Best motion sensor? (UK)

As titled. What’s the ST compatible motion sensor available in the UK right now?


for me it’s the fibaro motion sensors. Watch out for regular sales of these on amazon where they consistently are sold for as low as £35 each

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I’m using the Samsung one you get for £29 at curry’s. Works brilliantly, is very small & discreet.

I’m using two ST ones bought from currys and having no issues todate with them. Battery power dropped to 88% very quickly ie within a few days which had me worried but has stayed there ever since about 4 months now.

So all good with the ST sensors for I guess simple motion sensor configurations.

Tier reporting. The 88% just means “less than 100%.”


Tks JD for that info

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I’ve bought a shedload of Samsung ST ones and have really regretted it. Personally I don’t think they are fit for purpose. Constantly randomly alerted to false alarms on at least one of the 30 I own when I’m not in.
ST advertise you knowing if someone is at home home when you’re not by using smartthings. Well actually you never do know for certain because you can never be sure if it’s a false alarm or not.
Apart from relying them for turning on lights I would not trust them for anything else. I’m pleased I haven’t installed a siren, otherwise the neighbours would hate me by now.
The fibaro ones I bought are much more reliable.

Same here, false alarms from the ST ones but not from the Fibaro’s! I do find the Fibaro motion sensors slightly slower though to detect motion.

My Aeon Multisensor 6 has been pretty bulletproof. Always detects motion quickly and no false alarms.

I’m hoping smartthings are able to update the firmware on these in future and fix this. I was on the other side of the country a few days back and had a succession of 5 different motion sensors trigger. All of them Samsung ones. The fibaro ones were solid. However they are as you quite correctly said, slower to trigger lights.

Thanks, all.

When you say the Fibaros are slower to detect motion / turn on lights; how slow are we talking? Like a fraction of a second or a couple of seconds?

Must admit I haven’t noticed any real difference between the ST or the Fibaro sensors.
What I will say is that the Fibaro include a Lux sensor which I find extremely useful for my lighting automation.

My own experience is that the fibaros take about 1 or 2 seconds to light up the room. The ST devices are lightning fast. However the fibaros do not seem susceptible to false alarms and also have the useful lux sensor and an led flash to indicate Motion which I like.

This fibaros use Z wave and the smartthings branded sensors are zigbee. So speed would depend in part on what we call “the strength of the mesh” for each protocol. Basically this means the number of wired devices you have for that protocol and how they are laid out through the house.

Ideally, you would have two mains-powered devices of each protocol about every 15 m. Of course that’s a lot of devices, and not everyone wants to spend that much money.

Z wave plus has the longest range, significantly longer then Zigbee. But classic Z wave is only a little bit better than zigbee.

However, zwave is limited to 4 hops total for one message while zigbee can have up to 30 (15 in to the hub and 15 out) so zigbee may be better if you need to get around a lot of architectural obstacles, such as in a Brick house.

Anyway, the minimum you will need is one mains-powered device about every 18 m, although if you have brick walls it may need to be every 10 to 12 m as brick is harder to get signal through.

The point of all this is that while adding more devices to a Wi-Fi network would generally make each device communicate more slowly, adding more mains-powered devices to either Z wave or zigbee will usually means that each device will communicate more quickly.

Consequently, I can set up a House with SmartThings so that Z wave runs fast and the zigbee runs slow, or vice a versa. Or so that both run fast or both run slow. It’s all about the strength of the mesh.

So that’s why some people will say the SmartThings sensor is very fast and other people say it’s very slow. If you put it just at the edge of the range for zigbee and don’t have any repeating devices, it’s going to be slow. But if you have a zigbee repeater like the SmartThings pocket socket every 15 m or so it’s going to run much more quickly.

Z wave can repeat only for Z wave. Zigbee can repeat only for Zigbee.

Repeaters are mains-powered devices, typically inwall relays, pocket sockets, and plug-in sensors. Battery powered devices do not repeat.

So when looking at battery-powered sensors, the first question is what specific devices will you use to repeat the signal? Usually lighting is your primary source of mains-powered devices. If all your lighting is using Z wave relays, I would recommend getting zwave sensors like the Fibaro or Aeon. But if you have a Zigbee pocket socket in every room, the zigbee sensors should communicate very quickly. :sunglasses:



Very useful write up. My problem is that my Fibaro Motion Sensor ZW5 works fine when the Motion Sensor is sitting on top of my Smartthings Hub, but not when it is in another room about 5 meters from the Hub.

I have a house full of Fibaro Dimmer 2s (About 25 at the moment) so I would have thought my z-wave mesh was good too. The lights work flawlessly.

Could it just be that I was unlucky and have a particularly bad Fibaro Motion Sensor, and should try another?

I’d get a z-wave repeater to plug into the wall, but not sure this was intended to bridge a 5 meter distance!?

Any help appreciated…


When did you last run the Z wave repair utility, and did you get any error messages? ( make sure you first place the motion sensor in the location where you want to use it)

Thanks. I tried a few z-wave repairs and waited 15 minutes or so. Got a few error messages relating to Device IDs no longer on my network saying they couldn’t join the mesh, which seemed obvious (as they don’t exist) and strange.

Still, after the repairs the Fibaro Motion Sensor was only able to be included when placed on top of the Smartthings Hub, and then only Synch when within a meter of the Hub.

When you say make sure you first place the Motion Sensor in the position you want to use it, I guess this is tough if I can’t get it to include from that distance from the hub.

Out of interest, do you own a Fibaro Motion Sensor and, if so, do yours work when placed more than a few meters from the Hub?

thanks again!

I have 4 Fibaro Motion Sensors and don’t have any issues with them.
I have 2 old versions (2.04) and 2 new (3.2).
My hub is in a spare bedroom and I tend to pair them in the lounge downstairs.
Never have any issues.

Thanks. I am going to try and take the Hub into the room where I plan to place the Fibaro Sensor and include and Synch in that room. Then move the hub back to its normal spot in a room about 7 meters away.

I have 4 groupings of about 5 Fibaro Dimmers each located throughout the house and I wonder whether the Motion sensors signal is getting lost amongst them and not making it back to the hub!?

It’s a long shot but not sure what else to do!

Was your pairing and synching straight forward?

No problems at all.
I have just followed the manufacturers instructions.
Put hub into Z-Wave exclusion and press button 3 times.
Press find a thing, press button 3 times.