[OFS3.31]OFS tries to open connection when momentum close it

Goals and Symptoms:

System setup: OFS (v3.2 or v3.3) is used as a central data collector Momentum CPU's (60) are used as decentral RTU's. Communication from CPU's to OFS-central should be " On exception" using Modbus/TCP.
OPC server is set-up for Push data support, to have the possibility to send data from the Momentum on exception. Problem description: At startup of OFS, a TCP connection is made with the Momentum CPU's for the quality check. This is regardless of the 'quality check' rate setting. This connection is not closed. When the Momentum sends data, it will open a new connection to OFS on port 502, sends data and closes this connection with a TCP FIN command.

However the TCP connection which was opened to the Momentum (for an unknown reason), will be closed by the Momentum after 10 seconds using a TCP RST command (this is built into the Momentum firmware to prevent multiple unused open sockets). This will cause the OFS server to show the device as BAD and try to reopen the connection.

Question: We want to use this setup to connect multiple PLC systems to a central database, and have communication only on changes. Because the TCP connection, opened by OFS at startup, this setup is not working properly. Is there a way to prevent OFS opening a TCP connection (socket) when only Push data is needed or else is it possible for Ofs to close the socket when when the quality check is complete?

Causes and Fixes:

For the items included in the Push data range, the Quality attribute is identical for all items and may be:
+ Always defined as Good (if the "Quality Check Rate" value defined in the device
properties page is equal to 0),

+ Defined according to the communication status and the operation mode of the device (if the "Quality Check Rate" value defined in the in the properties page of the device is defined as NN and not as 0). Every NN seconds, the server will attempt to read the operating mode of the device:
- In the case of failure of the communication, the quality is defined as Bad,
- If the communication is established and if the operating mode is defined as RUN, the quality is defined as Good,
- If the communication is established and if the operating mode is other than RUN (generally this means STOP), the quality is defined as Uncertain,

The Quality Check Rate option is only available for PLCs of types Concept, PL7
on X-Way and Unity Pro.


Q: Because the TCP connection, opened by OFS at startup, this setup is not working properly.
R: The first connection is mandatory because OFS has to open a socket to listen on it.

Q: Is there a way to prevent OFS opening a TCP connection (socket) when only Push data is needed or else is it possible for Ofs to close the socket when when the quality check is complete?

R: For the customer s setup, you should set the Quality check rate parameter to 0 in order to keep the GOOD quality on the device.

However, OFS will still try to open connection when the momentum will close the connection every 10 seconds. But we don't have a solution of configuration in order to avoid it.