Hi all,
I recently replaced one of the smoke detectors in my home (basic "First Alert" smoke detector 9120FA, has the interconnect feature) ... started making several beeps indicating that the detector has reached its "end of life." I would love to re-purpose this detector and use it for the piezo alarm inside, NOT as a smoke detector as I know this is unsafe. I was thinking something along the lines of a "door alarm."
Firstly, I'd love to understand how these detectors know they have reached the end of life, and is there a way to disable this feature along with the ionization detection? I realize each brand and model is going to be different, but the bare bones detectors probably have a lot of similarities... hoping to get some general advice.
If I re-purpose this detector, I do not want it constantly chirping from the end of life feature (annoying) and if I use it in my garage I do not want the alarm going off each time I start the car. I'm thinking I can simply trigger the interconnect line to set the alarm off... this way I can easily interface with the alarm (just need to pull the interconnect line high when the door opens).
If anyone has any experience hacking into these things that would be great!
(Also, I realize I can just pull out the piezo and build some kind of driving circuit for it, but the goal here is to learn about how the detector works, along with hopefully being able to easily modify a regular detector)
Thanks!