We’re looking after a hamster for a week. Not wanting it’s infernal scratching keeping us awake, I want it downstairs, but we’re alarmed to the nines with PIR sensors and the like.

Will it trigger them?

I doubt it. Our cat doesn’t set ours of

Hedgehogs can trigger security lights. They are bigger than a your hamster but smaller than robbo’s cat to state the obvious.

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Maybe teach it to attack burglars and then switch the alarm off?

Just lay a tea towel over the cage overnight. PIR will not see heat/movement.

Surely you don’t need to set the alarm while you’re protected by a hamster.

Just lay a tea towel over the cage overnight. PIR will not see heat/movement.

And this  is why the police have never been able to catch  the notorious Nativity Play Burglar

Ours didn’t.  He’s gone now to hammy heaven….☹️

Bloody spiders occasionally set my garage PIR off by walking across it!

I get spiders setting my garage one off too. Updated to a smart camera which is much better but still gets fooled. As for the op, can’t see it being an issue if you put the cage in the right place.

PIRs detect movement across the beam most effectively. Put the cage directly below the sensor and you should minimise the amount of beam to move through, if it covers that area at all

Some PIRs have a pet setting where you open the enclosure and move the innards so that it can’t “see” low height movement

It’s not worth taking chances. Immobilise the hamster overnight either using a powerful tranquilliser or by feeding it malt whisky. Don’t attempt to restrain it physically, hamsters have Houdini-like qualities and will assuredly escape and attempt to wreak a terrible revenge on you.

Right then, I covered the cage with an MBUK and a towel.

The PIR didn’t go off.

The bloody hamster ate the MBUK and the towel.

My rats don’t set mine off, it might be a different story if they are loose around the house but just generally hanging out in the cage they don’t.

Oh and you will probably find a hole in that tea towel later, they love to turn fabrics into bedding material.

Bloody spiders occasionally set my garage PIR off by walking across it!

The hamster is in a cage so it will be unable to reach the PIR.