Sensing doors and windows is essential for the burglar alarm function. Theses sensors are small, cheap and easy to mount yourself to secure your house. Furthermore, they are very nice to have when trying to remember if you've left something open and when. Mounting door and window sensors is the fastest way to make your home smarter and make you more secure.
What it looks like!
Door and window sensors are the same, and they look the same. White, square, and approx 4 centimeters wide. It is composed by two pieces. The small slim magnet (in top of picture below) and the sensor electronics (lowest and largest piece in picture).
And how it looks in real life!
When mounted, it can be "camuflaged" in a corner, the door post or window frame. The magnet of the sensor is very slim and therefore easy to fit to modern windows with an esthetic anonymous look.
What does it do?
When the magnet is moved away from the sensor, about 1cm, then it "triggers" as opened. You close it by moving the two pieces closer than 1cm again (on the side of magnet with an arrow and where the magnet visually fits).
A radio signal is sent from the sensor when triggered by opening or closing the door. This is how the burglar alarm will know if someone enters your house through that passage.
Installation basics
A door or window "splits into two parts" when you open it. By mounting each half of the sensor on each part of the door/window, then the sensor parts will also move away from each others when you open, and together when you close.
All you have to do, is to stick either the magnet or sensor on the part of your door/window which moves when you open, and the other to the static frame. Just make sure they are within approximately 1cm when you close.
You can easily check if the sensor detects open and close by looking at the red LED on the sensor. It will light up when opened and closed (a bit hard to see in sunlight).
The sensor has a sticky backside to make it very easy for you to place it.
How to make it even smaller?
You may also mount it like in this picture, to make it take up even less space on slim frames. The magnet part also works when placed on top of the sensor part.
Can it do other things?
You can check your app, and see when a door has opened or closed - what time your kids came home or left. You do not have to go upstairs to check if a windows is closed for rain - just use your app.
Notify me on open windows when I leave!
We admit it. We miss the feature of warning you on open doors and windows when you leave and arm your security system. Read more about the current status in our section on ideas and future.
How do I test it?
The system automatically monitors your door and window sensors. You will be notified if they run out of battery, their signals get weak, or someone has removed or destroyed them. 1-2 times a day, the cloud will double-check to see if all is ok.
But, if you want to check too, then click "test" in the app and follow instructions there, or simply open a door, check if the red LED lights up and if your app shows it is open.
Typical weakness!
If someone removes the magnet, then it will not trigger alarms when the door is opened. Unlikely maybe, but still a weakness. You can check this in the app, by going through your doors and windows to see if their open/closed status is correct. If the app says open, but door is closed, then check the magnet.
Magnets can be tampered with, by use of other super strong magnets. It is hard to simulate the same magnetic field through a closed window or door from the outside, but still possible in theory.
Batt low, how to replace?
The battery (normal CR2032) is located inside the sensor part. Use a screwdriver to gently open it.