How to link 50 or more 120volt Smoke Detectors in a mulit-room facility?
on BRK and Kiddie they have limits to how many you can interconnect, any thoughts?
I'm sure many of us here in the Forum can figure out creative ways to link all these devices together as you would like. The short answer is they would all be in violation of not only the NEC but I'm sure local fire & building codes. You might as well get it into your head right off the bat and install a fire alarm
system as Kwired pointed out. You'll come out with a better, more reliable system in the long run.
There's also the issue of liability. After you're done twisting this togetrher, installing relays, interfacing the relays with sirens, etc. are you going to affix your company name to this 120 v "system" you designed? If the system should happen to fail and someone gets injured or perishes due to that malfunction do you really think the judge at your trial is going to accept "Sorry Your Honor, it was my design and I really thought it would work" ?
I'm not trying to break your chops here, I just want to set you straight. The liability of doing what you want to do is greater than what the job is worth IMHO.