@barnabás-králik said in About the relays:
I'm thinking about using an L403 for controlling a large number of blinds (apart from other building automation duties) with 2 relays per blind motor.
Why not go for TCP-IP solution, i use a Kincony kc868-h32, a 32 relay solution, that you can steer the relays true a url link command, works fine for me.
There are similar solutions more hobby orientated, and more pro, over Modbus, serial and TCP-IP, there are also 2/4/8/16 solutions out there, so that you can have your relays close by what you wane control, and only have to run a network or serial cable to the relay unit.
https://www.youtube.com/watch?v=RVWvRN8yKWs
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