What is this white contraption attached to the wall?

Question

My dad's staying at a hotel in the US, and forwarded me the picture beneath. What is it?

I'm voting to close this question as off-topic – Giorgio Jul 26 '18 at 12:10 — Giorgio, Jul 26 '18 at 12:10

score 29 · Accepted Answer · edited Jul 26 '18 at 00:53

29

It will switch the light on when it sees movement in the room.
There is an explicit touch-switch in the lower area, if you tap it, it toggles the light on/off.

edited Jul 26 '18 at 00:53

Greg Hewgill

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answered Jul 26 '18 at 00:49

Aganju

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They are mostly used to reduce air conditioning/heating when the room is vacant. – user71659 Jul 26 '18 at 01:35
It's full of these in Romania in many public institutions. – StefanS Jul 26 '18 at 09:08
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@StefanS - I'd say these are common worldwide! – Conrad Jul 26 '18 at 09:46
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I normally see these as part of a burglar alarm system. – AndyT Jul 26 '18 at 10:10
Thanks. (1) My dad couldn't feel the switch? (2) Is this sensor battery-operated? How'd it work without power? – Jul 27 '18 at 01:06
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(1) there is no mechanical switch. You need tap it once quickly. (2) it's connected to the power in the back. Note that it could be broken. – Aganju Jul 27 '18 at 03:46
They're also called PIR sensors (Passive Infra-Red) – CSM Jul 28 '18 at 12:54

What is this white contraption attached to the wall?

1 Answers1