Hi all, total newbie to home automation but spent the last few days looking at various lights and I was wondering if anyne can help me with their experience:
I understand that a big limitation of RF is that there is no reply to commands sent so there is no way to know the status of a device ie is my light really on or off? Some devices like GLS switches working by sending ON only messages and OFF only messages so at least you can assume a message won’t change the state of a device if it’s already in that state (idempotent). But the Livolo switches use a toggle message so you really have no idea at all if a light is on or off.
This seems to me like it would cause major issues wheres with a z-wave device like the Fibaro dimmer it uses a mesh network and can accurately report the status of a device and is therefore far more reliable. Does anyone have any real world experience with these devices and can comment on whether this is how it really is?
I’m not really sure what you are comparing. Z-Wave is an RF system Some RF systems have 2 way communications, some don’t…
Note that while the technology may allow status reporting, up until 2016 there was a patent that precluded z-wave devices (such as switches, dimmers, etc.) from reporting “instant status”. Hence, devices needed to be polled to determine their status. My facts may be a little fuzzy, but I believe Lutron owned the patent, and that Leviton and maybe one other company were the only z-wave device manufacturers that licensed the patent. Leviton had devices that included instant status, however, they were priced considerably higher than the devices that didn’t have instant status.
Of course, it’s less of an issue now that the patent has expired. New devices are not constrained in this way, but there are still lots of older devices on the market that have this limitation.
fair point, I was referring to the typical 433Mhz rf devices. None of which I have seen have 2 way communication.
I would agree on this point. I used some before switching to Z-Wave and would recommend avoiding those with one way comms - it’s just not very reliable.
great info, thanks, even with the necessity to poll the device though at least you can actually enquire the state of the device. Some of the devices I’ve seen appear to only have an rf receiver so you can’t get the device status. I have no idea how you could control that in an automation system! I was thinking about getting some Livolo switches (I’m in Europe) but the lack of status really put me off. I’m thinking now of getting some standard switches and buying Fibaro z-wave dimmers to automate them even though they are much more expensive.
Thanks for the advice Chris, that’s what I was afraid of.
I have 3 zwave lights that report thier status in real time. They are switched on and off from a Pi3. As a non-programmer it was a lot of work setting up and getting it to work but once it did, it has never failed.
I bought everything on Amazon and ebay.
I’ve also just started with my home automation, but so far I use a mix of z-wave and 433MHz. I use z-wave for wall switches and other things where I need to know the status of the lights. But since 433MHz switches are a lot cheaper I use them for less important things, like plug-in switches for my window lights.
Seems a waste of money to buy 10 z-wave switches for 50€ a piece when a 433MHz switch sells in packs of three for 35€. I haven’t had any problems with lights not turning on yet, and should it fail it’s no big deal in this case.
One thing to concern is also the security. Those cheap/simple one way 433MHz devices can be control by anyone, also your neighbor or anyone near by. Z-Wave devices support encryption (AES).
In addition to the good points made already, I own a couple of (old) KaKu/CoCo switches and dimmers, as well as a sunscreen controller (somfy). I integrated them in openHAB using the well known rfxtrx433 box. They are operating extremely reliable, When I am at home and can check things, they literally always work, flawlessly.
However, I did have some failures due to openHAB itself, more specifically the astro-binding regularly failing (see the appropriate threads, solved in the 2.2-snapshot). If this is really important, with 2 way traffic you could lmaybe set up a rule for checking (but hey, if rules do not trigger at all, it still does not work)
That being said, despite the proven reliability I am still not happy for the fact that the status can not be checked. I am reluctant to trust them in a situation where I am not at home (holidays mainly). It seems a mental thing, and you have to decide for yourself if the extra money for 2-way traffic is worth it for you.