Occupancy sensor / PIR

[^woody^]

I'm after an internal occupancy sensor/PIR, but not one that just turns on and off, rather one that dims for a while before turning off.

I don't know the name for this feature, and the ones I've looked at so far don't say if they do this or not.

So is this standard for all internal PIRs, or should I be looking for a certain type or name. Any recommendations for a ceiling surface mount type?

 

[jj4091]

http://www.mr-resistor.co.uk/item.aspx?i=7219

 

[ban-all-sheds]

That goes to dim instead of off, not dim and then off.

Requires lights with 1-10V dimming control - very unlikely in a domestic setting.

 

[JohnW2]

That goes to dim instead of off, not dim and then off.

Is "IP00" really credible? Would that not mean that one can touch live parts without any impediment?

Kind Regards, John

 

[Doggit]

That goes to dim instead of off, not dim and then off.

The time lag before switching off can also be adjusted. Please see technical tab for more information.

Is "IP00" really credible? Would that not mean that one can touch live parts without any impediment

Technically yes, but as its designed to fitted in plasterboard, they may be assuming that either it won't be touched, or that it'll have a fire cap covering it.

 

[JohnW2]

Please see technical tab for more information.

Talking of which, their 'Technical' section seems to think that a basin creates a bathroom zone.

Kind Regards, John

 

[ban-all-sheds]

The time lag before switching off can also be adjusted. Please see technical tab for more information..

I did - I think that means the time it remains on, after the last detection of movement, before it goes to the dim setting.

 

[JohnW2]

I did - I think that means the time it remains on, after the last detection of movement, before it goes to the dim setting.

I thought that, too - but it is all a bit unclear/ambiguous.

I think it has to be that way since the only alternative I can think of is that it goes to the dim setting immediately it ceases to detect movement, and then stays in the dim mode for the set time - but I rather doubt that many people would want that functionality.

Kind Regards, John

 

[flameport]

That type of sensor does not dim after a while - the dimming function is used all the time.

When movement is detected, the lights will be turned on but dimmed to provide whatever lux level has been set - therefore if it is bright daylight the lights may not turn on at all, or will be at a very low level; on cloudy days the lights will be higher, and at night near or at full power.
If the daylight changes with the lights on due to clouds or whatever, the dimming level will be adjusted automatically.

The lights are turned off once no movement is detected, there is an adjustable delay between no movement and switching off.

 

[JohnW2]

That type of sensor does not dim after a while - the dimming function is used all the time.

Thanks. That makes sense and, having read it a few more times, I can see that the description can be read as saying that. However, I would say that it is very poorly written, witness the several different interpretations which people here seem to have made.

Given that, it clearly does not satisfy the OP's requirement - are you aware of anything which does ?? As I understand it, he wants a 'slow/soft' (gradually & progressively dimmed) 'off' after the time delay following cessation of movement (without any 'lux control' whilst movement was being detected, or for delay period thereafter). I would think that would be fairly easy for someone to engineer - if it were an integrated sensor/LED light, in the crudest form, just a very large capacitor across the DC feed to the LEDs would probably do it.

Kind Regards, John

 

[^woody^]

To clarify, the sensor will be for the garage/workshop light.

I thought that if a normal PIR was used, if I was standing still, then the PIR would not detect any movement across zones and so turn the light straight off. So I thought about something like we have in the office where if no one moves (which is quite often, LOL) then the lights dim first, so you are not plunged in to darkenss, then you and shuffle a bit to bring the lights back on full.

So that's the requirement really, if there are other ways to acheive it.

 

[ban-all-sheds]

I can think of another way.

An on/off switch controlling the lights, mounted in a convenient and easy to access location on a wall.

 

[JohnW2]

I thought that if a normal PIR was used, if I was standing still, then the PIR would not detect any movement across zones and so turn the light straight off. So I thought about something like we have in the office where if no one moves (which is quite often, LOL) then the lights dim first, so you are not plunged in to darkenss, then you and shuffle a bit to bring the lights back on full.

Thanks for confirming. As you will realise from my previous post, that was my understanding of what you wanted.

I can't say I've seen any such animal but, if you have one in your office, they must exist (or have existed). As I said, it didn't ought to be that difficult to produce one.

What are readily available are 'hi-lo' PIR lights (and maybe standalone sensors). After the timed period with no movement, they switch into a much lower brightness mode - but that persists indefinitely, so you would have to eventually switch it off manually if you wanted no light at all.

A rather untidy workaround would be to have two PIRs and two lights, one having a longer time delay and a much dimmer light. At least both would then eventually go off in the absence of movement. It might be possible to have two PIRs and one light (fed via a dimmer), but that would require a bit of experimenting.

Kind Regards, John

 

[333rocky333]

The one in the link looks like a Danlers a better description here, though thats not want you want
http://www.danlers.co.uk/images/downloads/catalogue/PIRs with Daylight Linked Dimming.pdf

The sequence you want, is called step down illuminence, its often fitted to lights with dimmable ballasts and communicate with 1-10v, after a while they go to about 30% then later go to off.
Not sure you can get other versions


https://www.danlers.co.uk/pir-occupancy-switches-with-step-down-illuminance

Most stay at low level for safety rather than go off, we got ours from Morgan Hope Lighting that done the 3 stages including off but they were for 1-10v dimmable ballasts

You may find one here
https://www.mylights.co.uk/images/pdf/CP Catelogue.pdf

 

[ban-all-sheds]

Woody - have you got 1-10V dimmable lighting?