optimal value for Poll interval in Modbus TCP/IP

[khalil]

Hello Dears,
I have Modbus TCP/IP for Pumps Control.
I set the poll interval to 5 seconds, but I need to make it less for fast response.
what is the optimal poll interval and does the LM, SL overloaded if it become like 1sec.

I have 8 devices connected on the Modbus TCP/IP port.

[admin]

Poll interval value depends on the task. You can make it lower but it's impossible to get really fast reaction time as Modbus values have to be constantly polled.
Another thing to consider is that all devices are polled one after another in a single queue. So if you have a lot of data points the actual time between polls can be higher than the set poll interval.

[khalil]

Thanks admin.
So I can set it to 1sec but consider extra delay depend on the number of devices

[admin]

Yes, you can use 1 second poll interval.