Communication Procedure; Using Tcp/Ip - Mitsubishi Electric A800-E Instruction Manual

(N) Operation via communication and its settings
Communication procedure

• Using TCP/IP

The following is the communication procedure when executing SLMP communication with TCP/IP.
With TCP/IP, connections are established when communication is executed, and whether data is received normally or not is
checked to ensure reliability of data. However, the line load is high as compared to UDP/IP.
Connection request
The external device issues a connection request
to the inverter. (Active open)
Sending a request message
Upon establishment of the connection, the external
device sends a request message to the inverter.
The process is repeated as needed.
Receiving the response message
The external device receives the response message
from the inverter and confirms the operation result.
Closing the connection
The external device issues a close request
to the inverter and closes the communication.
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PARAMETER
External device
Inverter
Connecting operation
The inverter accepts the connection request from
the external device. (Passive open)
Execution of the operation
According to the request message sent from
the external device, the inverter executes
a reading, writing, or other operation.
Returning a response message
Upon completion of the operation, the inverter sends
a response message to the external device.
Closing the connection
The inverter accepts the close request from
the external device and closes the communication.