Dusk sensors.

[Clint Sharp]

I'm putting some lights outside and quite like the idea of a dusk sensor to automatically switch them on.

I've seen a dusk sensor that is 'timed' (Toolstation 65651) does this mean that once it detects a preset light level it stays on for a timed period regardless of light levels or would it switch off again if the light level rose above the 'dusk' level?

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[Tim..]

Why would light level rise again within 6 hours after dusk?! lol.

Tim.

[pete]

ans: passing vehicle with headlights on.

[Andy Burns]

No clouds in your neck of the woods?

[Alan]

In message , Tim.. wrote

Because a light connected to the sensor has turned on :~)

[Andrew Gabriel]

Almost certainly uses this IC:

or so years ago, there was quite a clever chip which did dusk to midnight (or any other predefined time). It worked by working out which part of the year it was in by measuring the dusk to dawn time so it could estimate the real time of dusk switching and then work out how long to stay on, so the light switched off at a fixed time. First night, it stayed on all night, but thereafter, it switched off at the predefined time, improving accuracy over 8 nights. There were a number of products available which clearly used this internally. Can't find any trace of it now.

[Andy Dingley]

I've got those. They're so far reliable and insensitive to street lamps or headlights. Just be a little careful about where you're pointing the sensor.

Vastly better than the previous "smart lightbulbs" anyway. They were useless.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember pete saying something like:

No. They have a passing headlight reluctance delay.

[Dave Starling]

It probably fell prey to market forces due to the additional cost compared to a cheap dusk to dawn sensor. If you want it to switch off at a set time, then run it off a 24hour time. Couldn't view the link to the pdf.

I agree with the point of the light bulbs with sensor built-in. They ar s**te

On a similar note to interesting products that are no longer manufactured; the Danfoss boiler energy manager is no longer in production. I don't know when it was first on the market - maybe early

80's. Does anyone know more about it?

Regards, Dave.

[Clint Sharp]

In message , Alan writes

Exactly. The area I want to light is shaded from street lighting and because our council has just upgraded the street lights to some very bright almost white ones I suspect the only place I could put the sensor is in the area that needs to be illuminated.

[Clint Sharp]

In message , Andrew Gabriel writes

Blimey, I wouldn't have thought there was enough variance over a week to do that with any sort of accuracy, especially if the weather changed over that week. I'd be interested to know who made that or at least the part number.

[geoff]

I have a box with about 50 of them in, if I haven't thrown it out

[ARWadsworth]

> 30 or so years ago, there was quite a clever chip which did dusk

Newlec do a Part Night Photocell. It turns off at midnight but does not seem to be adjustable. I also turns back on at 5.30am if it is still dark. It claims to take 3 days to calibrates itself. Part nos NL5606 and NL5607.

The customer never got back to me so I assme that it is reliably turning off at around midnight

Adam