Hello,
I am trying to establish the limits of the 6ES7131-7RF00-0AB0 SIMATIC DP, ELECT. SUBMODULE
FOR ET 200ISP, 8 DI NAMUR

What are the frequency limits of the DI inputs on this card?
i.e. what is the limiting high freqency at which the card no longer registers the input?

Thank you for your help

Input delay

• for "0" to "1" 2.8 ms to 3.5 ms

• for "1" to "0" 2.8 ms to 3.5 ms

But this is only a part of the problem. You need to take the complete reaction time into account, Profibus rotation time included.
In the same manaul in annex A3 there is a short introduction to the topic.