NFC reader and alarm/door entry system

A long time ago I made a door entry and alarm system. Actually my first was approx 1989 using a mag head from a Sony walkman on a block of wood on the door and a wire wrap 6502. My latest attempt a few years ago is a lot more sophisticated.

It is good, indeed, I would say it is very good. It has a lot of off line working built in but backed by internet management/control system, so designed for power and internet failure, for hours, or even days.

The NFC door control uses AES on DESFire cards, so no plain text even on RF, and challenge both ways, so super secure. It even has different keys for each card. But it scales to any number of cards, with different access levels encoded in the card so as to work off line if needed (for a configurable time).

Like I say, it is good, and we use it, and a hack spare uses it (maybe two) and several small offices.

But it is tricky to sell.

Insurance and alarm companies have stuff tied up

Perhaps the biggest issue is that insurance companies and alarm companies have some industry standards and something of a private club. Yes, we could join, I am sure, but only if I wanted to be come an alarm company. Open source stuff is not going to get in to the club no matter how good it is. This is a shame as proper (Galaxy) alarm systems can be crap by comparison, as we know because we had one, installed by a certified installer, and were robbed!

My understanding is that one of the rules (I heard from an installer) was you can't have some external indication of armed or not. This ment staff did not understand they failed to arm. It beeps in various incomprehensible ways, and shows stuff on the keypad (which you cannot read from outside when using the fob to arm), so they assumed armed when not.

My system can show such, but we go for subtle - internal lights go off when armed. I mean you would turn off anyway, but staff can tell instantly that the lobby light not going off means not alarmed. The light switch does not allow manual turn off. Simple steps but has meant that on the odd occasion of not arming (e.g. fire exit open) staff knew. This is what caused the problem on Galaxy.

I also allow a forced alarm for such cases as a last resort - where the open fire exit becomes a sensor - someone closing it would set off the alarm. This means I can set forced alarm on timer, and be alarmed if staff have missed the problem somehow and still have a working alarm (all PIRs, etc). The Galaxy, when it does not arm, does not arm, end of story. It is a compromise I suspect an official system would not allow.

So basically you need to check (and record the call) insurance are happy with no proper alarm system, etc. Seems many are, and may not even charge more, but having it on record should mean you are covered.

Monitoring

Another issue is monitoring of the alarm. We had that once at an office, and it was such a pain. And one time when we did not know then code word, they said the police would be called. The police did not turn up so I was stuck there for 4 hours on a Sunday waiting for police. Also police won't come if you have too many false alarms.

My system monitors, but messages people, several people, like me, people with access to the CCTV who can confirm it is a false alarm, and if not call the police explaining they can see the burglary in progress on CCTV. That will, I expect, get a way better response than an alarm company calling.

Also much easier to integrate to external systems - staff in office logging for fire list, etc.

Locks

Another issue is locks, and the typical internal door lock is a mag lock, which is really easy to defeat. I have found much better locks and would recommend using them - Abloy locks. These work without the alarm and use a proper euro profile lock, and can be set to open from inside regardless, but also have a load of sensors (key used, handle used, lock in/out, etc).

Opening from inside also avoids the messy "break glass" and "exit button" you typically need.

So my system has to handle everything from a simple maglock and exit button, to the Abloy with something like 5 inputs - which it does nicely now.

It costs more, but in the end it is worth it.

Professional kit

With all of the above, an alarm or door entry system can work, with insurance confirming OK, etc.

But the kit is not as professional, or is it.

When I started I had single sided copper clad boards milled and hand soldered. I have moved on to proper PCBs made in China. I have moved on through a load of connector types to WAGO PCB connectors which are just simple to use for an installer. I have added per input/output LED status on the PCB.

But still, the case is a messy 3D print on my printer. Well, now we moved on finally with high resolution, smooth, clean, 3D resin prints from China.

The wiring and connector to the NFC reader was also a concern, but ironically the leads I got made in China for Faikin boards are perfect for this, and again, professional, so making it all easy to install and just more professional.

I finally feel like I have stuff that is professional looking.

The NFC sensor on a door. It looks proper now.

I have even now designed one for a 1 gang UK pattress box.

So now I plan to list these boards and cases on Tindie soon. The NFC reader is ideal for a hobbyist working on any NFC stuff.