# Our Mysterious Motion Sensor **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [March 8, 2023, 1:11pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873 "2023-03-08T13:11:12Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [March 9, 2023, 11:13am UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/41 "2023-03-09T11:13:08Z")
The obsession over “turning off lights” has always been a bit mindboggling to me. Because energy “wasted” on leaving a light on doesn’t amount to much in the big scheme of things. Many decades ago, someone at my workplace had a bright idea (no pun intended). Each light fixture in the hallway contained four, 48 inch fluorescent bulbs, and he proposed to remove two bulbs from each fixture as an energy-savings initiative. It was done, and he got a reward for it. Many months later someone did an analysis on the monthly electric bills: _there was no measurable difference in energy usage_. The bulbs were eventually replaced. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 9, 2023, 12:05pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/42 "2023-03-09T12:05:18Z")
Wow, I have no complaints whatsoever compared to that! ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 9, 2023, 12:06pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/43 "2023-03-09T12:06:52Z")
> [@Musicat](#): > > Why not just replace the sensor with a light switch? Let’s not cloud the issue with logic or common sense! LOL I’m afraid I’m in the same boat as Machine\_Elf on that one. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 9, 2023, 12:43pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/44 "2023-03-09T12:43:25Z")
> [@Jasmine](#): > > > [@Gorsnak](#): > > > > Never heard of a mic for an occupancy sensor. The other thing you could try is to make the motion of clapping your hands but “miss” by passing your hands in front/behind each other. I suspect that the motion you’re generating by clapping has a slightly different profile than just waving, possibly faster and more abrupt, and that difference is what trips the sensor. > > That is a good idea! I’ll try that tomorrow morning! Well, I tried it, and the clapping motion had no effect! It only works when I use the exact same motion and make the loud clapping noise! So, the only conclusion I can reach is that it must have a mic. Oh, well, my tube guy has been shipped! ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [March 9, 2023, 1:02pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/45 "2023-03-09T13:02:07Z")
> [@Crafter\_Man](#): > > The obsession over “turning off lights” has always been a bit mindboggling to me. Because energy “wasted” on leaving a light on doesn’t amount to much in the big scheme of things. I don’t know about this. When I moved in with my gf she suggested we look at the electric bill for the first few months to see how much it went up. She is extremely bad about leaving lights on, I’m the extreme opposite. Our electric bill went down a few dollars a month after I moved in. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 9, 2023, 1:05pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/46 "2023-03-09T13:05:31Z")
> [@Crafter\_Man](#): > > The obsession over “turning off lights” has always been a bit mindboggling to me. Because energy “wasted” on leaving a light on doesn’t amount to much in the big scheme of things. In our case, you are absolutely right because we have a modern LED lighting system that uses WAY less energy than our old fluorescent system, and they are actually brighter. ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [March 9, 2023, 4:26pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/47 "2023-03-09T16:26:48Z")
> [@Machine\_Elf](#): > > … I don’t have the authority to replace the sensor in my office. A lot of times, especially early in the morning before anyone else arrives, the weirdest unexplainable stuff happens and, since it benefits everyone in the office, no one thinks to report it. ---
**Author:** ![Topologist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/topologist/32/3208_2.png) [@Topologist](https://boards.straightdope.com/u/Topologist)\ **Post date:** [March 9, 2023, 6:14pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/48 "2023-03-09T18:14:58Z")
> [@Musicat](#): > > Why not just replace the sensor with a light switch? One of the advantages of academia is that faculty get private offices. I moved into a new office not long ago, which had one of those sensors in place of a light switch. Besides the fact that it turned the lights off while I was quietly sitting at my desk working, it was a pain to turn back on because a section of the hutch on my desk blocked it from direct view (me of it or it of me). I happen to be friendly with the fire safety officer, and mentioned it to him when he was inspecting offices. (Some people keep way too much paper piled up in theirs.) He gave it a nudge with his elbow and said, “Look at that, it’s broken. I’ll have it replaced.” Came back after the weekend and there was a proper switch in its place. It helps to have friends in the right places. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 9, 2023, 6:16pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/49 "2023-03-09T18:16:02Z")
> [@jnglmassiv](#): > > A lot of times, especially early in the morning before anyone else arrives, the weirdest unexplainable stuff happens and, since it benefits everyone in the office, no one thinks to report it. Anything happening at work that actually benefits everyone in the office truly is “weird and unexplainable”. LOL ---
**Author:** ![Zyada](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zyada/32/3028_2.png) [@Zyada](https://boards.straightdope.com/u/Zyada)\ **Post date:** [March 10, 2023, 4:12am UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/50 "2023-03-10T04:12:22Z")
I’ll be interested to see if the wavy guy actually works. It’s definitely an infrared sensor, so it shouldn’t make a difference unless he’s pretty warm. I was in a store once when a really strong cold cold front was coming in. The automatic doors were opening and closing as waves of cold air hit the sensor range. ---
**Author:** ![DesertDog](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/desertdog/32/11503_2.png) [@DesertDog](https://boards.straightdope.com/u/DesertDog)\ **Post date:** [March 10, 2023, 5:01am UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/51 "2023-03-10T05:01:19Z")
> [@DavidNRockies](#): > > So … Peekaboo, then. They’re learning Object Permanence. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [March 10, 2023, 11:48am UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/52 "2023-03-10T11:48:30Z")
> [@Crafter\_Man](#): > > The obsession over “turning off lights” has always been a bit mindboggling to me. Because energy “wasted” on leaving a light on doesn’t amount to much in the big scheme of things. > > Many decades ago, someone at my workplace had a bright idea (no pun intended). Each light fixture in the hallway contained four, 48 inch fluorescent bulbs, and he proposed to remove two bulbs from each fixture as an energy-savings initiative. It was done, and he got a reward for it. Many months later someone did an analysis on the monthly electric bills: _there was no measurable difference in energy usage_. The bulbs were eventually replaced. By “no measurable difference”, I’m guessing that the monthly variability in the electricity usage made it hard to spot the real reduction in electricity usage just for lighting. which must mean there were a lot of other things contributing to the bill, e.g. industrial equipment, or just a lot of other lighting in the workplace that _didn’t_ get halved like the hallway light. If my office has ~100 watts of LED lighting and it’s perpetually on, that’s about 36 cents a day (figure 15 cents per kilowatt-hour). For a company with 350 employees, that’s $126 a day, $3780 a month, $45,360 a year, just for lighting. Motion sensors ensure that those lights get shut off after hours and on weekends and holidays, and further trimming is possible by ensuring the lights go out when a monitored space is unoccupied for more than ten minutes, e.g. when someone is in a meeting room or out for lunch. It’s just unfortunate that in some cases the motion-sensing lights cause inconvenience for folks like me and @Jasmine; I wish the bureaucracy were a bit more flexible in special cases like that, e.g. by allowing the timer to be extended beyond ten minutes, or by locating the motion sensor in a place (e.g. the ceiling) where it’s better able to see the occupants of the room. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 10, 2023, 12:08pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/53 "2023-03-10T12:08:04Z")
DRUM ROLL … Tube Guy is here! He is undulating in the corner in plain “sight” of the sensor. We shall see … ---
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [March 10, 2023, 1:07pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/54 "2023-03-10T13:07:25Z")
… And? ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 10, 2023, 1:12pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/55 "2023-03-10T13:12:22Z")
Eighty consecutive minutes without the lights going out! 😃 ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [March 10, 2023, 1:45pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/56 "2023-03-10T13:45:04Z")
> [@Gorsnak](#): > > Never heard of a mic for an occupancy sensor. Me neither, but this thread inspired me to look around, and yep, they’re out there. Right now my garage’s nice bright main lights are wired to come on when the garage door goes up/down (or when I push the light button on the wall-mounted garage door opener), but the things I did to make that happen probably aren’t code-legal. Now I want to get a couple of these: > **[Lithonia Lighting Contractor Select CMR Series 360° Small Motion Dual...](https://www.homedepot.com/p/Lithonia-Lighting-Contractor-Select-CMR-Series-360-Small-Motion-Dual-Technology-Standard-Range-Ceiling-Mount-Occupancy-Sensor-CMR-PDT-9/204806452)** > > Maximize your energy-savings while reducing maintenance costs when you automate the ON/OFF switching of your light fixtures. The Sensor 360° Low-Voltage Ceiling-Mount Occupancy and Motion Sensor with Dual Technology incorporate Passive Infrared (PIR)... They can be wired in parallel, so one sensor on each side of the garage should give good coverage, not just for detecting arrival/departure of cars, but people too. They are passive-IR triggered, but include mics to listen for continued occupancy - so if I’m under the car changing oil or something, and the lights time out, I can yell “GODDAMIT” and get the lights to come back on. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [March 10, 2023, 1:46pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/57 "2023-03-10T13:46:44Z")
Looks good! It’s also safer because, personally, when the garage door goes up, I want it lit so I can be sure no one is in there. ---
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [March 10, 2023, 2:45pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/58 "2023-03-10T14:45:12Z")
> [@Jasmine](#): > > Eighty consecutive minutes without the lights going out! Hey, cool, how about that! ---
**Author:** ![pjd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pjd/32/3009_2.png) [@pjd](https://boards.straightdope.com/u/pjd)\ **Post date:** [March 10, 2023, 3:00pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/59 "2023-03-10T15:00:42Z")
How much power does tube guy consume ? I couldn’t get the info from the amazon link (other than “about as much as a small fan”) ---
**Author:** ![Buck\_Godot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/buck_godot/32/6573_2.png) [@Buck\_Godot](https://boards.straightdope.com/u/Buck_Godot)\ **Post date:** [March 10, 2023, 3:15pm UTC](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873/60 "2023-03-10T15:15:08Z")
To the OP: Are you sure that you and your thee coworkers weren’t killed in gas leak several weeks ago, but haven’t moved on to the next world because because you fell you have “unfinished buisiness” in the office? Just saying its a possibility. If you see a big light and a voice tells you to go towards it, I say go for it. [Previous page](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873.md?page=2) [Next page](https://boards.straightdope.com/t/our-mysterious-motion-sensor/980873.md?page=4)