Should I Reconsider Z-Wave?


Senior Member
I don't want to clutter up the Fibaro thread but it got me thinking about the reasons I have rejected using Z-Wave in the past and wondering if things have improved to where it might now be a viable option for me? Maybe a Z-Wave user can help me overcome some old misconceptions.
Capacity - As somebody who frequently maxes out the link capacity of my Insteon PLM and wishes Elk would expand their zone capacity beyond 208, I am concerned about a hard limit of 232 devices. It sounds like that would be OK for a lighting only protocol but if you are doing lighting, sensors, fire/security, locks, etc. it just doesn't seem like enough scalability to cover everything. I know Homeseer can manage up to 4 separate Z-Wave networks but is that typical of other controllers like Fibaro etc.?
RF Only - While 900 MHz does have good penetration I worry that RF just won't work in older buildings like my house. I need 4 APs just to ensure Wi-Fi coverage in all of the dead spots created by chimneys and stone walls so am skeptical about low power RF that is limited to 4 hops. My walls are plaster and lathe or stone. All electrical boxes are metal and fed by conduit or BX. The only way for RF to enter or leave a switch is through the front and depending on the size of the grounded switch frame that might be a very small window.
Routed vs. Broadcast - With broadcast technologies like Insteon all I have to worry about is ensuring that I have sufficient signal strength for the command to get through. With routing it seems like the potential exists for things to get screwed up any time you re-arrange the furniture and lamp modules move etc. It also seems like it would further complicate adding or replacing devices since that would potentially change the optimal routes of the whole system. Things change often in my house so how much of an issue would this be?
Status and Local Change Reporting - A large percentage of my switches are not just remotely controlled but are also used to trigger other actions. When I last looked at Z-Wave it was not good at reporting local operation... has that changed? Also I struggle with keeping my controller in sync with the actual state of devices so I query devices regularly to ensure the two are in agreement. Do Z-Wave controllers have an option to query devices to confirm their current state is reflected accurately in the controller table?
Are my concerns out of date or are these still valid issues for a house like mine?
I'd like to address what I can:
If your house can be covered by 4 AP's, I wouldn't be so concerned about the range of the devices.In general though, I'm not a big fan of mesh networks because of the latency between hops.
As far as capacity goes, this is kind of the point of central automation hub, to aggregate what would otherwise be segregated systems. With a low enough latency and response time, this should be a near perfect solution. I'm from the Elan world so I can really only speak for that, but reaction between segregated systems just seem so instant you would never even know.
I prefer anything routed to broadcast because of the reliability and lowered latency when system size is increased.
I too have had problems with Z-wave devices reporting status change, and have also had problems with queries going unanswered, and answered intermittently.
I'm not really an huge fan of Z-wave. For lighting I use RA2, climate Aprilaire, Security Elk or GE, etc. Each one of these devices uses their own protocols, but they seem to be the best at that one particular task. Integration, triggers, anything else is all done through the system hub.
From the devices I have seen, any ZWave devices that perform close to Insteon quality  cost a fair bit more. I don't feel there is enough reason to change technologies, yet. Time will tell.
Insteon doesn't require all the extra paraphernalia that Zwave does and when you purchase a device you know it should be compatible with any Insteon system, unlike many Zwave devices,
I have the same concerns and from the recent threads on Zwave I don't see it up to snuff just yet.
Thanks both for the feedback. Every once in awhile I see all the nifty Z-Wave devices from Fibaro and others and it makes me want to give Z-Wave another chance but it never pans out. If I ever decide I need to leave Insteon it will probably be for RA2 but nothing really is compelling enough at this point to justify a change.
If I didn't already own a ton of zWave i'd absolutely move to RA2. zWave is too hinky.
Routed vs. broadcast: on a z-wave network, any time you change something, you can 'optimize' the network (which fixes routing problems).
Reporting: I read last year (I believe from Homeseer) that things in this department will improve. The patent on 'instant status update' ran out (or will this year?). So, now everyone can implement that feature.
Did you consider UPB?
I'm not familiar with Insteon or Elk, so I don't know what technology they use.
Yes I did look at UPB. Two challenges for me were the delay while waiting for a double tap and physical size of the devices which make them unfriendly in retrofit for very old homes.
For Z-Wave I still need some assurance they will work well in grounded metal switchboxes with stainless steel or brass switch covers. Seems like an RF only protocol is just not going to perform well in retrofit "old work" electrical systems.
What is this UPB delay you speak of?  I used to think I had some delay with scenes in UPB, but it ended up being a function of setting lights to ramp on from 0 to XXX over yyy seconds.  If was more of a perception since the lights ramped from zero.  If you set them to either "snap" on or ramp over a shorter period, the response is near instantaneous.
I use the double tap extensively.  Single tap turns on any single load, but double tap turns on a group within a room.  
Here in the midwest my concerns were similar to yours UpstateMike relating to metal boxes and metal conduit.
I have no issues today with UPB and do not tinker with wireless switches inside of metal boxes.
All of my current UPB in wall switches utilize single and double taps with no issues.
Are my concerns out of date or are these still valid issues for a house like mine?
Here old fashioned a have built new wanting copper plumbing and conduit (paying extra) connecting metal boxes and really dislike romex for electric.
That is me.
That said whatever you decide personally you will make work from what I have read above.
With the advent of Z-Wave Plus technology a few years ago, Z-Wave performance and reliability improved dramatically. If you browse our forums, you won't find a lot of chatter about Z-Wave problems now... at least not nearly as much as a few years back. FWIW, we support *multiple* Z-Wave networks. There is no "4" network limit.. not sure where that number came from? Also, in February of 2016, the patent on instant status reporting expired. A month later, we release our 100 series Z-Wave lighting products with instant status and multi-tap features. Our new 200 series switches have been out for about 2 months. Those add controllable RGB LED indicators to the mix along with multi-tap trigger operation up to 5-taps.
No, most other controllers do not support multiple Z-Wave networks. Vera allows you to use multiple controllers but they are not centrally managed. 
Regarding performance under difficult conditions... my house was built in 1950 and is full of small metal electrical boxes and very thick plaster walls. I have 30 line powered Z-Wave devices and another 10 are battery operated sensors. Most devices are Z-Wave Plus (with v6.5x ZDK). However, there are still a handful of older devices (with v4.5x ZDK). The ONLY problem device is my older Yale door lock and I'm going to upgrade the Z-Wave module to Z-Wave Plus in a week or so. That should fix that. Everything else is rock solid.
Bottom line: Z-Wave is a much better technology today than it was 5 years ago when we released HS3. I would say it's definitely worth a second look.
I'm starting to dabble in Z-Wave and currently have 20 devices, mostly switches and a few door/window sensors.  I have switches from three different vendors (just to try them out) and they are all Z-Wave Plus.
All switches and devices work well with HomeSeer, which was my main objective now that I'm using their HomeTroller Zee S2.
I know it's a different animal, but I just couldn't go back to a power-line technology after dealing with X-10 (yes, I know UPB is different in this respect).  I also like the fact that you can easily find a variety of products compatible with Z-Wave beyond the light switch (door/window sensors, smoke detectors (just ordered two of these), status indicators, etc...).
I'm hoping to make it to ISC West 2018 in Las Vegas and will visit the Z-Wave partners booth, so hopefully I'll come back with the latest and greatest info out there for new devices!
I thought I read the Z-Net interface was limited to a maximum of 4 on a network when it was introduced? Maybe I'm misremembering. It is good to hear of somebody using Z-Wave with metal boxes and thick plaster walls but I still don't see how the signal gets out of the switchbox? The switch frames are metal and bonded to the grounded metal switchbox so essentially trying to transmit and receive from within a faraday cage. So how can this work at all let alone well?
I do like the look of the new Homeseer switches and being someone who is more interested in being alerted/informed by my automation system than controlling things with it I could see me using the heck out of the colored LEDs. I just can't get my head around how this would work... especially in the basement where most of the switches are in those surface mount waterproof boxes mounted to the fieldstone walls and fed via grounded conduit. How the heck can Z-Wave penetrate that?
The Z-Wave antenna is positioned immediately behind the paddle on every wall switch. This allows the signal to propagate from the front of the switch out. So the RF pattern is approximately 180 degrees for each switch. That provides quite a bit of coverage.
macromark said:
The Z-Wave antenna is positioned immediately behind the paddle on every wall switch. This allows the signal to propagate from the front of the switch out. So the RF pattern is approximately 180 degrees for each switch. That provides quite a bit of coverage.
Thanks. That was what I was having trouble picturing. Maybe Z-Wave is a possibility for me then.
upstatemike said:
Thanks. That was what I was having trouble picturing. Maybe Z-Wave is a possibility for me then.
A lot of this answer depends on what your budget is really.  In my case, I went with a Homeseer switches for my entire house, ended up with ~75 of them installed.  It's been OK, but it feels like I'm constantly trying to track down a device with an issue that will crap on my entire network.  It's not uncommon for there to be a 3 second delay on a motion sensor light walking into a room - for me, it's probably 50/50 on if that light will turn on instantly or if it will respond in 3-5 seconds, which is aggravating.  This is why I'm switching to RadioRA2.  It was a technology I considered originally when I built, but couldnt stomach the cost of it.  Now, I've learned my lesson: buy nice or buy twice. 
Bottom line is if you have a small network, I think zwave is terrific.  I'd say once I got above 60 devices, things started to go south.