Motion detection power switch with timer

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sudo

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#318929 5-Mar-2025 21:47

Anyone know of any residential power switch sensors, that have flexible programming capability.

As well as timed powering on a light and exhaust fan when entering a bathroom, also have the ability to override, by pressing a button sequence, to stay on or switch off.

MadEngineer

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#3350600 6-Mar-2025 08:31

Yeah the term you’re looking for is occupancy sensor. Very common devices, used especially in bathrooms and even offices.

You're not on Atlantis anymore, Duncan Idaho.

richms

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#3350727 6-Mar-2025 15:33

I had one on a hallway light before I got smart downlights and a zigbee sensor. It was a standard flush box sized thing with a sensor window and an off/auto/on toggle below the sensor hole. Under the cover was 2 screws for light level and time.

Richard rich.ms

sudo

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#3350771 6-Mar-2025 17:47

MadEngineer:

Yeah the term you’re looking for is occupancy sensor. Very common devices, used especially in bathrooms and even offices.

The ones I have seen are timer only ... no override etc.
For example if you are in the shower, it may turn the light off after 5 minutes of no motion sensor (had this happen to me in a office bathroom)

You know of any examples of devices?

richms

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#3350815 6-Mar-2025 23:54

The one I had was just some piece of crap made by one of the generic electrical brands about 20+ years ago. It ourlasted its usefulness when smart stuff came along but it was still working. I think it was a PDL thing but I am certain that all the brands have done the same thing.

Richard rich.ms

MadEngineer

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#3351576 8-Mar-2025 20:35

sudo:

MadEngineer:

Yeah the term you’re looking for is occupancy sensor. Very common devices, used especially in bathrooms and even offices.

The ones I have seen are timer only ... no override etc.
For example if you are in the shower, it may turn the light off after 5 minutes of no motion sensor (had this happen to me in a office bathroom)

You know of any examples of devices?

Get one that's microwave based. They too come with downfalls though as they don't care for walls and they can be triggered by water running through pipes, meaning you have to set and position them carefully.

Any sparky will know how to wire in an override

Example for a PIR model

Lots of ways to wire them. You could add a fan timer that's triggered only when the light comes on for example

What's the actual use case here and what do you want exactly to happen? Does the bathroom have natural lighting?

You're not on Atlantis anymore, Duncan Idaho.

sudo

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#3352848 11-Mar-2025 21:15

Yes it's got natural light. This is mainly so I can have a night light and auto-fan extractor turns on. But I am liekly to add plantation shutters, so if closed it will be dark.

My current thinking is its timed for 5 minutes, unless you press a button where it stays on.

I'd like it to be flexible, so I can change the behaviour.

I'm also thinking of a separate circuit with the night lights running on the sensor. This was if you want the main lights on, you can switch them on manually. Not sure about the extractor, as I don't necessarily want the main lights at 3am when I want to go for a quick pee.