SNZB-06P Sensitivity

I have installed, in my son’s room, a presence sensor SNZB-06P- During the day everything is fine, but when he sleeps his presence is not detected. The Sensor is less than three meters from the bed. The day is often sitting at a desk, less than a meter from the sensor. Here every absence/presence is well detected. At what distance does the Sensor detect? The sensor is with high sensitivity.

The radar’s maximum detection distance is approximately 4 meters (high setting).
Sensor range

Tell us what you would like to achieve on the night? What kind of action are you interested in?
For most microwave motion sensors I know of, presence detection is somewhat debatable. When you stop moving for a bit longer, the sensors do not detect presence. Small gestures are not detected.

The Sensor is used to turn off the heating in the room when my child is at university or away for other reasons. But in the morning, when he sleeps in his room, the Sensor should turn on the heating by detecting his presence, even if he is sleeping, heating the room in anticipation of waking up. The heating runs from 6:30 a.m. to 11:30 p.m.

The presence sensor detects a person (object) when it moves. “Presence” does not mean that it is somehow miraculously focused on a person. The microwave sensor does not distinguish between people and objects. When your son is asleep, he is unlikely to move in any significant way unless he is having nightmares. So, the sensor is not detecting any change.
I understand that the plan is for the sensor to detect presence and trigger the heating, yes? You created a scene for this, right? Describe how this scene is built or post a screenshot.

The Radiator is set to 29°C but another scene turns it off above 22.5°C


I have the same problems in our living room. After a few mins of inactivity, the sensor cant see you anymore, and is set to “no presence”. And that’s from 2-3m away, directly in front of the sensor. Basically, the sensor doesn’t work. It’s a shame as it would be great if it did.

Give me some time to analyse your settings. At first glance, the scene is not going to work according to your expectations.
Perhaps someone else will have constructive comments?

It’s about price. Their sensor is cheap and doesn’t detect tiny motions.
Even if you semi-DIY it you still end up paying more than the cost of their item.
See here:

That sensor is $45 and you still need to buy something to connect it to your wifi, but it does say it detect breathing and heart rate.
I suspect you could get away with something cheaper but the duvet is going to suppress movements. Also if you’re connecting it via an iHost or NS Panel Pro you could set a trigger up so it only had to go detect every 30 minutes or so. Suspect the same is true in the cloud somehow. Maybe in the free version of IFTTT?

You can add a door sensor to determine when someone enters or leaves the room, or an additional snzb-03p sensor at the door to detect entry and exit.

The brutal truth about cheap sensors and products based on them is that they either detect poorly or are too sensitive.

A very good video some time ago @csongor.varga had where he showed the actual operation of the sensors and based on it you can clearly see the limitations of the product…

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OP wants to have a double trigger? It is possible to do this, but whether both will be present at the same time, which, as I understand it, is a problem with the scope of the sensor’s operation in the current situation.

In general, the OP’s concept of heating only when a person is in the room is quite specific… It’s a bit like shooting a mosquito with a cannon.
Simply turning on the heating for a period of time would probably be enough, and if there is a need not to heat when we know that no one is there, it could be done manually, but after all, it has to be automatic. :slight_smile:

Maybe putting the sesor in a different place or adding another one on the ceiling would help. Provided that the 06P will actually be able to detect a motionless person, which from the video above does not seem to be so certain. In addition, it must provide this information regularly for the trigger to be present.

Cameras with object/motion tracking and human detection are much better suited for such tasks than radar or PIR sensors.

I solved. First of all I must explain that my heating is shared and is on from 6:00 to 9:00 and from 2:30 pm to 10:30 pm.

My son still sleeps at home, except in exceptional cases. So in the morning the heating must always be on to prepare the room for his awakening.
So in the first time slot it doesn't matter if his presence isn't detected while he sleeps. In the second time band, the switching on of the heating is secondary to the detection of his presence, but it is a time band with activities capable of being detected well by Sensor (studying, working on the PC, playing on the PC).

So if he has not returned from university or other trips, the heating won’t turn on. If he is back in, the heating will turn on.

If someone enters his room for a short time, the presence of a person will be detected and the heating will turn on, but only for a very short time, because at the next check (and it is possible to program the time interval between the two checks) the absence of a presence will cause the heating to turn off.
This way I can save on heating for all the hours of the day when it is not needed.

If you know how accurate microwave sensors are, it is almost ridiculous not to utilise this technology better in SNZB-06P. Advanced features offer only 2 options - detection duration and sensitivity (low/med/high). It is advertised as a human presence sensor. But it seems to be extremely underutilized. It is certainly not capable of noticing your breathing. In overall, it is not much better than Sonoff’s PIR sensors. As usual, the devil is in the software. Hopefully, future updates will make the SNZB-06P a mature product. Like NSPanel (not Pro), this device has potential. Let’s hope it is not wasted.

I’m not necessarily talking about breathing, the 06P uses quite a low frequency and I don’t expect much from it.
The problem here is the overall software and the way in which old and new signal readings are processed.

The idea would be to build an image of space in a similar way to lidar or many other radar systems.
06P does not need to detect anything new to determine presence, it just needs to remember the state before and after the movement to determine the “presence” variable. And this does not require extraordinary accuracy.

My own tests show that the SNZB-06P simply does not work. You can be sitting 1.5m away from the sensor, and the sensor will register no presence after a few minutes, so it’s pretty useless.

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I suppose that you can overcome this issue just excluding the heating control by the presence sensor in the time slot of your interest and start the heating just by timer in that time slot

I agree on your description, but the misunderstanding that people aspect a miracle is consequence of the commercial description of the sensor, that state: Presence detection Based on 5.8GHz microwave radar, it detects movement or stationary person.
Description should state that stationary person means a person having micro movements

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Indeed! :grin: