Legal to have a hobby system.

Hi Again! :slight_smile:

I was wondering if it’s legal for me to build my own hobby system and if I could wire it myself or do I need to get a professional to do it.

150th post!


It’s not necessarily “legal” to build a demonstration system, but it’s not something the police are going to break your door down over. If you know how to wire your system up, then you don’t need a professional. Is this system going to be installed on a board or in your house? Just know this:

In other words, if you want a demo system, by all means set one up if you know how, but don’t install it in your house thinking it will replace your existing residential smoke alarms, especially if you do not have experience in this field.

Nothing’s stopping you from installing a hobby system in your house, but I don’t recommend it. The risks may be unlikely, but not worth it in my opinion. These are some scenarios in which you could run into trouble:

  • You sell or add on to your house, and a home inspection reveals the remnants of shoddy installation work which raises questions from the AHJ. Probably nothing, but it’s best to avoid any red flags when it comes to local government. You don’t want something like that to delay you from getting an occupancy permit.
  • System goes off while no one’s home and neighbor calls 911. FD comes inside and silences system. Questions are raised from the fire marshal. Fines may be involved.
  • Your house catches on fire and the FD reports finding an unlicensed commercial fire alarm system inside. Word gets back to the insurance adjuster whose job is to look for every reason possible to lower/deny your claim, and you’re screwed. The situation would be even worse if your fire alarm system is what caused the fire.

    The quote above is the best advice to heed. Build your system on a plywood board with 4 toggle bolts to attach it to the wall. That way, it can be easily removed if you go to sell your house and you’ll only have to patch 4 small holes. Use a plug and don’t mess with any romex wiring in your walls unless you’re a licensed electrician.

The wings on some of those toggle bolts can get very large… they don’t leave gigantic holes in the wall, do they?

It’s gonna be mounted on a board and I found a app where I can silence it when im not home. and it’s gonna be a demo system using my 4001. And no I don’t plan on using it to replace my home fire alarm system my dad installed.

I would recommend leaving it unplugged unless you are near it, in case something goes wrong.

What’s the app called? I’m pretty sure that Simplex never made an app for an iPhone that silences 4001-series panels :stuck_out_tongue:

It a custom app made by my friend he might make it on the App Store though

And how dose it work with the 4001??? :roll:

The wings fold in as it slides into the hole. I used them on my board and drilled 1/4" or 1/2" holes - an easy patch job. I installed it in a room that will need to be painted anyway before we eventually sell the house.

Aruindo he says



If you’re thinking something like that ^, that was a custom designed system from the ground up. That panel just so happens to use the serial connectivity on the Arduino. The webpage design only lasted for that system test and the files are gone but not missed.

Those are some words of wisdom! :slight_smile: Anyways, always mount your “play” system on Plywood and make sure the power source is easily removable. If possible, don’t mount the plywood to your wall . Lean it up again your wall or hang it up in closet so it is portable and can be move around (or out if necessary). Also, always remember to disconnect the power when the system is not in use.