Range in a Large Home


(Douglas L) #1

First, sincere apologies if I missed the answer somewhere here; I promised I looked first.

I have a big home and over 50 devices (mostly light switches) connected. I am on the Classic App (haven’t been invited to the new one and nervous about all that, anyway. I have a v2 hub.

Problem is that I can’t seem to get some (and only some) switches that are far from the hub to reflect their proper state. I put in three Aotec extenders ad that helped a bit, but not with all the switches. Hub is up on second floor - problem switches are in basement. I have tried repairing the Z-Wave Network on multiple occasions. Is there a better solution to ensuring a high quality, reliable z-wave network? Are the Home Connect Pro (3 pack) the answer?

Sincere thanks in advance!


(jeubanks) #2

A few things to check.

  1. Are all of your powered devices Z-Wave Plus? If not that could be a limiting factor of network reliability and range

  2. A Z-Wave Optimize sometimes is needed more than once. Sometimes multiple times to optimize the neighbor maps then to optimize the return routes. SmartThings doesn’t give a choice so it’s a full optimize each time which will take a while.

  3. The Connect system is a WiFi Mesh it does nothing to expand your Z-Wave or ZigBee Mesh’s (someone will correct me if I’m wrong)

Another issue is that Z-Wave has a 4 hop maximum for it’s routing. So any device that is more than 4 hops from the controller is going to be problematic as a lot of the times it will just fail to respond and sometimes it will respond and that’s because in time devices will “adjust” their own routing tables trying to “self-optimize”.

Once you get to the point of more than 4 hops it’s time to start thinking about another system with multiple controller capabilities.


#3

Basements are almost always a problem, just like garages, because there tend to be a lot of architectural barriers. Metal, concrete, large metal objects like refrigerators or washing machines, sometimes different kinds of insulation in the walls, water pipes running through the ceiling – – all of it can cause a problem.

The single purpose range extenders are not worth the money: they were useful a few years ago when not all Z wave devices operated at full power, but now pretty much everything does. So you can use most mains powered zwave devices including a light switch or a plug-in pocket socket or even a Z wave light bulb and it will do the same kind of repeating that the single purpose device does. Just make sure its zwave plus to get the most range out of it.

I mention the lightbulbs because those are a popular repeater for the basement because you can often bounce signal down the stairwell using a lightbulb when there isn’t any other place to put a repeater in that area. So that’s just something to keep in mind. Get one that is zwave plus.

The other question, of course is if you’ve run out of hops. Where is the hub located?

(The new Wi-Fi mesh hub models do each act as a Z wave repeater, but again they don’t give you anything more than another Z wave repeating device in the same location would. They are more important as far as eliminating Wi-Fi dead spots. )

It sounds like you’ve probably already read the FAQ on whole house coverage, but for anybody else new coming into this thread, I’ll put that here. (This is a clickable link)

Just speaking as a field tech, I’d start out by assuming that it’s hard to get signal into the basement. It’s easy to test that. Take a battery powered Z wave sensor and put it right outside the door to the basement, but on the first floor side, run a zwave repair, and check and make sure it’s working.

Assuming that looks good, now move it to just inside the stairwell to the basement with the door closed, run a zwave repair, and see if you still have communication.

If that’s good, then go down to the base of the stairs and put the sensor there and repeat the process. If you lose the signal at that point, then we got to get a repeater between the top of the stairs and the bottom of the stairs which almost always means a lightbulb, but could be a light switch or maybe a plug-in pocket socket.

( if just closing the door and putting the sensor on the other side of it cuts off communications, you got a different kind of problem and you’ll have to address it like it was an outbuilding.

http://thingsthataresmart.wiki/index.php?title=How_to_Automate_an_Outbuilding )

Once you have a good connection to the base of the stairs, probably all you need is any repeater right in that area, and it should then be able to get signal to most of the rest of the room unless you’ve got a bunch of appliances and stuff.

So sometimes this process is just trial and error, but start out by assuming that the floor is difficult to get signal through and then see what else you can do. :sunglasses:


(Douglas L) #4

Many thanks. I put most of my switches in 3 years ago. They are GE and I don’t think any are Z-wave plus. I will look into finding a way to spread some of those in. Are there plus switches people favor?

Am also curious about what options exist for systems that have multiple controller hubs.


(jeubanks) #5

Unfortunately with a z-wave vs z-wave Plus it’s best to be all or none. Z-Wave performance is limited by the lowest common denominator in the mesh.

If you have 1 large mesh and 90% are z-wave Plus devices but that little 10% is older z-wave then the entire mesh is going to run at the performance of the older z-wave. Which in general is not horrible but you lose any benefit of Z-Wave Plus in a mixed environment.

With a multi-controller setup you can try and isolate the Plus and Non-Plus devices so they don’t interfere by going with a multi-master (multiple primary) configuration (multiple z-wave networks). The downside is the mesh is only as strong (range) as it’s isolation partners. You would have multiple small mesh setups.

Then there’s a multi-controller (primary/secondary) setup where everything is still on the same network but you can have multiple controllers to extend the range and hops. The Z-Wave vs Z-Wave Plus rules still apply and the network is only as fast as the weakest link. Each controller is independent but still part of the same network.

SmartThings does support including a “secondary” controller, but I don’t know if it is a “Secondary Inclusion” controller setup or if it’s a masked multiple primary setup. Someone else will have to fill in the SmartThings specific details as I never got this far with using SmartThings and it is not an “advertised” ability and I’m not sure if it’s even supported.

There are many systems that will support either a multiple primary or primary/secondary setup. As this is the SmartThings forum I won’t advertise the competition.


#6

Do you have a source from the Z wave alliance for that? Because respectfully, that’s not how it works. Each individual device is limited by its own range, but it’s not affecting range of any other device. And as long as the controller is Z wave plus, any path along zwave plus devices to it will be able to take full advantage of zwave plus features, even if there are other Z wave classic devices on the network.

The zwave standard has always required being backwards compatible, but that doesn’t mean that the newer generation devices get slowed down to the speed and range of the older ones.

Imagine a network with the hub, a zwave plus switch in the entry way, a zwave classic switch in the kitchen, a zwave plus motion sensor in the basement, and the hub one floor up in the hallway with a zwave classic sensor there as well.

The classic kitchen switch is too far away to reach the hub or the classic sensor upstairs. But it can reach the entry way switch and it can reach the basement sensor.

The entryway switch can reach the hub upstairs, but it can’t reach the basement sensor.

Now imagine you have a delivery service where some parts of the routes are handled by van (zwave plus) and some are handled by bicycle (zwave Classic).

We want to get a message from the basement sensor to the hub.

So it starts out with a van, which covers the distance to the kitchen switch. At that point the message is given to a bicycle rider, who delivers it to the entry way switch. That’s zwave plus, so we go back to a van, which delivers it to the hub.

Only the part of the route which was transmitted by a zwave classic device is limited to Z wave classic range and speed. It doesn’t in any way change how fast or how far a different switch can transmit.

Now imagine we are sending a message back from the hub to the basement sensor.

Again, it goes by van to the entryway, but then it also goes by van to the kitchen switch, because it is the Z wave plus switch which is transmitting. So a message travels faster in one direction than the other, because the limit (which again, only applies to that 1 hop) is based on the device doing the transmitting, not the device which received it.

OK now let’s look at a different route.

Suppose there is another Z wave plus switch in the dining room, and it can reach the entryway switch. It can’t reach the hub directly.

When the dining room sends a message to the hub, it goes by van to the entryway and then by van to the hub. Full zwave plus speed all the way. It is not in any way slowed down just because there happens to be a zwave classic switch in the kitchen.

So mix and match all you like. That’s one of the design intentions of Z wave, that people do not have to replace older generation devices unless they specifically need the features that come with a newer generation.

The older devices will only slow down the specific hopfor an individual message, and only if they are the transmitter of the message for that hop. Which is a good thing when you’ve invested a lot of money in devices which worked just fine the way they are set up. :sunglasses:


(jeubanks) #7

@JDRoberts

I suppose I should have been more clear in the statement. Let me see if I can clarify what I was getting at.

The range in specific is affected by the range of the non plus device in the mixture.

plus -> plus -> non-plus -> plus -> non-plus

The range between the non plus to the next plus device will become an issue. Having them inter-mixed can be intermittent with the range quality. This inter-mix of devices also limits the speed of communications to the lowest common denominator of neighbors.

Z-Wave Plus is backwards compatible which means it will slow down to account for the neighbor speed. This also means the advanced routing/discovery/beaming features of Z-Wave Plus will not be used.

Now there are different discussions that have gone on with varying information. I don’t have direct access (yet) to Silicon Labs specifications so I can’t say with any assurance. However if you search around other forums it would seem that having older non plus devices does have a more significant impact on the overall health/performance of a larger network inter-mixed with z-wave plus devices. This impact manifests in different ways from being “lag” to “reliability”.


#8

I was a network engineer and worked with Z wave professionally before I ever got a SmartThings device, and had access to the materials which required at that time the $3000 a year developer license, and took those training courses.

I’ve never heard any professional network engineers or anyone from the Z wave alliance say there was a problem with mixing zwave plus and older generation devices On a network with a zwave plus coordinator with the exception of the single hop involving 1 zwave classic and 1 zwave plus device except for the transmission of that single message over that single hop when you would be limited to the zwave classic capabilities.

It should not introduce anything else negative to the network as a whole. That’s pretty much the point, as they definitely did not want people to feel they had to replace their older devices.

Now if the controller (hub) is an older generation, then indeed the entire network is devolved to that level. So perhaps that’s what you read.


(jeubanks) #9

Piece by piece.

Older hub. yes bad news in general I think (opinion).

I thought I was a bit clearer that it’s the hop to hop that becomes the issue in a larger network of just causing a general slow down if you have lots of hops. If you don’t have many hops then it’s not an issue.

Well I’m not a network engineer but I am a systems engineer and have been for many years as well. So I think we have adequate coverage there :slight_smile:

I currently don’t have access to the z-wave specs but I’m planning on it. However we both know from experience that vendors even with paid access don’t disclose all issues even if they are known or widespread. that’s what forums are for :slight_smile:

I agree in “general” this is not a problem and should not cause an issue. This was all in reference of a “large” network with many hops. Lets just say this is all “my opinion” based off of readings of others experiences and my own with having mixed devices and a lot of hops and seeing “irregularities” between device behaviors. Should it happen based on the specification? no… does it… well as they say your mileage may vary.


(jeubanks) #10

Not to completely derail this @JDRoberts, what what are your thoughts in this regard? This is more of a question than statement.

Z-Wave Plus is a protocol standard which also means it has been deployed on 300 and 500 series chips. The 300 series chips have a limit of 40kbs where as 500 series can do up to 100kbs and still concurrently listen for the lower speeds. There are the older than 300 series and the 400 which are rare to encounter anymore but I wouldn’t doubt there are still devices out there.

I’m just rambling about the 300/500 at the moment…

The range between 300/500 series is also different.

What could? be the havoc of a 300 series chip with ZWP intermixed with even older series ZW and newer 500 series ZWP devices?

Due to the range of the chips this could? affect the routing table at random times depending on how/when/where it was set. The route is defined/set during an Optimize, however the protocol can and does “update” the route through the explorer frame requests when needed. So it is possible for a network to get “out of whack” if devices are not communicating based upon range issues/differences in chipset limitations and not necessarily if they are ZW or ZWP.

Now from my understanding most 300 series are just ZW but some may be ZWP and just limited. Could this intermix of chipset capability along with protocol capabilities be causing more issues than what we normally think about?

Just random thoughts really but I like these conversations with @JDRoberts


#11

Why don’t you start a new thread about zwave protocols under devices and integrations ? :sunglasses: Then we can go into more detail.

But the short answer is that as far as I know, zwave plus is only commercially available on the 500 chip series-- it’s just the marketing name for the fifth generation.

Do you have an example of a 300 series chip commercially available device with zwave plus?

Also: I think you’re not quite used to thinking in terms of mesh networks yet, because the kind of problems you describe are what would occur in a star topology. Not mesh. In particular, it is not true that the routes are fixed at the time of optimize. Those findings are just given to the device as a shortcut, something to try first if available. Also, that’s not how the explorer frames work. But again, we can discuss all that in a protocol thread.


(jeubanks) #12

I think a new thread would be of interest.

A commercially available example. No. I was going through and reading the specifications and capabilities. I also have not used/tested every single device available through amazon or gearbest or aliexpress etc etc and of course a label on a device always means it’s legitimate :slight_smile:

I didn’t say the route are “fixed” but they are set and as you said that is a “suggestion” for the device and can/does change.

Let me re-read this and see where my misunderstanding of explorer frames is when a route is not available.

http://zwavepublic.com/sites/default/files/APL13031-2%20-%20Z-Wave%20Networking%20Basics.pdf