Motion Sensor Light Switch – What you need to know

A Motion Sensor Light Switch is often also referred to as “Occupancy Light Switch” as well as “Vacancy Light Switch”. But there is a difference between the two.

An Occupancy Light Switch automatically turns on the lights as soon as motion is detected in the sensor range and automatically turns the lights off when the motion is no longer detected in the range .

With a Vacancy Light Switch you still need to manually turn on the lights but the switch will take care of turning the lights off when the motion sensor no longer detects any activity.

Lutron and Leviton are renowned companies that are specialized in the area of occupancy and vacancy sensors in combination with light switches. The Lutron Maestro is basically the flagship of motion sensor light switches. But also Belkin’s WeMo portfolio now contains smart motion sensor switches to control lighting.

Around this technology there even is new market evolving under the term “Smart Lighting” which refers to energy efficient and automated lighting systems. These systems should manage their own power cycles based on conditions like daylight times or occupancy. Not to mention the usual capabilities like programmable schedules, remote web interfaces or even smartphone apps.

Things you need to know

  • Almost all Motion Sensor Light Switches require to be grounded (this is the third wire besides the Black and White one). The reason for this is that most dimmers,timers and motion sensor switches require power to operate. Very often a neutral wire is not present in a switch which is why the clever engineers found a way to power the device via the ground conductor.
  • You can precisely adjust the timing and sensitivity of these switches. So don’t worry about sitting in the bathroom while the lights go out. Although you can find similiar stories on the Internet it is often just a matter of the right installation. A good home automation system takes time and patience.

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  1. If your bathroom light switch faces the wall you may be waving your arms to reactivate. Microwave sensors “see” through walls so you’ll have lights turning on when not needed. If you are building a new home, skip the aftermarket products and consider a purpose-built system for lighting control. DC lighting and control systems are simple and reliable and don’t need any advanced iPhone controls to turn the lights on. Just a plain old switch or occupancy sensor like you described in this article. However, with many of these systems you can also add sensors anywhere including the lights themselves. Check out LumenCache for example.

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