Yokogawa PR300 Power and Energy Meter - Manual (Page 97)

< 6. Modbus/TCP Communication Protocol>
6-3
IM 77C01E01-10E
6.2 TCP/IP Communication
Modbus/TCP communicates with other devices, following the procedure below,
through the TCP/IP socket interface.
socket() socket()
bind()
listen()
accept() connect()
send()
send()
recv()
recv()
close() close()
Initial Setup
PC
Ethernet
PR300 with Ethernet
communication function
Open connection
Command
Response
Terminate
connection
Initial Setup
Figure 6.3 TCP/IP Communication
NOTE
If no request is received from the higher-level device for more than 60 seconds after estab-
lishing a connection, the PR300 will automatically terminate the connection.