Can leaves set off security lights?

[d000hg]

We fitted a bunch of security lights as we're out in the woods, but it's backfired because they keep turning on which makes you more creeped out!!

I suspect we have a cat or fox doing the rounds but also, would leaves rustling in front of the sensor cause a false alarm or are they IR rather than motion sensing before I get the pruning shears out?

 

[Burnerman]

I suppose, as a long shot, any movement of anything would trigger some sort of temperature differential......I have the same issues. Its usually a cat or whatever but a flapping cover on my garden tractor has a similar effect so in winds I switch the lamps off.
A spider in the lens took longer to diagnose!
John

 

[bernardgreen]

Yes moving leaves can trigger a PIR

 

[stealthwolf]

I've had teatowels on the line trigger our PIR sensor. The teatowels were dry - the missus had forgotten to bring them in, so I ended up doing it.

 

[scbk]

Don't forget there's usually a dial to adjust the sensitivity on the PIR, and maybe try changing the angle it points at.

 

[d000hg]

But sensitivity also affects the light level, which we have about right.

I'll check for things in the way though.

 

[scbk]

The standard run of the mill PIR detectors have 3 dials - light (darkness), sensitivity, and time (how long it stays on for)

 

[d000hg]

I'll check that, thanks. I might've been thinking of the older one that definitely only had two.

 

[stealthwolf]

Ours is a "modern" one - only a year old and has two dials. One for daylight/night time cutoff, and one for duration. Sensor is adjusted by moving it up and down (or side to side).