Issues with Sonoff SNZB-03 motion sensor

This happened with mine sonoff sensors, too. I stopped using them…

I use conbee2 stick with deconz.

Same problems here! They are absolutely unreliable. I have 5 sensors for 3 months now and the problems are the same as I read here. I am really thinking in selling them. Any suggestions for better motion sensors?

Sucks that I’ve already bought $90 worth of sensors, only to discover they are not far from being junk. Between the sends ‘occupancy:off’ despite continued motion in front of the sensor, to the false positives, I am severely disappointed in the company I’d always heard good things about.
These issues arent sporadic, they are widespread in any forum I read that has a topic about them.

I dont see any firmware update roadmap either, so I guess its safe to say these are a bust and everyone should avoid them like the plauge…

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Why call them junk… just base you automation on the OFF state instead of the ON state and they will work like a charm… I had an automation with these sensors that relied on the sensor refreshing the ON state every X amount of time (restart timer that would eventually turn of the light. This did not work according to plan due to these sensors not updating their state like we want them to. instead i now use the OFF state as trigger to restart my timers… works just as well…

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hi all,

I am new to this forum, but I am a linux and gadget nerd… I am still new to HA and still learning…
It seems everyone is complaining here, but how many of you have read
https://www.metageek.com/training/resources/zigbee-wifi-coexistence.html
and made a serious effort to ensure that your zigbee channels are set apart from the wifi traffic in your area.

G

Why call them junk?because they are junk!

And if all other ZigBee devices are working fine on our networks I would say that channel issues is not the problem here…

And how would it help to use off state ??
If the sensor is detecting motion even if there isn’t any?

Sorry for this little rant… but it’s very annoying when people who doesn’t read other posts before they start lecturing people about “why this”, and “why not do that instead”.

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If WiFi crosstalk was the issue, we wouldn’t be seeing regular patterned issues.

For me, stacking some paper in the battery compartment helped fixing the continuous alarms - now it’s functioning properly, nice continuous “clear” signals when there’s no movement, and no phantom movements either.

I’ve often wondered this when it comes to these threads about motion lighting.
I use person detection with some outside cameras to turn on outside lights.
I always restart my timers on the OFF state because I want the light to turn off X minutes after motion stops being detected. It doesn’t make logical sense to me to start the timer to turn off lights based on motion being ON.

Which also leads me to ask why the 60s cool-down time is such an issue? The only time I can see that coming into play is if you want to turn the light off within seconds of walking in the room. Is that the goal? For me, my wife would make me rip everything out if she happened to step out of the view of the motion sensor for 5s and the lights turned off on her.

Sort of unrelated to the SNZB-03’s but I ask in here because I’ve got a few of these sitting in my amazon cart right now. They’re as cheap as the Aqara sensors but I can get them in 2 days vs 2 months.

I have mine with conbee 2.
Doesnt work unfortunately.
It gives a constant state on. Once i change it to off (through the States Developer tool) it changes back to on after 60 seconds. Doesn’t respond to movement.
Don’t know what else to do.
Atm i removed it from the ZHA Integration until further info.

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I’d say the 60s isnt too much of an issue. I normally like to tie the light state to the sensor, so when the sensor is in state ON then the light will also be ON, and when the sensor returns to clear the light will turn off.
With this sensor, you cant really use it for presence. Once it detects motion its going to send that OFF signal in 60s no mater what is going on in front of it. Then on top of that, it wont even send another ON signal until its completely idle for another 60s. So if you leave and come back 30s after it turned OFF, it will not reactivate.
Pretty puzzling logic on behalf of Itead/Sonoff IMO.

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Lots of people have issues with these sensors btw: SONOFF SNZB-03 Strange Behavior · Issue #4874 · Koenkk/zigbee2mqtt (github.com)

I use zigbee2mqtt now, but I also had these when I had Deconz. Also acted strange there.

I used 8 of these sensors and some work fine while others have random issues. Like false triggers once a day, not triggering at all sometimes, or not sending the off-command after motion, leaving the lights on even when nobody is there. The 1 min cooldown wasn’t really an issue for me with my automations. But the other issues do break the whole point and reliability of home automation.

They’re nice if you have just started and don’t want to invest too much money yet or are still trying automations. But for homes where people live and you want stuff to ‘just work’ instead of having your lights turn off while still on the bathroom, these just aren’t worth the headache in my opinion.

I have solved all the issues with one simple solution. I purchased a Hue sensor. Yes they are expensive (€32-35 in stead of €9) but they work so so much better. I used 2 Sonoff sensors in each room, because I wanted to have a backup sensor since sometimes the sensors would’nt trigger on time or not at all. Now one Hue per room is enough. It’s extremely accurate, has great build quality and best of all: has a cooldown of 10 seconds that keeps extending if you keep moving. Also has a temp and lux sensor.

I just removed around 16-18 Aqara and Sonoff motion sensors and replaced them with 8 Hue motion sensors. After the first Hue I ordered 7 more the next day. Should have done this from the beginning. I use the motion sensors like 100 times a day, so cheaping out on these wasn’t smart in retrospect. Would have saved me a lot of headaches and even money with replacing faulty sensors and trying out different cheap brands (tried Konke, Blitzwolf, Sonoff, Aqara). I’m sure even Hue will get an occasion false trigger or glitch, it’s all wireless tech after all. But it works a lot more reliable and robust.

Btw: if you want the door sensor, do NOT get Sonoff. Opening has a one second delay before state change (closing is fine). Get Aqara instead, they work great :+1:t3:

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The Sonoff motion detector that was causing me the biggest headache is the one in the bathroom next to my office, so what I ended up doing is creating 2 separate automations based on time of day (it helps if you’re “regular” :grinning:). Motion detected between 9-10 turns the light on for 10 minutes, and motion detected outside of those hours keeps the light on for 2 minutes.

For higher traffic areas like stairs, I replaced the Sonoff with Hue Motion sensors, those babies reactivate within a second and definitely worth the price.

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Same thing here. The snzb-03 worked fine for a few weeks then started with the false positives. Now after having re-paired it a few times (to a conbee ii) it doesn’t register anything at all…lol

For those of us that are stuck with them, I hope a modification method is eventually released because they would be a huge waste

It’s interesting seeing other folks having similar problems.

I have four SNZB-03 sensors, all worked fine for many months, absolutely faultless & great value.
I use them with a Conbee II stick & ZHA.

Then they started sending continuous on/off signals very recently all day & night, often seconds apart and as others have witnessed, the batteries took a hit due to increased traffic. No surprise as zigbee is a protocol aimed at low levels of signalling with simple payloads of data.

I have a different suggestion I’d like to put forward as the possible cause. The SNZB-03 all worked fine until the recent drop in temperature where I live in the UK. I’m wondering if these sensors are not suited to low temps. The worst affected sensor is in my garage where temp are often close to 0.C. Even in the house when temps drop overnight below 15.C I’m seeing noise on the state history. Instead of seeing bands of green no motion, I’m getting solid brown state of continous switching from no motion (green) to motion (red).

When temps drop my devices seems to send spurious & frequent motion detection. The colder the greater the issues.

I brought them all to a warmer part of the house and the issues disappear until temp drop at night.

Would like to hear if this is the case for anyone else.

As a comparision I placed an ESP8266 with a PIR in the garage and I’ve seen no spurious motion signalling. Not a perfect comparison in fairness as PIR units may differ.

My plan is to move away from using these fair weather SNZB-03 sensors unless anyone has a fix.

Maybe it’s just me & the place is haunted! :laughing:

Hope this helps, let me know

Jaz

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@ jazlichy
In a parallel thread on the SNZB-03, I posted my experience with trying to operate a SNZB-03 outside in a Minnesota winter, where there are extended periods of outdoor temperatures below 32F (0C).
This week, overnight temperatures are dropping to -10F(-23C) and daytime highs are just getting into the single digits above 0F (-17C).

I tested the 2 Sonoff SNZB-03 units I have.
The first unit I tested started self-triggering when the outside temperature dropped below 26F (-3C).
The second unit worked until the outside temperature dropped below 10F (-12C).
When I brought them inside, they continued to malfunction until they warmed up.
I noticed that when they were malfunctioning, their battery voltage was way down to around 50%.
As they warmed up, I watched the battery Voltage recover. The units functioned normally once the battery Voltage had recovered to around 60%.

I didn’t grab screen shots of the SNZB-03 battery Voltage when this was going on, but I have captured the battery Voltage graphs of Sonoff SNZB-02 temperature sensors during our cold weather this past weekend. Note how the battery Voltage kept dropping and dropping as the temperature fell.
Temperature below 10F SNZB-02 Temperature vs Voltage SNZB-02
I replaced the battery before the SNZB-02 battery went dead and I lost the data from the sensor.
The same CR2450 coin batteries are in all these Sonoff sensors, and I believe we can expect the same behavior in cold temperatures.

I looked up the specs of the PIR sensor I believe is in the Sonoff units (3 pin, through-hole, metal can, PIR sensor with square window on top).
It’s operating specs list functionality down to -40C!
If true, the PIR sensor shouldn’t be the failure point.
https://www.murata.com/~/media/webrenewal/products/sensor/infrared/datasheet_pir.ashx?la=en

My conclusion is that the self-triggering is caused by sagging battery Voltage, due to cold, and the CC2530 Zigbee chip is probably rebooting over and over, transmitting the trigger signals over and over.

My proposed solution is to open up the unit and solder an external AA battery holder to the battery terminals.
2469 Keystone Electronics | Battery Products | DigiKey or
https://www.amazon.com/dp/B076C7S2VN
Two AA batteries (especially lithium AA batteries) should maintain a lot more reserve current when the temperatures drop below 26F (-3C), and thus the Voltage won’t drop to reboot levels, and it will continue operation in the cold. It will be ugly to have a battery holder hanging outside the unit, but I suspect this will solve the cold coin battery problem.

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can the HUE sensor trigger lights other than HUE?

If you use ZHA, deCONZ or zigbee2mqtt yes you can. You’ll need a Zigbee coordinator (USB for instance) that works with one of those add-ons. You can get rid of your Hue gateway and control different devices with different sensors (kinda the whole point of Home Assistant :wink: )

But this topic is about Sonoff SNZB-03 issues. If you want more info and see what the differences are between those three solutions, see -> deCONZ vs ZHA vs zigbee2mqtt - Configuration / Zigbee - Home Assistant Community (home-assistant.io)

right now all i have is a ZOOZ zwave stick. when you say Zigbee coordinator, you just mean a zigbee usb stick right? wonder if it’s worth it as in Canada that Nortek usb is $120 by itself.