A motion detector registers a movement and then triggers the alarm. This can be in the form of a visual or acoustic signal, there are also links to alarm systems, which then send a notification.

In this article, we present variants of motion detectors, functionality, tips for installation & Co.

The Most important thing in advance:

  • Motion detectors can be installed in the home or outdoors . Often they are coupled to lights or are included in alarm systems
  • In order for them to fulfill their function, they must be set correctly so that they do not sound the alarm when a cat is present, for example
  • The installation is either flush-mounted or they are plugged into an existing socket
  • As soon as they detect movement, they sound an alarm (light, sound, message).
  • For private individuals, infrared motion detectors are well suited: Functional, easy to install and inexpensive
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Types & operation of motion detectors

The How motion detectors work differs depending on the technology used. As a result, they all have in common that a movement is registered. How they detect this, however, works in different ways:

  • Passive Infrared Detectors (PIR): Through a change in the detected infrared radiation, motion is detected. The heat from animals, Machines and people radiates into the environment, this can be detected by the infrared radiation can be detected. However, this only applies to objects that radiate heat. So if an object has the same ambient temperature, no alarm is triggered. In practice, however, this is completely sufficient, because one is also rather be stolen by a human being, i.e. by a tree..
  • RF/radar motion detector: Here, electromagnetic waves are actively emitted and the reflection of these waves is detected. The advantage of this technology is that the waves can also penetrate through materials such as glass or wood. Thus they can be applied in a concealed manner

Infrared motion detectors are widely used due to their ease of installation and reliable results, and are the most suitable for home users. Often, different technologies are also combined to achieve an even better result.


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Installation flush-mounted or retrofit motion detectors?

The installation of motion detectors is an important point in the purchase decision. There are there are actually only two variants:

  1. Flush-mounted installation: Flush-mounted installation (during construction or major renovation) is costly, especially if the motion detectors are installed retroactively and not during new construction. The clear disadvantage is the cost. Advantages are that the motion detectors can be installed invisibly. In addition, no sockets are required and possibly the appearance is better.
  2. Subsequent installation: Here the motion detectors are simply plugged in, aligned and linked to an action (e.g. light on). This type of installation should be sufficient for the vast majority of private users. Even if a motion detector should be obvious upon closer inspection, this may even deter or can be remedied by multiple layers of security.

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What is there to consider when installing?

The Installation flush-mounted should be done by a professional. For place, Angle, type of concealment should necessarily be assessed by a professional. Basically should be observed during installation the following points

  • Burglars enter through a window, a door, the garden etc.. These “entrance areas” should therefore definitely be detected by the motion detectors so that they also provide burglary protection. Furthermore, a detector can be installed in very sensitive places (e.g. living room with valuables)
  • The detectors should be placed in the corners, high up. So you can not “sneak” around the motion detectors.
  • The devices should not be covered by furniture, edges, plants, etc. (although some detectors can handle it – better not to cover).
  • It is best to choose a model that will blend into your home without attracting attention (size, color, cable color, etc.)
  • If motion detectors are installed later, think also about free socket places, sufficient cable length, if necessary cover for the cables.
  • Make sure that the outdoor motion detector is protected from direct rain

Buying tips

So that you find a model for you, you should pay attention to the following points

  • Weatherproof: Consider that in your garden or patio area wind and weather will affect the detector affect the detector. Therefore, you should look for a model that can withstand rain and cold can withstand rain and cold
  • Installation: Where should the device be installed? Do you still need a dowel and a screw? Is everything already included in the scope of delivery?
  • Power source: Do you need a connection to the mains? Is the cable length sufficient for this? If you have a battery-powered device, remember to charge or change the batteries Batteries at regular intervals
  • Settings: Can you adjust the intensity of the detector and other alarm settings (brightness, volume)? (brightness, volume)? This way you can reduce the number of false alarms.
  • Detection angle: How wide is the detection angle of the lens, also called pyrosensor? called? For corners 90° are enough, for wall surfaces 180° or for an installation on the ceiling 360° are required for installation on the ceiling.
  • Brightness: The brighter the light, the more conspicuous an alarm appears. Therefore, pay attention to a correspondingly high luminous power or a high number of watts.

For a good Model requires an investment of 20€ to 80€

Buy motion detector

If you want to your own four walls with motion detectors, you can choose from a wide choose from a wide range

Set motion detectors correctly

So that the Motion detector works correctly, a few settings must be made must be made:

  • Range: The range of motion detectors can be adjusted. This can make sense, for example, if movements of the neighbor or a street are detected are detected and this results in frequent false alarms
  • Twilight settings: So that the motion detector also “knows” when it is night and when it is day and when it is daytime, you can make twilight settings. Then the device recognizes when twilight sets in and does not consume power unnecessarily during the day
  • Lighting duration: The duration of the lighting ranges from a few seconds up to 30 minutes. It’s not quite clear which of these is useful. A light that is always activated light may be more noticeable than a 30-minute illumination. How burglars and when they flee is unclear
  • Installation: Of course, the settings only bring something if you have bought a good Device and have installed it correctly (see above) – in terms of angle, concealing the angle, concealing furniture, etc
  • Care: Especially with motion detectors for the garden and balcony you should clean the lens from time to time and remove spider webs. Also with motion detectors for indoors you should also dust them from time to time


Update: 2023-01-20 / Affiliate Links / Bilder von der Amazon Product Advertising API