Motion Detector

Projects General Guidance
1

Hi All,

I don't normally post these but gonna take a shot in the dark here, I'm looking for a motion detector that can be used with an arduino, Now I know most of you would slap me upside the head and say hey dummy go google it. I have, found numerous ones but not exactly the kind i'm looking for. I'm looking for an enclosed motion detector that is also adaptable for 5V logic.

1400×1400 80.6 KB

Something like this is what i'm going for. I do know that adafruit sells PIR motion sensors already capable but i'm going for something a bit cleaner. If anyone has any leads or brands that you KNOW would be worth trying, please do let me know.

Thanks,

  • M
2

Buy a cheap motion sensor that looks like your picture and use it. What the problem?

Paul

3

The one in the picture does seem like one you can use. I think the issue you are having is that you need an obvious way to interface 5V logic. Unfortunately, if you are not buying a hobby product, all you have are commercial ones.

My advice to you is to buy whatever motion detector that meets your specs. Luckily for you, pretty much all motion detectors have "dry" contacts, meaning, that nothing is connected to it and is really just a relay being switched on and off for you. For this contact, envision it being like the push button in this page

The rest of it now should be obvious. But come back if you need more guidance!

4

I think these all have a relay closure to signal an alarm
https://us.boschsecurity.com/en/products/intrusionalarmsystems/detectorsandaccessories/motionpir/motionpir_4897
You can cover a room, I think there is one that make like a floor to ceiling curtain, etc.

5

pretty much all motion detectors have "dry" contacts,

I have never seen the term dry contacts to refer to just a relay contact before someone used it this month on this forum. It is not a term that is used correctly in this context. Relay contacts can be either wet or dry and seeing how wet contacts are banned now in Europe due to a stupid EU law you can’t get them as readily as you could. A wet contact is one that has a very small amount of mercury on it to reduce the resistance and increase the contact area and were always sealed hermetic.

So a relay contact should not have dry attached to it as if it was a contact closure without any voltage on it.

6

Very interesting replies everyone! Like I said in my OP, this was more of a shot in the dark if anyone had any successful previous experience with a certain brand. I will do my best to find a cheap one and try it, and hopefully come back and post my results if I remember. (I'm terrible at that)

As always I appreciate everyone's input and thank you!

  • M
7

what's wrong with the simple Passive InfraRed sensor boards sold by adafruit and ebay and the like? The sensing parts all work the same and the PIR boards are already tapped to send a 5V output (ie: interface with an arduino)...

if you just want it to look pretty, build an enclosure for it.

8

Grumpy_Mike:
I have never seen the term dry contacts to refer to just a relay contact before someone used it this month on this forum. It is not a term that is used correctly in this context. Relay contacts can be either wet or dry and seeing how wet contacts are banned now in Europe due to a stupid EU law you can’t get them as readily as you could. A wet contact is one that has a very small amount of mercury on it to reduce the resistance and increase the contact area and were always sealed hermetic.

So a relay contact should not have dry attached to it as if it was a contact closure without any voltage on it.

Interesting! I never knew about the mercury contacts. I was referring to the indication that it is "volt-free", for lack of a better term.

9

As I said I have never come across the first meaning on that link in over 50 years of electronics, I am guessing it must be an American thing.