Question regarding three Smartthings Hub v3

For a specific reason, I want to use three hubs. My question is that is it possible to control devices from all three different hubs? For example, if a motion sensor from hub #1 is activated, then turn on/off a device from hub #2.

Is there any difficulty that I should know?

yes, its possible if they are setup in the same location.

But three hubs in the same location although technically doable isnt a supported configuration it really should only happen when transitioning between hubs.

Why three hubs?

Fair enough. I have a specific reason to use two and I use them on the same location without issue.

You will be able to find a support article suggesting that multiple hubs on the same location are not supported. Equally you will be able to find one that simply puts it as ‘It is not recommended to add a SmartThings Hub to a location with an existing Hub.’ The latter better reflects reality as clearly both the current and legacy platforms don’t bat an eyelid when multiple hubs are encountered on the same location, and even ST Support will happily address issues with more than one hub.

I doubt you will find any ST staff encouraging you to do it, but neither will you encounter anything much more than ‘your mileage may vary’.

I think if you try hard enough you might find something that doesn’t support multiple hubs. The only issue I am aware of is that if you use a hubAction in a legacy SmartApp to make an http request on the local network there is no way of specifying which hub to use and no default, the end result being requests made from each hub (itself not necessarily a problem).

It will be interesting to see if the guidance changes once the legacy platform is phased out.

3 Likes

It’s all about the weak signal issue.

My situation is:

  • I set up a hub at the center of lever #1.
  • There are three Aeotec Multiple Sensor 6 nearby, about 2 to 7 meters.
  • Zooz ZEN16 at the garage (the same lever, not like the basement), the distance from one of above Aeotec multiple sensors about 4 meters, separated by a brick wall. The distance from Zooz ZEN16 to the hub is about 8-9 meters, separated by a brick wall.

Issue:

  • The signal too weak, the Zooz ZEN16 always in offline mode. I couldn’t turn on or off the relays.

Someone may recommend me to use Range Extender. However, I don’t know whether it’s efficient. The point is all my Aeotec Multiple Sensor 6 are set up as ‘powered’ mode, which means it always acts as a repeater.

My aeotecs in powered mode do not reliably act as repeaters. If youre relying on those as your repeaters, youre likely going to have issues. This is likely due to ths fact that these devices are USUALlY battery powered and a lot of their functions seem to default that way.

I would not use a ‘range extender’ either. Instead just use pocket outlets or smart switches. They’re generally the most reliable repeaters and if you need a repeater just slend the money on a device that does something you need. I can’t recommend any specific device though unless we know your geography. Location matters…

I worked IT operations and support for 20 years. What I learned ovef that time… Developers suck at testing any scenario that isnt default and just because something ‘can’ wotk does not mean that it should be done. I would build out a proper mesh here in your situation with repeaters OTHER than the Aeotec sensors. Reason is from what you described, if you have multiple hubs you still will have a poor mesh. (read: signal issues) whereas if you fix the underlying issue with repeaters you wont need multiple hubs.

With all the changes going on in the system right now, if ST says its not supported believe them. Because that basically means it may work today but ST didn’t intend for it to work so it may stop tomorrow without warning and they’ll just say ‘told you so’ if you try to open an issue on the matter.

1 Like

So which solution I should use? Range Extender?

No. Pocket outlets. Wall switches, but again i cant recommend specifics unless we know shat country you’re in. Device selection and availability varies greatly by location.

2 Likes

I would check out the new Zooz 700 series switches they just released yesterday. They repeat and 700 series has a longer range than previous generations. They are less than $30 too.

2 Likes

Extra hubs won’t do anymore to help the weak signal issue than just adding additional repeating devices, either Z wave plus or Z wave plus V2 (the new 700 series). As both @nathancu and @Automated_House suggested, just a regular plug-in pocket socket is usually the easiest, but zwave light switches and zwave lightbulbs are also good repeaters. You just have to strengthen the mesh that you have.

See post 11 in the following thread, then go up to the top and read the whole thing and it should help clear up the confusion about repeaters.

This link goes directly to post 11. The topic title is a clickable link.

As far as single purpose repeater devices, those were needed back in zwave generation three and four, but by Generation five (which uses the marketing name “Z wave plus“), pretty much every device transmits at maximum allowed signal strength anyway, so you get more value out of a dual purpose device like a pocketsocket or light switch. :sunglasses:

I personally like this one from the smartest house Zooz brand. The price is good, you get 2 independently controllable sockets plus a dumb USB charger slot. And it’s a very good Z wave repeater.

https://www.thesmartesthouse.com/collections/smart-switches-and-plugs/products/zooz-z-wave-plus-s2-double-plug-zen25-with-usb-port

Whatever devices you add, remember to do a zwave repair after you have added it or the old devices won’t use the new repeaters for a while. And don’t expect to see much improvement until the next day, it takes a while for the new route changes to propagate through the network.

BTW, You may already know this, but it’s likely that it’s the brick walls which are killing your signal. It’s hard to get signal through those. I’ve known people who had to bounce signal from a second-floor window down to a garage window in order to get it inside the room. And even the wooden garage is are almost always a problem because they tend to have a lot of big metal objects, a lot of cement, even pipes. You just have to do some trial and error to get a good route. Zwave light bulbs can sometimes be useful in situations like these. :thinking:

1 Like