[OT] ZWave

[Tim Watts]

Been playing with some of this "new" Z-Wave RF home automation stuff.

In particular, the VeraLite internet controller (runs OpenWRT inside plus some proprietary stuff), and these two devices:

(Temperature, humidity, light and PIR sensor)

(I have the 13A version) remote switch and power meter.

Certainly has some potential. I've been wanting to do a study on how much heat is needed in this house vs external temperature - plus I want to keep an eye on the humidity in the shed so my tools don't go rusty.

It's looking interesting. The main sticking point is the VeraLite is a nice piece of inexpensive hardware - but the software reeks of immaturity. I've been advised to consider downgrading to an earlier version before they broke everything.

I think, long term a Raspberry Pi with ZWave adaptor would be better, but right now, I wanted something with some functionality that "just works" - like timers to switch the remote switches for the heaters.

Anyone else played with this stuff?

[Jeremy Nicoll - news posts]

Have you read the (US) Amazon.com reviews of the various parts? It looks to me as if other users' experiences (and also references to US forums on the Vera thing) would be a good place to pick up real-life pros and cons.

I agree, and it almost looks cheap enough to buy stuff just to have a play.

[Andy Burns]

No, I do remember reading up on zigbee ages ago, but there seem to be too many competing, conceptually similar technologies, to the extent that if one of them hasn't become dominant in the last 15 years, I wonder if any of them will in the next 15?

[Tim Watts]

Well, it *seems* to be ZWave that starting to float.

You certainly can mix and match random parts made by different companies

- so they seem to have learnt a valuable lesson with all the proprietary nonsense.

[Bill Taylor]

I have a number of Z-Wave modules that is used with a program called Homeseer. AFAICS, much better then Vera, but also more expensive, and not without issues. (Vera has been going for years, so the software should be mature, but I expect they've just given up on it.)

Z-wave is OK once it's been set up and you don't change anything, but isn't as reliable as is claimed.

If a module gets disconnected or fails the network is liable to fail completely. The Aeon labs z-wave controller seems to be buggy - if z-wave message rate is too hiigh it stops responding. Some of the battery powered modules (motion sensors) have an arcane method of joining the network. When the batteries need replacing you have to reconnect them to the network; as you've forgotten how you did it the first time you spend ages tracking down the well-hidden technique.

For logging temperature/humidity I wouldn't use Z-wave. I mainly use

1-wire temperature sensors. Interfaces can be had quite cheaply and, if you're a Linux user, there are a few Linux based logging solutions. OWFS seems to be well regarded.

There are RF 1-wire devices, but they tend to be a bit pricy. Oregon wireless sensors are cheapish but you would need some sort of RF interface, which is likely to be a bit pricy. I use a rx/tx from RFXCOM which supports a lot of protocols.

[Tim Watts]

Rather the opposite - they've released so-called "UI7" formware which seems to be buggy and breaks plugin compatibility with "UI5".

I'm going to revert mine to UI5 but I have to get Vera's support to remove the "auto upgrade to UI7 flag on their database" (the damn thing is mostly stand alone, but insists on jabbering to their portal for some stuff.

The Vera Lite is a nice bit of hardware - and as it runs OpenWRT as the base to the MiOS OS I wonder if there are any open source projects targetting it...

My outside module keeps causing whines that "it's not contactable" - but I think that's more the Vera being fussy.

The power switch plug is 100% solid and sports a reassuring "click" of a relay :)

The scheduler is weak - it's edge driven, meaning if the vera goes off covering a switching cycle you are out of sync until the next one.

As it has feedback from the plug, it needs a scheduler that can ensure everying is in the right state for "now" even if it's only just booted.

I'm going to learn the scripting language as see how that goes.

[Jeremy Nicoll - news posts]

Please keep us informed!

[Tim Watts]

Certainly - I have nearly done with my plumbing. Taking the week "off" to fiddle with Vera stuff...

[Jon Connell]

Speaking of which, does anyone else have range problems with these things? I often find that my boiler hasn't come on because the thermostat is out of range. The thermostat thinks it's turned on the boiler, but it has failed to do so. So then I have to wander over to the garage, dial down the temperature and dial it back up to get them back in sync.

I could site the thermostat nearer the boiler, but that rather defeats the point of a wireless thermostat.

[Tim Watts]

What technology is the RF link in your case Jon?

Honeywell's stuff is moderately well designed - they (usually, last I read) send out repeated signals confirming the required state, so if one is missed, it merely delays the switching operation for a few minutes - which is a reasonable compromise for simplex comms.

The Zwave stuff (at least the switches) seems to be half duplex - you send the switching command then you get an ACK back if it happened. Much better design. You also get a warning if it did not get an ACK.

Is there an RF extender available for your system?

[Jon Connell]

It's a Horstmann Z-Wave thermostat. One zone works well, but the other with a different thermostat is very flaky. That does happen to be in the bit of the house with thick walls.

Are they vendor-specific, or generic to the Z-Wave protocol?

[Tim Watts]

I *believe* they are generic - but some research may be called for.

Some Z-Wave devices are supposed to be able to act as routing nodes to make the mesh stronger too.

Surprised that it is not setting up a duplex command channel - unless your signal is so weak it really can't get through...

[Andrew Gabriel]

Can you move the receiver nearer the middle of the house? (Yes, that also defeats some of the point of a wireless thermostat, although you may be able to better move it around.)

[Jon Connell]

That's an option, yes. And would be better than buying a wired thermostat. Less chasing in walls means happier Mrs.