Web Console Configuration TCP alive check time
Setting Factory Default Necessity
0 to 99 min 7 min Optional
0 min: TCP connection is not closed due to an idle TCP connection.
1 to 99 min: NPort automatically closes the TCP connection if there is no TCP activity for the given
time. After the connection is closed, NPort starts listening for another host’s TCP connection.
Inactivity time
Setting Factory Default Necessity
0 to 65535 ms 0 ms Optional
0 ms: TCP connection is not closed due to an idle serial line.
0-65535 ms: NPort automatically closes the TCP connection if there is no serial data activity for the
given time. After the connection is closed, NPort starts listening for another host’s TCP connection.
This parameter defines the maintenances status as Closed or Listen on the TCP connection. The
connection is closed if there is no incoming or outgoing data through the serial port during the specific
Inactivity time.
If the value of inactivity time is set to 0, the current TCP connection is maintained until there is
connection close request. Although inactivity time is disabled, the NPort will check the connection
status between the NPort and remote host by sending “keep alive” packets periodically. If the remote
host does not respond to the packet, it assumes that the connection was closed down unintentionally.
NPort will then force the existing TCP connection to close.
At least, the Inactivity time should be set larger than that of Force Transmit timeout. To prevent the
unintended loss of data due to the session disconnected, it is highly recommended that this value is set
large enough so that the intended data transfer is completed.
Max Connection
Setting Factory Default Necessity
1, 2, 3, 4 1 Required
Max Connection is usually used when the user needs to receive data from different hosts
simultaneously. The factory default only allows 1 connection at a time.
Max. Connection 1:
NPort only allows 1 host to open the TCP connection to the specific serial port.
Max Connection 2 to 4:
Allows 2 to 4 host’s TCP connection request to open the specific NPort serial port, at the same time.
When multiple hosts establish a TCP connection to the specific serial port at the same time, NPort will
duplicate the serial data and transmit to all of the hosts. Ethernet data is sent on a first-in-first-out
basis to the serial port when data comes into NPort from the Ethernet interface.
Delimiter 1
Setting Factory Default Necessity
00 to FF None Optional
NPort 5400 Series User’s Manual
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