Homemade fire alarm panel

Using my super basic electrical knowledge I’ve put together a single zone, unsupervised hobby fire panel. It works with any conventional heat detector and pull station, as well as conventional 4 wire smoke detectors.

The bottom relay is just to control the AC Power indicator. The top left relay is wired into the negative leg of the Alarm Zone, so if any initiating device is activated it will send 24VDC into the relay, activating it. This will also activate the top right relay which acts like a simulated pull station keeping the Alarm Zone shorted out. Meaning even if you reset the initiating devices the panel will remain in alarm until the reset button is pressed. The reset button is the normally closed switch from a BG-10 pull station. When depressed it will open, cutting power to the alarm zone, deactivating both the alarm relay, and alarm latch relay. As long as all initiating devices are reset the panel will return to normal. The detector reset switch works in the same way, cutting power to the Auxiliary 24V terminal causing any field detectors to power cycle and reset. The alarm silence is a simple toggle switch which toggles between sending 24VDC to the NAC’s when activated, or a silence indicator light when deactivated.

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That is one of the best homemade fire alarm panels I’ve ever seen. Do you plan on making a demo system? What is that being used for the cabinet?

Does it work with real conventional devices like pull stations and notification appliances as well?

Thank you! The cabinet used to be an Edward’s BPS power supply. I haven’t created a proper demo board, just tested it with loose devices wired into it.

It will work with any 24VDC Notification Appliance. And any conventional pull station or heat detector. And if you use a 4 wire smoke detector like a 4W-B you can wire smoke detectors into it.

That looks really good and clean! Can’t wait to see if this evolves into more!