On Wednesday, 24 April 2019 10:32:29 UTC+1, tim... wrote:
Hi,

My new abode is in a block of flats that has interior lighting provided by
(60) bulkhead lamps which are mostly on 24-7 (with some controlled by light
sensors so as only on when it is dark)

I have been tasked with looking to see if we can replace some of then with
ones which detect movement so that they can be off for the large parts of
the day when no-one needs them

It seems that the style of lamps that we have now is not currently available
and I suspect there will be resistance to having different style of lamp
along the corridor so it's replace all of them or none of them

Currently the bulls we use are 2 times 7W CFLs and the smallest LED
replacement that can be styled with "Integrated" movement sensor is 10W so
replacing those lamps which will need to remain on 24-7 is going to be
negative (after the cost of installation ahs been taken into account)

So the end result of changing all of the lamps has to result in a very
significant saving from the ones which are going to go on-off overnight, for
this to be worthwhile.

Adding external PIR sensors into the supply is going to be a mess
(especially as the corridor was only recently redecorated and there's no way
that redecorating afterwards can be justified) so is it possible to obtain
just the internal microwave sensors and have them installed inside the lamps
that we currently have - there is plenty of space for this.

Anybody have an experience of this.

Is the project worth it for the saving to be made?
You need to work this out before you start.
Sounds unlikely to me.
Just fit the smallest LEDs as CFLs fail.

If there are staircases involved, movement sensors may not react soon enough to stop accidents.
(Dependent on siting.)