Check wiring please

PIRs in parallel (ie L-L, N-N, A-A) Flood lamps in parallel (A-A, N-N)

and of course all earths connected.

The *only* thing that could go wrong is if the PIR switches don't like live turning up at A when that unit has not triggered - not a problem if they have relay outputs.

Perhaps someone with wider experience of PIRs could comment on that bit?

Thanks Tim, its the Lidl PIRs which I believe is the ones on the link below.

Can't comment on your proposals, but a good few years ago now I did something similar with 3-core and earth: a PIR+flood, another separate PIR, and two separate lights. If either of the PIR's were activated, everything came on. Can't recall the circuitry in detail, but I think it just involved running the 3+E between all the units, and connecting appropriately, with a mains input at some point of course.

Page 5 has the symbol for a relay - if we take that literally, it is definitely fine. My observation is most mains switching devices that do not handle dimming seem to use relays rather than semiconductor switching.

And even semi conductor switches may not mind receiving live on their switched output, but some might. Relays OTOH are findamentally fine with this.

I'd go for it.

But why not have the 10W flood on a light-sensitive sensor, so it stays on all night? It would be a very good deterrent and the leccy consumption is negligible.

Bill

Should be ok. I'm using one of those Lidl devices in a situation where I have an over-ride switch which feeds mains live to A when I want the lamp on without triggering the PIR. That works fine - so if mains is fed in via another PIR instead, that should work fine too. As others have said, the load switching is almost certainly done by a relay so you'll just have two relays in parallel feeding two lamps in parallel.

I could do but I prefer the surprise element created when the flood comes on. If its on all the time it allows them to suss the place and find any weak spot. Also (my opinion) others are more likely to notice a light come on than one thats on all the time. Just my personal view so not necessarily correct.

The helicopter follows the lights that come on to find the people to arrest.

You should suggest that to the police to help them save money. Why waste all that money equipping their helicopters with bright floodlights and thermal imagining equipment when all they need is £5 PIRs in back gardens:-)

So would I

The FLIRS have a limited field of view, seeing a stream of lights coming on makes it easier to find where to point the cameras. I don't need to suggest it they already know.

Yup, it looks like a version of:

You can soon tell if you rig up one and trigger it - it will click. The semiconductor switched ones are silent.

A FLIR is not much use on a helicopter ;-)

That depends on how you define forwards.