"Limiter" for outside lights

[Peter B]

I've got a number of outside lights round the back and side of the house that run off a photocell and burn away through the night, lighting up half the county for nobody's benefit (other than e-on).

I'm trying to work out how I can make this better by either;

a) putting "a thing" in series with the photocell that only allows the lights to run for say 3 hours after dusk

b) putting "a thing" in series with the photocell to achieve a) but that switches over to a PIR sensor once the initial 3 hours (or however long I set) has passed

Suggestions appreciated as to what the "thing" might be and where it could be purchased (for less than the cost of the power consumed by said lights).

[Tabby]

If you want the lights on for 3 hrs then to switch to PIR, just put a PIR and timeswitch in parallel.

NT

[Andy Wade]

A series time-switch contact[*] would be a cheap & effective solution giving illumination from dusk 'til a fixed off time (and a from fixed on time 'til dawn on dark mornings if desired).

That just needs a PIR on same circuit feeding the lights directly, passing the photo/time switch.

[*] If your photocell needs a permanent mains feed (i.e. it requires a neutral connection) then you'll need a time-switch with a floating ('volt-free') contact after the photocell. Feed the time-switch 'motor' directly from the supply.

[ARWadsworth]

You have a number of options.

is a photocell that switches off at midnight and back on at 5.30am. You would then need to wire a PIR or manual switch in parallel with the photocell if you wanted to over-ride the off period. You have not said what the power of your outside lights are so I do not know if they are costing more than a new photocell.

I recently added outside lights to my brothers garage. These are operated by a normal dusk till dawn sensor but the output of the sensor passes through the switched terminals of a second hand CH programmer that I had. The programmer turns off the lights at 6pm everynight but allows him to over-ride if he is working late. It also switches the lights back on at

7.30am (if it is dark) for when he arrives at work. The added bonus is that the lights do not come on a the weekend. You can use any "volts free switching" timer as long at can cope with the power of the lights.

The trouble with just having the lights stay on for 3 hours after sunset is that in the winter the lights will go out at 8pm and in the summer they will go out at midnight .

[Andy Dingley]

These photocell controllers

a delay option. Dusk to dusk+2 or to dusk +4 is switchable.

[Scott M]

Rationalise what they are.

Some lights should be on switches - say on the back door to garage run - so you put them on and off as needed. No nuisance PIR trips at night; no stumbling out in the dark waving hands around to get them to come on.

Lights at the front/driveway on PIRs that'll be triggered by actual activity crossing the perimiter.

I've never understood the dusk-to-dawn thing for house lighting.

[Nightjar]

You can buy light controllers that start at dusk and run for a switchable number of hours.

run the photocell output through the contacts of a timeswitch that is set to switch on well before dusk and off whenever you want. This would also allow you to switch the lights on at a preset time in the morning, if it was still dark.

Colin Bignell

[Mike Barnes]

Peter B :

Are you sure you want a fixed number of hours rather than a fixed 'off' time?

As to what 'thing' you want, it would be helpful to know how the mains reaches the photocell and the lamps.

[ARWadsworth]

People use dusk till dawns because PIRs are usually s**te.

[Andrew Mawson]

e-on).

actual

I use dusk til dawn sensors and a timer in series, so they are not all on all night. In addition there are pirs at strategic points round the farm buildings & house. (20 pirs and 15 fixed lights at the last count!)

AWEM

[The Medway Handyman]

Exactly my view. In 25 years I've gone through about a dozen of the useless objects. Changed over to dawn/dusk with low enegry lamps & not a single problem since.

I will not supply & fit PIR lights. If the client buys one I will fit it - that way I don't have to sod about with warranty.

[ARWadsworth]

I'll fit the standalone PIRs. However the £6.99 B&Q 500W Halogen floodlights with a built in PIR are a no go unless the customer wants to forget the warranty.

[Scott M]

Actually, I agree. The bloody things often go short-sighted. Never quite worked out why (cleaned out the innards, etc) unless the sensor has a limited life.

But I favour them (or switches) over dawn-to-dusk! :-)

[John Rumm]

Standalone PIRs seem much better IME.

[Martin Pentreath]

I have three dusk-til-dawn lights at the back of the house for security. I live in inner London in an area of high crime. The back of the house is quite easy to get to and would be very dark without the lights. It's overlooked by a block of flats. Guessing the psychology of burglars is always going to be hit-and-miss, but I guess they would rather not be trying to force doors and windows whilst illuminated and in full view of lots of other windows. Even if the PIR things work it seems to be very easy to me to hop into the garden, trigger them, and then wait patiently for them to go off before doing anything dodgy. (In fact just moving very slowly seems to fool PIR sensors). My three lights burn a total of 21w between them, which I regard as pretty much negligible anyway.

PS In many years I have never had contents insurance (which is another story altogether), but I think the savings from this justify a few pence a month on dusk-til-dawn lighting!

[Scott M]

Forgot that in my other posts. Yes, the stand-alone ones I've never had problems with. The inbuilt ones (actually inbuilt rather than hanging below a floodlight) don't last 5 minutes.

[Andrew Mawson]

hanging

The ones hanging below can cause problems as well. I've had two now fill up with rainwater and go into permanently on mode. In fairness they are on an exposed gable end of a barn that gets all the weather. I silicone seal the glands on ones I put in now but even that's not infalable.

AWEM

[ARWadsworth]

It depends where the PIR aims. There are thousands of people attatching PIRs to the front of the house hoping to light the path up when a visitor walks down the path. Of course the PIR then picks up passing cars and for some reason (the reason is because they are cheap to buy) the owner usually has

500W of halogen lighting aiming halfway across the street. 20W of low energy lighting on a dusk till dawn (or a dusk till midnight) light will often suffice.

[John]

I've tried a couple of PIR lamps wired with another supply in parallel with the sensor. Both PIR semsors failed as soon as they were switched on. Do these things object to reverse voltage?

John

[ARWadsworth]

They should not fail like that. Wiring two or more PIRs in parallel should be fine.