[tobiascapin]

Unfortunately I cannot have a SPDT switch to ground the signal when not pressed. Anyway finally I think I have solved using an extra external pulldown resistance of 10K.

I tryied to get direct support from Controllino, I had a first reply but I did not have any information related to internal resistence. The documentation has not information about this requirement and moreover has no information about the internal pulldown resistance value.

I’m really disappointed with the lack of documentation and of the support.

[tobiascapin]

Dear Lukas, I did not find the value of these internal pull-down resistors in the documentation.
By the way seems I have solved with an additional external 10k pulldown resistance, I agree the problem was an high noise due to the long wire.