Z-wave virtual 3-way switch


#1

Hi there,

I am trying to determine if the smartthings environment is the right setup for me. I am planning on slowing rolling out a HA system. I have an ecobee and plan to get a smart sprinkler system for a new garden I am putting in, and so in general Smartthings seems to do what I want. However, I have an acute lighting project that my wife is requesting, and I need it to meet the following constraints. Insteon seems to do it fine, but I was hoping for a Smartthings solution as it seems to be a superior hub for all my other needs.

Here is my project:
-The sole kitchen light switch is in a hallway not near the door to the garage. My wife wants me to put in a 3-way switch (I can do the wiring, but it will be pain).
-Thus, I was hoping to do a virtual 3-way. Replace the existing kitchen switch with a z-wave and install a remote wall-mounted remote near the garage door. I don’t need dimming capacity.
-The system has to work if the wi-fi is acting up–ie if power is on but the router is on the fritz, it needs to work–thus I need direct Z-wave communication.
-I want the status of the z-wave switch to be synced with the smartthings hub for other uses down the road. The remote doesn’t need to be a device in smartthings, as long as the switch is any any change in status from the switch to remote (or vice versa) is propagated correctly on the whole system.

Is there a solution for this?

Thanks!


(Robin) #2

Direct association between Z wave groups is possible but I have never seen this done with Smartthings.

The Fibaro home centre and Vera can do it.

The following thread may be of use to you:


#3

@RobinWinbourne
I am planning on using a remote, not a set of switches controlling each other. If I used switches, I would just wire the three-way in using GE’s product (z-wave switch plus add-on). I was hoping for a battery powered remote and 1 switch.


(Robin) #4

Ok

Here is a list of all devices confirmed to work locally (without Internet connection). You will need to select a switch and a remote from the list:

You can link devices that allow local processing using the ST Smart Lighting app (the only app that can run locally)


#5

So, to be clear. I could buy any device that would work as a Z-wave switch in smartthings, and then buy the aeon minimote or a z-wave remote, and use the ST smart lighting app to link them and it will then work if the hub is unavailable?

I would setup all the linkage through smartthings, correct?

Any recommendations on a good z-wave switch that will be recognized as that device handler (verses a different one)


(Robin) #6

The hub has to be available at all times for local processing to work.

Local processing works when the ST cloud or internet is down.

Both the switch and the remote will need to be compatable with local processing… Suitable devices in the link I posted above.


#7

Unfortunately, no. I’m very tired this morning and I will not be able to answer follow up questions , so others will have to help you. But the main answer is:

One) the official smartlighting feature still requires that the hub be working. It just doesn’t always require that the SmartThings cloud be available by Internet, as long as the only devices being a rule are eligible to “run locally.”

  1. zwave association is an optional feature of the standard, and is up to each manufacturer to decide model by model whether a device will support association or not. So you have to check the device specifications at the official zwave alliance site for any model that you are considering.

http://products.z-wavealliance.org

  1. if the device supports association, you will need a minimote, which is a small handheld remote, to do the association. It can either associate things to itself or associates to other devices together. Unlike many other Z wave controllers, the smartthings hub does not provide a way to do associations without the minimote. You can also use the minimote as a handheld remote on your network as well if you like. Creating The initial association is a special one-time administrative function.

If you shop around you should be able to find a minimote for about $25.

  1. The two devices to be associated must both be zwave, must both support Association, and must live within about 40 feet of each other. The signal does go through walls, so around the corner in the hallway typically works. But not at opposite ends of the house. Zwave plus has a noticeably longer range then classic Z wave, so probably up to 60 feet in a typical US house.

You will not be able to use any of the other rules and logic from SmartThings without the hub. For this set up you are just using a feature of the Z wave standard, but again it is an optional feature, so it won’t work with every device.

It won’t matter whether the second device is a handheld remote, a battery operated switch that goes on the wall, another wired switch, or even a motion sensor as long as the other conditions are fulfilled.

To summarize:

One) two Z wave devices, each supporting association
2) The devices live within about 40 feet of each other

Three) you create the initial association using a minimote

Once you have that set up, you could sell your hub and the association would still work. It’s the two devices talking directly to each other. But only over a short distance, only for basic on/off, and only if the conditions Above we’re met.


#8

@RobinWinbourne is fairly new to SmartThings and lives in the UK. He is very knowledgeable about the use of in wall micro relays as he has done his whole house that way, but there are very few wall switches available for use in the UK with SmartThings, so I’m not surprised if he hasn’t heard of the use of association on the SmartThings platform before.

That said, it is very frequently used in the US, where we have a wide variety of switches, including some which are specifically designed for the use of association to create a virtual three-way between two powered wall switches. In this case, no traveler wires are needed. Several of the most popular switch brands in the US rely on zwave Association for their three ways, including GoControl, Cooper, and Leviton. So you will find many forum discussions about it.

In particular, linear/go control (which are not available in the UK) make a very popular three-way set. Both switches are wired to mains power, but they do not use physical wires to communicate to each other. Instead, they use association to make a wireless connection between the master and the auxiliary.

We even have an FAQ on how to set up this association:

One of the unusual things about smartthings is that it also allows you to set up the equivalent of an association but between any two devices that your hub can talk to, including devices of different protocols or very far away from each other. That’s what the official smartlighting feature can do, Among other things. However, that method does require that the hub be operational as it is acting as the “man in the middle.”

And many community members are using both methods, relying on Z wave association for devices which meet the criteria I listed above so that they will continue to be operational even if the hub is out, and relying on the hub and the smart lighting feature, or other smartapps, for everyday cases that don’t meet those criteria.

(The GE switches, another popular brand, do use physical traveler wires, so again, you just have to check each model that you’re considering.)


#9

I also wanted to mention that the smartthings hub doesn’t use Wi-Fi at all. It contains a Z wave controller and a zigbee coordinator and communicates directly with the devices in your home that way. And it uses a direct cable to connect to your ethernet router and reach the SmartThings cloud.

So if your Internet is available to the hub via ethernet connection but your Wi-Fi router is out, it won’t affect the hub unless you have devices like WeMo we specifically use wi-Fi for their own device communications.

On the other hand, if the Internet is not available or the SmartThings cloud is not available, then The V2 hub (the current model) can use “local processing” which you will see discussed in many forum threads.

Local processing on SmartThings is extremely limited. Most of the code runs in the cloud, including routines, smart apps, even the ability to arm or disarm smart home monitor. And the smartthings app on your mobile phone cannot talk to the hub unless the cloud is available even if they are both on the same local network.

But there is one important exception, which is the official smart lighting feature. That can continue to run as long as all of the devices in the smart lighting rule are eligible to “run locally”. It’s a pretty limited feature set, but it does mean that if you have a motion sensor set up to trigger a light coming on, as long as the hub is still operating that can probably still work even if your Internet is out for the smart things cloud is down. And it will work even if the sensor uses zigbee and the light switch uses zwave, because the hub will act as a “man in the middle.” So the sensor would talk to the hub, and the hub would tell the light to come on.

And again, it wouldn’t matter if the Wi-Fi router wasn’t working, because the hub uses its own radios to talk to zwave and zigbee devices.

I know that’s a very technical answer, but because smart things is a multi protocol platform, the issue is always much bigger than just “Wi-Fi”, sometimes in a way which is good for the customer, and sometimes in a way which isn’t.

I hope all that was clear, as I mentioned, I’m tired this morning. :sunglasses:


(Robin) #10

@JDRoberts has been on ST since time began, he has become stubborn and stuck up, and considers himself the only person who can answer anything!! He takes great joy in putting others down!!

Actually I have several Fibaro’s directly associated with each other… The feature is available on numerous devices in the UK.

I am aware the ST Hub cannot setup direct associations between devices, it’s a PIA!

I have always used a friends Fibaro hub to do this but it’s handy to know that the minimote can do it as well.

The OP does not want to use an add on switch… He wants a battery remote at the secondary position. Using locally capable devices in conjunction with smart lighting was therefore a sound reccomendation.


#11

I was responding to this. I’m not surprised if you haven’t seen it done in the UK, but it is how many light switches are designed to work in the US.

And Cooper makes a battery powered add on switch which looks exactly like their regular wired switch and is very popular in the US for that reason. It would fit the criteria in the original post.

Lastly, I am always happy whenever anyone else participates in the discussions in anyway, either with questions or answers. But I am an engineer, and like most engineers, the details matter a great deal to me. I know that can drive other people crazy, and I apologize if you felt any distress over my post. That was certainly not my intention, so obviously I expressed myself poorly.

Submitted with respect.


(Robin) #12

I have never seen ST setup a direct association between two devices… Have you?

It is done by the devices themselves (in the case of add on switches) or different hubs / minimote.

EDIT (2/May/17): We now have device handlers like zwave tweaker which can setup direct association between zwave plus devices which support association… all is good in the world!!


#13

Yes, I have, and that method is one of several documented in the FAQ I linked to. It can be done using the setassociation command. But it requires custom code and it’s more work than it’s worth in most cases since you can just use a minimote instead.

Under the Z wave standard, it cannot be done by the devices themselves, it requires the participation of a controller. But the minimote can act as a secondary controller, which is why you can use it for devices which are on a SmartThings network. :sunglasses:

edited to update: as of March 17, a community member, @zcapr17 , has created a new way of doing associations with SmartThings which is now pretty easy. They created a device type handler called the “Z wave tweaker.” You just temporarily assign that to your Z wave device, then you can use the tweaker to set associations and configure parameters, and when you’re done you assign the device back to your everyday device type handler. Very useful! :sunglasses:


#14

Thank you everyone, and especially @JDRoberts for the assistance.

I think you have answered my question. If I can run the lighting locally, that is really all I need. Basically, my wife wants the light switch to work when the main power is out (we are running on a generator) and so internet is out but the electricity is working.

As long as the Cooper battery powered switch can count as a “Z-wave remote” in Smartthings and be locally run, I am good to go.

One last question. On the link to the Z-wave devices, its the presence of association capabilities that I am looking for when assessing which devices can do associations (if I want that feature), correct?

Thank you again for all the help.


#15

The Cooper is one of those devices which can drive you crazy. It can operate locally through direct zwave association even if the smart things hub is missing altogether once the original association is set up.

However…It cannot “run locally” in the SmartThings environment because it requires a custom device type handler.

So you would be in a situation where pressing on the auxiliary switch on the wall would send a direct message to the master switch which was controlling to load to the light fixture and the light would come on even if the Internet was not available. But the switch would be invisible to the official smart lighting feature if the Internet was out because it has a custom device type handler.

I know that’s tedious and confusing and I apologize for that, it’s just the way SmartThings works. It was originally a cloud-based system, and then they stapled a little bit of local processing onto it. But they are philosophically absolutely committed to being a multiprotocol system, which is a good thing, but it means they don’t always expose features (like Association) which are only available with some protocols.

So lots of US members in the community are using the Cooper switches and really like them, and it does mean that the auxiliary still works when SmartThings is being flaky, just as the brands that use physical travel wires still work, but it’s not working through the official smartlighting feature. It’s working through Z wave association, which, to be honest, SmartThings kind of likes to pretend doesn’t exist because you can’t use it to associate a zigbee device to a Z wave device and they want everything to be protocol-neutral.

If you want to use the official smart lighting feature and the local processing that is available through SmartThings, you need a device which can use the generic Z wave switch device type handler. And to be honest I’m not sure if that works with the Cooper battery model or not.

@lgkahn might know, he ended up writing his own device type handler for the Cooper, but I know he’s done a lot with those switches and he might know if they could use the generic handler and operate with the local processing feature of SmartLighting.

But in the SmartThings environment, it’s two different questions. 1) Will the add on switch work if the smartthings hub is running SmartLighting locally and the Internet is not available and two) will the add on switch work if The SmartThings hub itself is not functioning.

There are some devices where the answer to the second question is yes but the answer to the first question is no. I think the Cooper 9540 might be one of those, but as I say I’m not 100% sure.

Note that even if it is one of those, the Cooper battery switch would work with smart lighting just fine if the Internet was up. And you could set things up so that it was using smart lighting with a custom device type handler when the smartthings cloud was available, and relying on Z wave association when The SmartThings cloud was not available. I think quite a few people use it that way.


#16

Yes, exactly. :sunglasses:


#17

I’m with you on most of the technical aspects, with one follow-up question, assuming I can’t use a generic handler with local processing. Say I buy the Cooper device, a standard Z-wave switch (that supports association), and minimote. I setup the direct association. I then get the smartthings hub and and my z-wave switch to it, so I can control those lights from my phone, turn on when garage opens, etc. Given my slaved Cooper device, if I activate it to toggle the Z-wave switch, will smartthings know the switch has been toggled (and thus reflect the change in on/off status), even if Cooper the switch isn’t on the smartthings environment?

If not, is there a Cooper-like device that is compatible with the local processing of smartthings?


#18

The cooper will have to be on your same smartthings network or the Z wave association won’t work. So it would be known to smartthings, it just might not be known as a device which can “run locally” if the Internet isn’t available.

A Z wave device can only have one primary controller, so both the master and the auxiliary have to recognize smartthings as that. Otherwise they’ll ignore each other.

As far as status updates, that’s kind of a long conversation and I’m just not up to it right now. Hopefully somebody else will answer. But if you’re using Association, the smartthings hub puts itself into the Association group by default, so you’re usually fine there. It will get told when the auxiliary sends the command because it’s in the same Association group.


#19

So my work flow would be to buy the hub, switch, Cooper remote, and minimote, and then:

  1. use minimote to associate Cooper and switch (not sure how that’s done but I can read up on it)
  2. add cooper and switch to smartthings hub.

The cooper might not work in “local mode” but because I made an association, it will still work if the hub is down in any way, since I set that up.

That the summary?


#20

You have to do two before one. All the devices (master, auxiliary, and Minimote) have to already belong to the same network, in this case the one where the smartthings hub is the primary, in order for the association to work correctly and the devices to also be available to SmartThings. For one thing, with Z wave devices it is the primary controller that assigns the network ID to each device, so they need to have gotten their network ID already. But other than that, yes. :sunglasses: