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Decent Motion Sensing Lights?
Above asks: "At my previous house I purchased a number of motion sensor lights to replace the standard flood lights. I simply went to the nearest Home Depot and bought a mid range model, and they worked great. Since then I've moved, and in the new house I did the same, and got some Heath-Zenith units from Home Depot. They were junk (came on all the time for no reason). I adjusted two different units to no end, they simply didn't work. Since that was basically all Home Depot carried, I went to Lowes, and got a Regent Lighting unit. It was better, but not by much. I want my back yard to be relatively sensitive, triggered by the dogs when we let them out, but the front yard to be insensitive, triggered only by a car or the close approach of a person. Where can I get a good quality, motion sensor flood light? What are the secrets to aiming and adjusting them so they work right?"
I'll make this brief. A company called X10 (specifically here) has everything you need. Good quality stuff at reasonably affordable prices. Browse the site, you'll like what you find.
Honestly, they are just lights. If you are letting the dogs out, just flip the switch. Nuff said.
I mean srsly
What do you expect?
The best of ask Norm:
http://www.amazon.com/This-Old-House-Best-Norm/dp
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I have the same, cheap, [brand of] Heath-Zenith lights and they work fine. I suspect that the environment that your lights are set within are the problem. If you have trees with branches in sight of the passive system, the wind will blow and set off the lights. That may be the only difference between houses: environmental variation. I have noticed that they are more sensitive in colder months than warmer months. This may be the temperature interacting with the sensors, or it could be other changes to the environment. I have not tried to systematically tease these things apart.
Pitfalls and caged tigers (claymores if you can get a few. REALLY easy to use. "FRONT: This side towards enemy")
But seriously, flood lights aren't going protect your home very well, especially DYI projects. If it's safety you have in mind, it is worthwhile to call the professionals.
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Remember who paid for all those annoying pop-up and pop-under ads when they first came out? X10 are the primary reason all browsers come with popup blockers these days. Their internet marketing tactics stink.
I won't support them. And I urge others to do the same.
the growth in cynicism and rebellion has not been without cause
Most of the sensors have a plastic "light guide" in front of them that breaks the sensed area into zones. It is the changing difference between the zones that triggers the sensor. Try taking one of them apart and you'll see either variations in the lens plastic, or even a set of physical baffles between the outer filter and the sensor itself.
(You can actually walk by most IR sensors without setting them off if you move VERY slowly, which is why better quality alarm systems use radar or specific thermal level monitoring rather than just a change).
Which brings us to aiming. Most of the time the zones are arranged to be more sensitive to side-to-side motion than up/down. So if you have one oriented 90deg out of "true" then it'll be rather insensitive except in a narrow band. (This is a good way to limit the area of coverage of a sensor without having to break out the masking tape).
Speaking of which, the height and angle of the sensor makes a big difference for the same reason.
So I would recommend taking one apart, figuring out the zone layout and adjusting accordingly. (Heck, you can even just set one on a table and see what area it "sees" and how sensitive it is to motion in that area, then turn it 90deg and try again).
Dear Slashdot,
Once again I awoke this morning hungry. I installed food into my mouth yesterday when I woke up hungry too. In fact, I installed food three times yesterday. And they day before that. And the day before that. This seems like such a cheap hack to a simple problem. Is there any way I can automate a solution to this problem? I have a few requirements though. Of course it must be open source and patent free. Also, I would prefer a linux based solution. Any suggestions would be great!
I researched the X10 stuff and bought three floodcams, extra receivers, a RF/powerline transciever, and USB RF receiver and control interfaces for a computer for about US$430.
For the money spent, it was a good deal: the cameras, though poor quality work, and the flood lights come on when sensing motion, sending X10 events and responding to X10 commands to turn on the cameras and floodlight.
However:
1) The video range is poor. Figure 20 feet max through typical household construction, and interference can be significant.
2) The motion sensors are not particularly responsive. The floodcams have the option to gate the lights based on the motion sensors and it being dark (i.e. at night), but those motion sensors are fairly insensitive, and worse, it appears that the turn off delay does not work if the light sensor detects light after the motion sensor turns the light on -- if the light reflects of a shiny object -- we have trouble with one car in our driveway if it is parked too close.
Still, being able to control the floodlights with a handheld remote or a computer is, by itself, a nice plus. The (admitedly poor quality) cams are a bit of a perk, but I wouldn't rely on them for serious surveillance (a good stationary camera will run $250 to $500 alone -- closer to $1000 when you start talking about good PTZ units).
Of course, compare this to close to $200 for a decent motion / time of day sensing light alone which I used to have.
Granted the X10 ads are annoying and I've let them know, several times, that their practices reflect badly on their products which are otherwise fair value for the money. I suppose that they remain effective, though.
You could've hired me.
How do you tell Decent Motion from Indecent Motion?
Yeah yeah, "I'll know it when I see it".
I've seen motion detector lights come on when a radio transmitter fired up nearby.
Also, poke around: some have sensitivity adjustments.
Go really hardcore and wire them into your home security system. Passive infrared detectors for alarms systems are high quality and a reasonably sophisticated panel can be programmed to turn lights on without sounding an alarm.
First off, I have to say I agree with the original poster... I too tried to use the Zenith stuff from Home Depot when replacing lights for a friend and the stuff simply doesn't work. Pretty disappointing since there isn't much to this stuff. When I started looking into doing lights for my home I also looked at the X10 stuff but finally decided to build my own infrastructure. Not that there is anything wrong with the X10 stuff... it's affordable, easy to use, and has lots of software support. However, I'm building some custom home automation stuff anyways (such as asterisk integration and a cross platform graphical data-flow language for microcontrollers so you can embed control logic onto a cheap controller board instead of using a dedicated pc without needing to know how to write code) so I figured I'd customize the motion stuff as well. I found some GE motion sensors for about $10 that work great (and actually come with docs covering sensetivity, range, effective angles, etc... which you don't normally get in a packaged unit). I modified them a bit to add tamper detection but otherwise they work great out of the box. These feed back into a controller board which can also control the flood lights (which are just standard floods controlled by relays). And yes, I'm sure all this can be done with X10, I just prefer to build my own stuff (http://www.kondra.com/circuit/circuit.html).
I recommend trying out the space pen. Containing a pressurised ink cartridge, it'll write reliably at any angle, on just about any surface. These pens were used by NASA in space, for their ability to work in zero gravity. Plus, you'll get geek cred for owning one.
I've always been a big fan of the reverse-motion sensor light... I think it's much more useful to have them turn off when they see motion than turn on.
eom
Try the motion sensing lights from Costco/Price Club.
"... flood lights aren't going protect your home very well..."
Motion sensing flood lights are VERY annoying to someone trying to sneak around. Annoying enough that they may consider trying another house that doesn't have motion sensing lights.
Please don't comment on stories in which you have no interest.
Also: Use a power line filter to prevent the lights from being triggered by power line spikes.
--
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The point is /. is a poor place to ask these kinds of questions. They'd do much better asking a home improvement forum, rather than a bunch of computer nerds.
Please don't comment on posts in which you have no interest.
You see what I did there? He DOES have an interest in it. He has an interest in stopping future stories like it that also have absolutely nothing to do with Slashdot. Just the same as you had an interest in stopping him from posting about them.
"If you make people think they're thinking, they'll love you; But if you really make them think, they'll hate you." - DM
Most of the sensors have a plastic "light guide" in front of them that breaks the sensed area into zones.
Its not a light guide its a plastic fresnel lens with multiple elements which focuses light (actually heat) from various "zones" onto the sensor.
It is the changing difference between the zones that triggers the sensor.
Nope. The sensor is made from two seperate pyroelectric elements which are mounted side by side. It is differences between these two elements which triggers the device. This could be from the same zone or different zones. Sun light and other ambient light (heat) changes will affect both elements equally (you hope) so that they don't trigger the device.
Try taking one of them apart and you'll see either variations in the lens plastic, or even a set of physical baffles between the outer filter and the sensor itself.
(You can actually walk by most IR sensors without setting them off if you move VERY slowly, which is why better quality alarm systems use radar or specific thermal level monitoring rather than just a change).
Which brings us to aiming. Most of the time the zones are arranged to be more sensitive to side-to-side motion than up/down.
The are all like this due to them being two element devices.
So if you have one oriented 90deg out of "true" then it'll be rather insensitive except in a narrow band. (This is a good way to limit the area of coverage of a sensor without having to break out the masking tape).
True.
Speaking of which, the height and angle of the sensor makes a big difference for the same reason.
So I would recommend taking one apart, figuring out the zone layout and adjusting accordingly. (Heck, you can even just set one on a table and see what area it "sees" and how sensitive it is to motion in that area, then turn it 90deg and try again).
The biggest difference between the systems you can buy is the shape of the fresnel lens. You can have just one main zone or lots of sub zones or a combination of both. Most good systems will give you a diagram of the size and position of the zones which you can use to choose and position them.
wot no sig
I ended up giving up on backyard astronomy because I kept trigger neigbors' security lights. Nothing like spending half an hour getting dark adapted and being hit in the face with a pair of 150 watt spot lights.
One of my neighbors has a burglar alarm which he only sets when he goes on vacation. It has internal motion sensors that are triggered if a passing wind rattles one of his windows. This means we are treated to a 120db external siren on almost a daily basis.
Blackouts are an inconvenience, but we used to make them fun by lighting a fire in the fireplace, cooking over a camp stove, and lighthing candles and lanterns and maybe reading stories to the kids. But a couple of years a go a vogue went around the neighborhood for buying gasoline powered emergency generators. Since noise from these things apparently isn't regulated, lamplight reading is out because the neighborhood sounds like a motor speedway.
I'm all for collecting geeky stuff, but it's one thing to have an attic electronics lab, it's another to deny a neighbor the right to be in his back yard in the dark. There's a growing and unhealthy obsession with extending and expanding our personal space, whether it's building houses as close to the property line as allowed, shining lights into neighbors' yards and windows, or driving an absurdly large SUV.
The Stoic philosophers reasoned this way about happiness: if happiness is having all your wnats satisfied, the surest way to happiness is to self-regulate your wants. Epictetus once told the story of placing an iron lamp on the outside of his house; he heard an odd noise outside his door he went out to find that a thief had stolen the lamp. "Tommorow, my friend," said Epictetus, "you will find a clay lamp; a man can only lose what he has."
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Yes. Because a fucking carpenter would be a genius when it comes to lighting.
Free clue: If it isn't wood or a fancy power tool, Norm doesn't know.
Well, myself I think that the answers were quite interesting. I'm thinking about the thread on dissassembling the lights, and the debate about how they work. This is true nerd thinking...
:)
Of course, the original question looked more like "what brand should I buy", which is _not_ nerdy.
How to DIY is the way to go..
I'll say this: properly adjusted motion-sensor lights should be mandatory. Light pollution sucks, and is wasteful.
Your comment is inherently redundant.
nothing
And if you haven't read Epictetus' Manual, you should. It's a short, intriguing read. Try Lebell's plain English version. (Epictetus was a Stoic philosopher.) http://www.powells.com/biblio/1-0062511114-0
"Not an actor, but he plays one on TV."
The company that is responsiable for those pop-ups is out of busniess.
o gy
http://en.wikipedia.org/wiki/X10_Wireless_Technol
You're new here, aren't you?
Kid-proof tablet..
I had the same issues Home Depot & Lowes both stock crap. Go to an electrical supply house and get RAB lights. They simply work. http://www.rabweb.com/product_line_detail.php?prod line=STL360
I'm extremely please with the results.
I'm not associated with RAB, etc.
Steve
Regards, Steve
http://www.sensorsmag.com/ is often a good starting point for sources of this type of technology.
Some manufactures of modules are http://www.napion.com/ and http://irtec.com/ . MuRata makes the IRA-E700, Global makes the RE200B and good ol' Hotek makes a controller for the sensors, HT761X.
Here is the NEMA spec for motion sensing http://www.nema.org/stds/wd7.cfm
"Do Yourself In"?
They'd do much better asking a home improvement forum, rather than a bunch of computer nerds.
Slashdot seems like a decent place to ask questions about home automation-related projects. The submitter is asking about something fairly basic, but it's still part of a wired-up home.
"...always new atoms but always doing the same dance, remembering what the dance was yesterday." -Richard Feynman
I know this is a little bit off subject, but in the interest of DIY you could build your own. I've been using Sharp's OEM IR sensors to good effect in my indoor lighting projects. They're basically a frequency modulated IR beam emitted from the sensor, coupled with an IR sensor configured to detect only the frequency of the emitter. The devices output a voltage which is proportional to the distance detected. If you know how to program a microcontroller, you could program your own object detection algorithm which would likely trump most of the commercial devices out there.
a rp/sharp.html
Anyway, my two cents. I'm using the shorter range versions of the sensor for my lighting design (http://www.designeb.com/).
More information on the Sharp distance sensors can be found here:
http://www.acroname.com/robotics/info/articles/sh