That’s right, I do remember something about shelly1’s working in LV applications.
So you are essentially using reed switches to pick up the B-field emitting from the solenoid coils? …or did you stick magnets to the ends of the plungers or something like that? The former seems like it would be really dicey depending on the coils and placement of the reed switch, the latter might have issues with interfering B-fields.
On a related weak signals note… I mentioned really like frencks insight using the relay coil in series to create a positive binary signal. However, I think that method may not work so well with modern chimes. Lots of newer doorbell chimes use efficient circuits with speakers/amplifiers for output, instead of the classic solenoid and bell. These modern chimes draw an angel’s fart worth of current compared to their solenoid counterparts. Complicating matters, on these modern chimes the current draw may not directly coincide time-wise with button contact (you may read some short blips, rather than a sustained button press). This makes reliably reading bell signals on some chimes very difficult; it’s the reason I had to resort to using a hall sensor for my home.
Ah, lol I skimmed over that a while ago and inferred that’s what frenck was doing there. So I guess came up with the idea of using the coil as a sensor on my own!
Yeah that being the case, my post directly above is incorrect regarding this working with modern bells (edited accordingly). The only thing that sucks, is lighted doorbells won’t be lit up that way. Perhaps a solution to that, is keeping the button wired to 24VAC, then using a divider on an analog pin together with some basic signal processing to read it. Shouldn’t be too intensive being it’s just 60hz (my hall sensor code only needs one complete wave cycle to read reliably… ~20msec… one could use interrupts instead).
I unfortunately am using Iris 3320-L contact sensors… (because I had gotten a bunch very cheap) and they use a Hall effect sensor instead of a reed switch like most to detect the magnetic field which does make it pretty dicey… which is why I was looking for alternatives… I had bought the Shelly1s in a two pack a long time ago but never used them… so I was hoping to make use of them finally. My doorbell with the iris works about 98% of the time so it’s not a huge deal… but once I remembered the shellys sitting in a box I started thinking of how I could make use of them.
I am not using it to detect or monitor a doorbell button press
I wanted to something to use as a momentary switch to replace the doorbell button so I can use my old wireless doorbell transmitter to trigger the receiver units in the house and have the hub “press” it when it detect another doorbell being pressed.
I already have a sensor in my doorbell chime which is monitoring it.
Make senses? I know it sound backward but it what I am trying to do for this project …
