How to define a "deadbolt zone"?

Just thinking out loud... ignore my ramblings if you want. :)

Do you even need a rare earth magnet? Most deadbolts are steel, right? Can't we just find a way to magnetize them?
Interesting thought politics123. I'm not sure how one would do this and make sure that it does not get demagnetized. I found this article:

Making a permanent magnet

however one comments after that they demagnetize easily. One would hate that to happen and set off the alarm.

But nice idea. Maybe someone else may know how to do this.

On another note, I'm not sure why deadbolt sensors are not a standard item on all residential security systems. The installer could make more bucks on the wiring, sensor and extra zone requirement. I'm sure that anyone would want to know that the deadbolts are in.

My home was security prewired several years ago on construction and I only recently put in an Elk system. I did not even think about deadbolt sensors at construction by when I wired up the doors, then they occurred to me. Luckily the security prewire had 4 conductor cable (probably standard in a prewire) and this is why I was able to wire both the door sensor and deadbolt sensor separately. I did have to run a wire between the door sensor and deadbolt sensor but it isn't that noticeable below the weatherstripping.
. . .I've attached a photo I found of a switch similar to the one I purchased locally. It uses a "roller lever" to provide less resistance and more leverage. . .
I used 123's approach because I had these switches on the shelf and had some installation clearance challenges. Alignment was not difficult but any future adjustment could be troublesome. Also you obviously don't want the deadbolt to slam the switch or durability will suffer.

I agree there are nicer solutions as documented in these related posts, including a horizontal mounting of the microswitch (has anyone actually done this?), and the GRI plunger switch, and the optical sensing.
[topic="11575"]Status of exterior door/gate locks[/topic]
[topic="4290"]Deadbolt Sensor, Is there such a thing?[/topic]

"A" shows bolt thrown, "B" shows bolt withdrawn.


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I realize this is a rather old thread, but...

One more sensing technique to add to the list - Inductive.

I was looking for a solution to sense when my Pella Slider footlocks were engaged. I ran across the following Inductive sensors: Inductive Proximity Sensor

The use a coil which senses a change in the resonant frequency when a metallic object is within view. I've tested them with a variety of metals (carbon steel to aluminum) and although the sensing distance changes, they will still switch. One of the things that I really like about these is that they are very "selective". I have an installation on my front door deadbolt where the sensor is surrounded by metal on three sides (metal doors with sidelites). It ignores the structure of the side panel and senses only the presence of the deadbolt.

For the footlocks, the sensor detects the metal pin when the footlock is in the engaged position. The sensor is small enough to allow me to mount it on the back (underside) of the footlock. It senses the metal pin through the plastic body, but is unaffected by the surrounding screws and mechanism.

These are available in both NPN and PNP outputs (I'm using both with the ELK-M1). My slider installs are over a year old now and I've had no issues (no adjustments or false reports).


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