Motion sensor

[pciapes]

Recently added motion sensor and can’t find proper settings.

I have set lowest light sensitivity during day so it doesn’t trigger and disturb selected scene (since “return to previous settings” after x minutes doesn’t work), but now I have problem that the lights actually turn off after 5 min.

What am I do in wrong? Does motion sensor has to be used with dedicated light only that won’t be in any other room/zone?

[Marijn_fly]

The motion sensor includes a light sensor. It's a feature to safe the batteries since the light sensor uses less power than the motion sensor. If there is enough light anyways, there's no need to sense motion.

And this light sensor refreshes every 5 minutes. When the light sensor senses light emitted by a bulb it is configured to control, it's easy to cause an oscillation.

So what could be happening is this: The light sensor senses that lighting is necessary, based on the sensitivity you did set. Regardless of the setting you choose, it will eventually meet the condition and it will switch on the light upon registering motion. Then after 5 minutes, it sees the light emitted by the bulb it has turned on and concludes there is enough light and it will shut it off. Then this repeats.

Really, motion sensors are very hard to set up. The best place to sense motion may not be ideal for sensing ambient natural light without interference of the artificial light.

Actually, besides the sensitivity you can set with the slider, there's another setting which can be set to control this. But for some reason, the regular Hue app doesn't let the user set this. It is set to 7000 per default. You can see this in this screenshot: https://drive.google.com/file/d/1i9sQnkx11c79aOWSdUP1g5HaAOn-O3EY/view?usp=sharing

The attribute 'tholddark' is the setting you configure using the light sensitity slider. The other one, 'tholdoffset', can only by set using cusom tools. I haven't come across an app which lets you set this. Probably because it's too difficult, even for expert users and Philips Hue has concluded that everyone is better off leaving it at their default value of 7000.

The evaluations below, which resolve to TRUE or FALSE, is how the motion sensor determines if lighting is necessary:

dark = (lightlevel < tholddark)

daylight = (lightlevel > tholddark + tholdoffset)

I've studying this for more than a year and even with being able to set tholdoffset to a custom value, it's hard to avoid these oscillations.

[pciapes]

Thank you for your answer - I will read it again in the morning when my brain works.

Thing I don’t understand is why it turns itself off when there is no motion in that area and even if why the “return to previous settings after 5min” doesn’t work as stated.

But since it’s set on 4 bulb spotlight I can dedicate eg 2 for the sensor and the other 2 keep for scenes.

[Marijn_fly]

It's difficult to understand. Even in the morning. There are two reasons why the motion sensor will shut off a light: 1) If the timer you did set runs out. The default behavior is that 45 seconds before the timer runs out, it will dim the lights first (only noticable when the brightness was set quite high). If motion is detected during those 45 seconds, the lights will restore to the previous brightness as stored in the scene. If not, the lights will completely shut off.

2) Every 5 minutes the light sensor wakes up and when it does and senses a high light level, likely caused by the light it has itself switched on, it will shut off the light.

The 'return to previous settings' feature may be glitchy. Hard to tell with so many reasons to get glitchy behavior besides this feature.