stairway photocell advice?

[shadyspark]

been given a job to fit photocells in a 3 storey luxury residential block, lights are on 2 circuits for top and and bottom levels. they are constantly on and only switched from the fuseboard and keyswitch controls mounted next to the db.

think 5 lights per level on the stairs, one of those a non maintained emergency.

4 lights in the detached landing per level

whats the best way to fit these photocells, many different ways into stairwell so i thought about fitting a photocell on every fitting.

no wiring light to light as pvc clipped with capping under palsterboard
or maybe could make some mess

any ideas or advice?

 

[electronicsuk]

What? Are you really talking about photocells or are you actually referring to PIRs? If you do mean photocells, then it would make sense to install one per level near the entrance with the least natural light.

There's no reason you can't install one per light, but it might look a bit naff if some come on before the others.

 

[shadyspark]

yeah bud meant pirs with photocells so they only work when dark, and yeah they will be energy saving lights that will naturally come on at different times.

would be at this for weeks trying to wire remote pirs, as its a finished stairwell. but i agree would be better

wouldnt it be a nightmare maintaining loads of PIr's?

and should i just urge them to convert lights to led?

 

[ELZ4742]

theres always the option of replacing the fittings with ones that have an in-built pir.

 

[Taylortwocities]

If you have multiple photocells, you will have to think carefully about where they are placed.

Lets say photocell 1 is in a relatively dark area. This light will come on first.

A neighbouring photocell (lets call it 2) may never operate as it will be affected by the light operated by photocell 1.

Multiple photocells will get even more confused. It is normal to have only one photocell, situated outside and away from other light sources (eg street lamps).

 

[flameport]

If they only want these lights on at night, forget the PIRs and photocells and fit a Sangamo solar timer at the DB.
If there are 2 circuits, a small contactor can be used to switch the second circuit.

 

[seasickstevie]

I've had flameport's suggested set up for some time, with a seasoned Sangamo.

Problem is when you sometimes get very dark afternoons or early mornings and they don't come on.

Then you can have a sunny evening, yet the lights are on unnecessarily.

I often find on dark winter afternoons, I have to go into the meter cupboard to override the Sangamo.

Think a strategically positioned PEC (or PECs - one for each circuit) is favourable.

Although the best idea is of course an occupancy sensor on every landing and hallway.

 

[OwainDIYer]

If it's a luxury building then residents may not appreciate the lights flicking on and off.

I have a PIR on the stair light outside my door, it sometimes needs arm-waving to come on, and is affected by whether other lights on the stair are on.

Sometimes having two photocells controllign one-third and two-thirds of the lights can be approrpriate; one-third of the lights come on when the ambient light is reduced eg cloudy days, the two-thirds comes on at dusk i.e. the photocells have different sensitivity settings.

In terms of costs of wiring and labour though, with energy efficient lighting using so little lecky it may not be expensive to leave the lights on. I have Coughtrie fittings which take CFLs (which are on offer at 10p each in Tesco - I have stocked up) and 9W per landing is ample.

It's not like the bad old days where current was 1/- a unit and the lights had to be on a timeswitch and if you came home after 10pm you were in the dark (lived in closes like that ...)