Is it possible to build a fire system without a firealarm panel?

Hello, I saw a diagram somewhere out there on the internet and for the life of me I cannot remember where I saw it but a diagram of a fire alarm system without a fire alarm panel, can this be done or is a fire alarm panel really needed?

A household fire alarm system consisting of smoke detectors interconnected so that when one senses smoke the sounders in all the detectors activate would not have a control panel.

Many, many years ago some jurisdictions allowed 3-wire fire alarm systems. In this case the pull stations are all in parallel as are the horns or bells. When any station is pulled all the signal devices will sound. Again, this type system does not have a control panel. Of course, these do not meet the requirements of electrical supervision of the wiring to initiating devices and notification appliances required for today’s systems.

This system that is hooked up in this apartment building has no central panel in order to reset the system if it trips. Instead, everything that would be connected to a panel is wired directly to the building’s electrical system. Of course, this is an AC system so I’m not sure if you wanted to know about DC systems.

If you are using household power, then you can hook up a system. The only thing is that the alarms have to run on 120 volts AC. I have a Simplex 4090-2 (as my signature implies), which is a 6" bell. The -2 means it’s a 120V model. It can run on household power. 120V systems are no longer up to code, so if you contact a fire alarm installation company, you can probably snag some 120V devices.