UNRELIABLE! Motion Sensor often miss turning light ON/OFF

Hi i have recently just set up my entire house with various z-wave smart devices.

Currently have:
1 Smartthings V3 Hub
45 GE z-wave switch/dimmer
12 Zooz ZSE18 motion sensor
2 Zooz ZSE40 motion sensor
2 Zooz ZEN15 Power Switch
1 Smartthings motion sensor
1 Smartthings multipurpose sensor
1 Ecolink motion sensor
2 Ecolink door sensor

I have set up all rooms in the house with the “Smart Lighting” SmartApp to turn ON light when the motion sensor is triggered and if certain amount of time (varies by room type) has passed with no motion detected, then lights will turn OFF. Also, I’ve made sure all devices are using LOCAL PROCESSING to eliminate any potential internet issues.

What seems like a really simple concept and should work flawlessly ended up being pretty unreliable in reality.

The types of failures are:

  1. Person enter room, sees motion sensor light blink, but light does NOT turn ON. This is not even lag, it just straight up wont turn ON. I would have to leave the room to let it pass the motion sensor timeout period then re enter the room again for it to trigger the lighting automation.

  2. Person leaves room, time has passed the predetermined time on “Smart Light” SmartAPP and light still stays ON. Similar to 1), I would have to enter room again to re-trigger the motion sensor (i see it blink) and leave room again, THEN it would turn off the light at the predetermined time.

I would say that the smart lighting automation by motion sensors works about 75~85% of the time. This is simply too unreliable for practical use, family members at home are too annoyed to rely on it and ended up going back to switching ON/OFF manually. I’ve spent thousands of dollars on smart devices and professional installations and rewiring, and so far i’ve been pretty disappointed with this entire “smart home” concept. I’m keeping my hopes up tho and I’m wondering if anyone has run into similar issues and was able to fully resolve it. Any help would be greatly appreciated.

List of potential issues that I have thought about:

Z-Wave MESH - I have ruled this out as a potential issue because I have GE switches in every single room in my house and the locations of the switches are very evenly sprinkled across my entire house (also its not a big house by any means). Another reason why I’m confident its not the mesh is because so far I’ve been able to achieve 100% reliability when I switch lights ON/OFF if i use the SmartThings App. If the mesh was weak any where I would have noticed failures thru the app by now.

Z-Wave Interference: This is not possible, I’ve in a country where the 908MHz spectrum is not used at all, therefore there is no way any of my neighbor’s z-wave is interfering with mine (z-wave devices not sold here!). Also as I’ve stated previously turning lights ON/OFF thru SmartThings App as been 100% reliable so far, so i doubt there is any interference with the 908MHz spectrum. I’ve also consulted local authorities regarding my use, they basically verified the spectrum is not currently used for anything and told me they have no issues with it but if it ever becomes a problem they will ask me to take it down (which I have agreed to).

Faulty Motion Sensor - This I’m not so sure about but I think its highly unlikely since it has happened to almost every room in my house. Its not just one specific room or specific motion sensor that it has happened to.

Hub - This is the one I’m wondering. So far I’ve verified that all my devices are running locally so i guess I’ve eliminated the possibility of internet issues. So could it be a problem with the V3 Hub’s hardware being too weak/unreliable? Are the specs of the device built to be solid for home automation? Honestly, I also doubt this is the issue here, because you would have thought by the third iteration of the HUB they would have hashed out all the inadequacies of the system.

Any suggestions are greatly appreciated!

Have you ran a zwave repair to make sure that your battery operated devices can get reliably back to the hub? I understand your mains powered switched are turning the lights on/off but if your battery operated sensors can’t get back reliably…

What do your logs show? Are the motion sensors showing as active when the lights aren’t turning on? Are you seeing an on command sent to the lights but they aren’t turning on? I always start with the logs to see what is happening and then try and work from there.

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While your zwave sounds solid, your zigbee May be lacking.
These devices are not zwave and if they are too far away from your hub, they my work intermittently. Also wifi may cause interference with zigbee devices as well…depending on setup.

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The first thing I would look at is the placement of the motion sensors. All of the sensors that you describe are PIR (passive infrared) and all detect in the same way: by a very small change in heat moving across the lens. Consequently if you have placed the sensors the way you would place a camera, so that a person entering the area is walking straight on towards the sensor, that is actually the least likely to detect the person in a timely fashion.

See the community FAQ for more discussion of placement and other tips to get better speed and reliability from your motion sensors:

FAQ: Where to locate motion sensor for fastest response?

I don’t see any Zigbee repeaters in your setup such as plugs…You need to have a strong Zigbee mesh just like your Z-Wave mesh. Only need a few to achieve.

Also, placement of the motions are important.

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Yes I’ve ran multiple z-wave repairs and the results are the same. However I’ve never thought of checking the log. I will do that the next time it happens again, maybe I’ll get a better idea of what’s going on. Thanks for the tip!

The Zigbee sensors are actually in the same room as the hub itself in fact it’s like less than 10feet away and in clear line of sight. Also Out of all the sensors I’ve only had the Zigbee sensor fail once.

Yes I’ve tried placing in spots where the sensors get a good cross section motion. In fact it was one of the first thing I did to try resolve this.

From everyone’s response so far, it seems that all of you have managed to get motion sensors to work 100% reliably?

I guess that’s a little comforting to know that at least the possibility of a reliable system is there. Must be something else thats messing up the network, I just have to figure it out.

Are your devices running in the cloud or local?

Getting things running local by using the standard DTHs may help.

Nothing runs 100% reliably on any platform, and SmartThings itself adds another layer of unreliability, but certainly I have mine operating reliably enough that it’s a surprise when it fails, which is good enough for most residential applications. :sunglasses:

So it can certainly be done to that level, but it can require some trial and error, working one motion sensor at a time, to achieve it.

It also depends on just how smart you need it to be. Hands down my most reliable motion activated lighting is a non networked $20 switch from Lutron in the laundryroom. It doesn’t connect to anything else and it doesn’t have a lot of options, but it hasn’t failed in two years, someone walks into that area, the overhead light turns on, and it turns itself off after a set period of inactivity. Simple and as close to 100% reliable as I’ve seen. :wink: lutron advertises these as being “three times more reliable than the competition.” Not sure about that, but if all you want is a simple motion sensor switch, it’s great. We have another one in the closet with the water heater. No voice control, no alternate schedules for different times of day, but for areas where all you need is hands free motion activated lights it’s a good solution.


In other areas we use other, smarter, networked options, several different brands. All are acceptable, although some are slower than others. But it did take some tinkering with each to get it right.

All my devices are local

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Do yourself a HUGE favor and order the below plugs. They are freaking great and will fix your Zigbee mesh issue.

Do NOT use the Z-Wave repeater ability. These are new but in bulk. Spread them out over the house. They also monitor power usage!

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