Thank you very much.
For those who are looking for an answer here is the circuit diagram referenced from the links shared above:
https://www.shelly-support.eu/index.php?attachment/20990-image0-jpeg/&l=2
Often referenced as a 'bukowski' wire after the user who provided the solution.
Is it possible to set the input switch (SW) on a Shelly 1 so it only closes when full voltage (i.e. Live) is received, rather than on both neutral and live?
I understand that most Shelly units are set to 1/2 the input supply voltage to allow for neutral push-button action of the switch (Technical details on Switch input).
The use case is a bathroom extractor fan connected to a heat lamp circuit. The switch is wired so that if the heat lamp is on, so is the bathroom fan. The fan is also individually switched.
When wired with both switches off the input SW of the Shelly 1 closes on the N input from the light. (See attachment).
Open to alternate wiring suggestions as well.
