My 48VDC Siren Controller Build/Schematics

[Josh_S]

Hello everyone, it’s been awhile since I brought in any decent content here. While the board may not be as active as it once was, it serves as an awesome encyclopedia for anything siren.
I recently purchased a second T-128 from the city of Antigo (don’t ask about the first one). This time around I put in the effort of restoration. A dark grey paint scheme and checked all the mechanicals. Replaced the 1/4” screen with metal window screening like a 508. The unfortunate part about all of this was that the unit did not include a control panel. The city scrapped it long before the actual head came down. Then came the biggest electrical feat I’ve even encountered. I thought about different control variations. Batteries, rectifier, both. I decided that the battery route would be much more satisfying in a true backup form. I’d never worked on a siren battery bank, let alone my car battery (which I ended up having to replace mid siren restoration, go figure ). I compiled hours of research, diagrams, consultations (thanks to everyone who helped btw). Finally I was ready to purchase everything I needed and got going from there. I have around $700-800 invested in this including batteries so much more cost effective than a new or even used control panel. And it works! Almost perfect. There were some flaws with the cellular side of things, but we can blame a cheap Verizon hotspot for that. Anyways here we go.

The control design uses 4 group 24 deep cycle marine batteries. These batteries fit into a used electrical enclosure, on its back side much like a sentry job box deal. The main control board has two smaller enclosures. One for the main “guts” and another for the smarter side of things. It’s very relay heavy, since electronics aren’t one of my greatest feats.
The main things to note on the activation side, this siren uses a “smart” power strip capable of scheduling times and stuff per outlet. These outlets lead to 120V relays (one alert, one chopper attack, one rotator attack) that tie back into the main panel. The chopper attack relay is a macromatic brand timing relay with the timing set to 6on/6off. The smart power strip handles the alert/attack cycle length (ie: 3 minutes). The third outlet on the power strip is an “arm” feature. When the system is “armed” it applies power to the 48V power supply. This is the main reason for the power supply. If I “arm” the system for 5 minutes, I’d then set the correct cycle. Then I’d time the cycle for three minutes. Should the controls lose connection between these two, the siren won’t operate continuously because it’s set to “disarm” after 5 minutes.
The power strip, considering it’s near about in two middle of nowhere (the siren services about 100 households/businesses) gets its connection through a Verizon hotspot. Definitely hoping I can use it for a warning, but if not I get to test it weekly.
I won’t get any more in depth than that, should y’all have any questions I’d gladly answer them.
Here are the schematics:
https://www.flickr.com/photos/18785019 ... ted-public
https://www.flickr.com/photos/18785019 ... ted-public
https://www.flickr.com/photos/18785019 ... ted-public
https://www.flickr.com/photos/18785019 ... ted-public

[CanadianTbolt1003]

Very nice! if I were to build the controller that does alert and attack I would use electronic delay relays that you can hook up a push button to and let er rip for 3 minutes and when the timer for 3 minutes is up it all shuts down waiting for another push on the button to activate again this is what I did for my FS model D I made a replica of the PGA timer. Before going with these relays I tried using an Arduino clone and tried to make it do alert and attack with buttons but my lack of knowledge on coding and not knowing the Arduino needed more than just to put the push button on the digital pin and ground it needed 5V to keep it from false activations when I had a light switch around and I turn the switch the electrical noise interfered with the Arduino and the Arduino thought that was the push button signal and it sets it off because it was missing the 5V signal to keep it from triggering so I decided that it would be easier to go with timing relays. very good work on that controller!

- Sirens & Thunderbolts 1003

[Josh_S]

Very nice! if I were to build the controller that does alert and attack I would use electronic delay relays that you can hook up a push button to and let er rip for 3 minutes and when the timer for 3 minutes is up it all shuts down waiting for another push on the button to activate again this is what I did for my FS model D I made a replica of the PGA timer. Before going with these relays I tried using an Arduino clone and tried to make it do alert and attack with buttons but my lack of knowledge on coding and not knowing the Arduino needed more than just to put the push button on the digital pin and ground it needed 5V to keep it from false activations when I had a light switch around and I turn the switch the electrical noise interfered with the Arduino and the Arduino thought that was the push button signal and it sets it off because it was missing the 5V signal to keep it from triggering so I decided that it would be easier to go with timing relays. very good work on that controller!

- Sirens & Thunderbolts 1003

That’s a good idea! These are definitely ideas that I’d like to implement in the future. Once finances and time allows for a more permanent installation, this is how I’ll more than likely do it. And I’d use the WiFi controls for remote triggers and arm/cancel/tests.
As far as false activations, I’m still to this day worried something in the smart timer will go awry and set it off at 3 in the morning. But so far so good, and hopefully no false activations.

[uncommonsense]

This is so cool to read. It's a lot to digest. But the work you did is truly remarkable.