Question about two ST motion sensors in the same room

Can I put two motion sensors in the same room? It is a room separated where one sensor would be mounted for each side. Can I have two separate motion sensors control the same ceiling lights using SmartApps for automation in the ST app?

I am running through SmartApps in the ST app and I can’t tell if it is a “AND” or “OR” type of situation when it comes to the motion sensors and turning off the lights.

If motion is not detected on one side will it shut off the lights?

You can choose “AND” or “OR” based on your needs. How the lights turn on/off really depends on 1) what you want the behavior to be; and 2) how you write your Routines.

Yes, you can use two sensors to control the same light.
If you are using the Smart Lighting application and choosing two sensors - the logic will be AND.
Using Routnes as in previous reply, is a way to go if you want to have either or ANY of the sensors (conditions) to turn on the light.
You would need to have a separate routine to turn off the light, but now if ALL of the sensors do not detect motion for X amount of time.

Ok, thank you guys. I will look into a routine. How is a routine different though from using Smart Lighting?

As mentioned above, when you select multiple motion sensors in a Smartlighting routine, the logic is AND which means both devices must detect motion. If you want to trigger on either of the motion sensors, you would have to have two routines. In a ST Routine, you can also have the logic be AND, however, you have the option of either devices detecting motion which is OR logic. Also, I know Routines run locally on your hub, but I believe Smartlighting is still running in the ST Cloud.

Unless you are trying to do something super complicated, I would try to stick with Routines as much as possible.

makes sense, thank you Bruce. I’ve got a newer version of the Phillips Hue motion sensor on order so I am looking forward to trying this. I didnt know routines ran locally either which is super cool, thanks for the heads up on that one.

According to the ST subreddit, the 2022 version of the Hue sensor works on ST without having to install a driver so we’ll see if that is true.

Just note, Routines run locally when they include just devices that use Edge drivers. Devices that are supported via a cloud->cloud integration don’t run locally.

Smart lighting runs locally if the devices involved are eligible. Each Smart lighting routine will get the house-with-checkmark icon of it is local.

This was also true of the Groovy-based Smart Lighting and was one of its advantages.

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