FAQ: Where to locate motion sensor for fastest response?

What about a ceiling version mounted overhead? That’s often a good way to get a crosswise angle of incidence, but you need one with a wide field, which is why it’s better to choose a device designed for a ceiling mount. But you can try it with any motion sensor it’s just a question of where the field catches you. If you want to catch someone coming out of a bedroom into a hallway, a ceiling mount sensor will often work fine.

Also, you can see this in the first graphic I posted upthread, but I didn’t call out specifically that the detection field widens with distance. This can be a help for a ceiling mount, that extra foot or two of distance gives you wider coverage below. Sometimes you just need to experiment to find the best placement.

The MOT is the first generation and does not work with SmartThings.

With Iris zigbee devices, you want the ones that are in the purple boxes (not the clear clamshells) and where the user guide specifies “zigbee home automation 1.2” which is the same profile that SmartThings uses. If it just says “zigbee” it might use a different profile and not be compatible.

These are sometimes called Iris first generation (zigbeedevice is not compatible with smartthings) and Iris second generation, but the boxes aren’t labeled that way.

The Iris Z wave devices mostly all work with SmartThings regardless of first or second generation. The issue only comes up with the Zigbee ones.

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I really like the iris sensors due to their speed. But their small size is great!

My master bedroom is at the end of a25 ft hallway. Right out side the door is the overhead light fixture for the hall. I have one of the sensors mounted announce the door facing the light fixture. You can’t even tell it’s there.

As I walk down the hall the light fixture blocks the sensor until I am about six feet from the door. So as I walk the last six feet the lights are fading up to the mode level and are at the proper level just as I walk through the door.

I have these all over the house in spots and they are barely noticeable.

That’s because they are zwave. I am yet to find a zwave sensor that reacts faster with SmartThings. I don’t know if it’s a SmartThings limitation or zwave protocol, but no matter what Zigbee sensors I use they react a lot faster than any Aeon, Fibaro or Ecolink sensors. I am now a fan of NYCE sensors. They seem very responsive for cloud and local applications.

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I agree, zigbee seems to respond much faster.

I was looking at the NYCE ceiling mount motions. Wonder how they would actually look on the ceiling. I don’t want to cut holes in my walls, considering in a few years tech changes.

It’s a light sensor. I used double sided tape with mine.

I have monoprice, gocontrol, and smathings sensors.
Both the monoprice and gocontrol are zwave and are very slow worthless for turning on lights.
The smartthings is zigbee and works very well for motion and temp but also cost twice as much.

Dose anyone know of a good outdoor motion sensor.
I have been looking at the aeon labs MultiSensor 6 but it has several bad reviews and i am afraid that it will also be very slow?

Please see the outdoor motion sensor FAQ. It should help answer your question and you can ask any follow ups there. I don’t want this thread to go off topic. :sunglasses:

Picked up an Iris Motion Sensor today and used it to replace the Ecolink in the hallway. I agree that the Iris responds much faster. I was able to put it in one of my original locations - above one of the two doors at the ends of the hallway - and entering from each direction triggered the light within a couple steps, which is plenty good for me. Thanks for everyone’s help! I’ll probably get two more Iris to replace the ones I have at the top and bottom of the stairway now, but that won’t be for a while.

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Where can I get the iris sensors in Canada? I can’t seem to find any place to purchase that will ship to Canada.

Also, I am wondering how well the battery lasts in the Iris motion sensors?

Iris is a Lowe’s house brand–they can only be purchased new at Lowe’s. Or occasionally at Amazon.

There is one listed on https://www.amazon.ca/Iris-3326-L1-Motion-Sensor/dp/B01GCKAF6K/ref=sr_1_1?ie=UTF8&qid=1472484430&sr=8-1&keywords=iris+motion+sensor but it appears to be a single unit and there are no other listings. You might consider contacting the seller to see if they have or can get more than one.

Interesting that www.lowes.ca doesn’t have any Iris products.

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I saw that one also but it seems kind of suspicious that he only has 1.

Probably just an end-user selling the one he has. Anyone can sell on Amazon similar to Ebay. I’ve sold things myself that way on Amazon. Interestingly, it’s shipping from the US.

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Hi all-

Isn’t there one other factor at play here, which is whether the sensing and action are being processed locally in the hub (V2) vs going to the cloud? As I understand, there are currently a small number of devices that ST supports for in-hub processing. If you are using motion sensors and switches that are on the short-list, I would expect the response to be almost instant vs those routed to the cloud.

We can hope so. :sunglasses:

That said, since local processing was first made available with the V2 there have been reports on and off from different community members that sometimes the locally operating devices have more lag than the ones that go to the cloud. In any case, you can certainly try it and see.

That said, the positioning guidelines still apply. A PIR motion sensor that you walk towards will take longer to respond than the same one positioned so that you walk across the field of detection. The intent of this FAQ was to discuss positioning of a specific sensor, not compare one to another. Many people are unaware of how the PIR sensors work, and think of them as detecting the way a person’s vision would, so they place the sensor in exactly the wrong place in terms of detection speed: so that you walk straight towards it.

All that said, I am about to remove my Iris motion sensors due to battery drain. If Ecolink’s due last 2 years, Iris sensors are genuinely the worst buy. I have many Iris sensors, and there’s no way they last for more than several months on a fresh battery.

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Wow really? My iris sensors are going strong on the original batteries… I’ve had them installed for at least 6-9 months… However long ago it wss that the gen 2 iris sensors came out.

But, if you don’t want them… Let’s make a deal! I’m buying!

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I think I just got a really bad batch. I’ve had to return around 40% of them.

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