- You can add a total of 231 zwave devices to any certified Z wave controller, that’s part of the standard. So that includes a SmartThings Hub. As to whether you would see slowing above 125 to 150 devices, that depends on a lot of different things including the local architecture. So it’s just hard to answer.
That said, smartthings is a multiprotocol platform and you can also have zigbee devices, Some specific LAN devices including a Logitech Harmony home and a Phillips hue bridge, some cloud to cloud devices, etc. So there are members of the community who have 300 or more total devices, but they aren’t all zwave.
@johnconstantelo has one of the larger installations and may be able to say more about his experiences.
- with regard to wiring a smart switch so that it is no longer connected to the load, that’s very doable, but it does depend on the specific model and I’m not familiar with the wiring for that particular Leviton switch.
More commonly in the community people will buy one of the auxiliary switches that has its own Z wave radio, such as the Linear/go control WT00Z, which is designed not to control a load and use that. So you press on the switch, it communicates to the hub, and then the hub does whatever you have set it up to do through your automation rules. Which could indeed be controlling lights on other circuits or changing the mode or running a routine or whatever.
And as long as it is not wired to the load you can certainly have pressing the top do one thing and pressing the bottom do something else.
https://www.amazon.com/dp/B00EAY3K5Y
There are also several dozen other devices you might consider, some of which are battery operated. The remotec 90 is particularly popular because it has eight separate buttons, each of which supports tap, double tap, and long hold, giving you 24 total functions. And it can be labeled, which is nice for visitors. All for the cost of about $45.
See the following FAQ for discussion of a number of other possibilities as well. You might see something there you like. Some of these are wall mount, some of these are tabletop, some are battery operated, and some are mains powered, so read the descriptions carefully.
- Finally, as to the Leviton zone controller (that’s what the “Z” in the model number stands for) versus the Leviton scene controller (“S”)
The VRCS4 can be made to work quite well with smartthings. The VRCZ4, however, is an older device which relies on zwave command sets which just don’t really work in a multiprotocol environment such as smartthings uses. It’s not impossible that someone got it set up so that pressing a button on the Z4 would cause a Z wave lamp in the same room to go on or off but smartthings wouldn’t know that you had done it (so the app would get out of sync), you couldn’t use it for devices on the other side of the house, you couldn’t use it for any other smartthings function. It’s just not a good match.
But the S4 can communicate its button pushes to The hub, which then opens up a whole different set of possibilities. So there are community members using that one.