The Brinks Plug-In Motion Sensing Timer has a motion sensing alarm and is easy to use.
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Questions & Answers for Generic Brinks Plug-In Motion Sensing Timer
The Brinks Plug-in Motion Sensing Timer Model 44-2030-2. Is this an alarm that could protect a window from being open?
asked 2 years, 3 months ago
on Brinks Plug-In Motion Sensing Timer
This is not an alarm system or sensor. It is simply a switch that turns on a light or other item plugged into it when it detects motion.
You could use it for this purpose, but only to the degree that a) you have an electrical outlet to plug this device into where it has a clear line of sight to the window, and b) you plug some AC powered device -- a lamp, or something that creates noise such as a radio -- into this unit. It should then detect the motion of anyone entering by means of the window (but only after they were inside) and turn on the light or the noisemaking item (e.g. a radio).
Note that you would need to adjust the "Light" control properly also if you want the sensor to be active during the day (for most purposes, it is adjusted so daylight prevents the switch from turning on).