Exact!

It works as you say.

It's a shame that communication is so laborious.

This mystery solved.

Is what I want to do possible?Namely, stopping the fan when the door is opened, and adding the speed switch?

When I test the program with the door button or with the speed switch, the LOGO makes a sound which is really not reassuring and the motor does not turn.

Can you confirm my connection?

Door button: one terminal on the LOGO power supply the other on I1.

Speed ​​switch: terminal C on LOGO power supply terminal 1 on I2 terminal 2 on I3.

Pfff, I'm an ***.I mixed up the entrance and exit, sorry.

Fortunately, Siemens products are quality products! Itested the terminals and they all work.Phew!

Your program works in terms of managing thresholds and door swich. It doesn't work for speed switch.

In the attached program, nothing works in terms of threshold management and door swich, but the speed switch works.

While from what I see, in both cases the simulations are good...

To modify the temperature thresholds, are these thresholds B002, B003, B004, B005, B009?

Correct or almost.

Below 20°C the fan runs at 10Hertz.

Speed ​​switch works.

Position 1;30Hertz instead of 25.

Position 2;50Hertz is OK.

Sorry it took so long.