernet
network (MODBUS®/TCP), set the range of IP addresses (Pr. 844 to Pr. 849). (Refer to page 6-289.)
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Set the interval of the communication check (signal loss detection) time in Pr. 852 "Ethernet
communication check time interval" for all devices with IP addresses in the range specified for
"Ethernet command source selection" (Pr.844 to Pr.849). (Refer to page 6-290.)
Message format
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Query
A message is sent to the slave (the inverter) having the address specified by the master.
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Normal response
After the query from the master is received, the slave executes the request function, and returns
the corresponding normal response to the master.
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Error response
When an invalid function code, address or data is received by the slave, the error response is
returned to the master.
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This response is appended with an error code that indicates the reason why the request from the
master could not be executed.
This response cannot be returned for errors, detected by the hardware, frame error and header
check error.
Item Description
Communication protocol MODBUS®/TCP protocol
Conforming standard Open MODBUS®/TCP specification
Waiting time setting Not used
Maximum number of connections 3
Slave function (server)
Number of simultaneously
acceptable request messages
1
Tab. 6-121: MODBUS®/TCP communication specifications