Starting out - wired or zwave?

Hi. Just starting out. Not a pro at this stuff but learning as I go.

I recently renovated my house and I have wired the lighting circuits so that all cabling goes back to one location a din rail junction box in affect.

I am trying to find out how I may controller my lights (main house lights and LEDs strip’s) in a wired way but cannot really get anywhere?

I have played around with openhab on a RPi3 and I have a din case for it with a ZME zwave stick. I was thinking of mounting this in the large din rail junction box and fitting zwave light controllers in there but at circa £50 a go this would be an expensive option especially as each controller would only be 30cm front the Pi!!?

Any tips for starting out as I haven’t committed to any options yet?


If everything is colocated you should absolutely look at doing this wired for both cost and reliability purposes.

Now I have absolutely no experience with din rails or anything like that but suspect that all you need are some relays. though I would let someone else more knowledgeable give better advice on how to wire it up.

Maybe have a look at and look for sonoff stuff. I think this would work good for you and they are cheap and there is a binding for them.

This might be what you are looking at doing central relays and based on OH, lots of videos about how things are setup in his house.

He is working on new videos at the moment that I think will go into more details.

Thanks for the replies.

Sonoff looks good but I would like to be able to dim lights for scenes and soft on soft off. Can this be done with sonoff?

Also, I would like to be able to use the wall switches to turn the lights on and off? How is this done without using the switch to kill the power to the sonoff. In comparison, a bit like the terminals on a fibaro dimmer where you can use a rocker switch to tell it local command on /off?


Your set-up sound like ideal for KNX! I’m not sure how well integrated it is in OH though, since I don’t have it myself.
With KNX you will find all the benefits of zwave, but wired (i.e. multiple manufacturers, dimmers, actuators wall swiches etc etc). Well proven.

You might want some kind of wireless set-up as well, such as zwave etc. But that can always be added on a need basis.
This is what is great with openhab - the mix.

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KNX is extremely well integrated in OH
The only issues with KNX that I see with @antmck33 's implementation scenario is:
a) He would have to run KNX bus cables to the wall switch positions
b) The cost of actuators and push-button interfaces, etc is not small…

a) Why is this a problem?
b) I actually looked at this, some years ago, when I started with zwave, and found that there are brands that are not too expensive if you count outputs, and find a device that hosts many outputs. It does depend on how many outputs we are tallking about as well. But sure, Sonoff will be cheaper. But I’m not sure that if this is really an issue if you build a new house?

Certainly, we all have different opinions :slight_smile: and budget, but I’d say if it was me, I’d spend some extra money to have a system that does work by it self, manually from wall switches, when/if the home automation goes down for some reason.
But there are other systems as well, I just think that it is nice to start with some kind of standard, which one know will be around for the next decade.

Zwave will work, but does not really benefit from the star set-up.

Yes, this is why I am so excited to use OH… The mix and possibilities :slightly_smiling_face:

The KNX option does seem expensive …

Just clarify my setup, I have attached a pic of my junction panel. All wall switches and all lights cabling meet in this panel and at the minute they are just wired as normal switching (switched lives).


So you have live/neutral/ground routed to each switchbox, and then onwards to the lamp?
I’m not sure how you run wires in your country (UK?), are they run in pipes or just in the wall?

Either way, if you don’t want to/cannot wire anything extra, I suppose zwave in each wallbox is the simplest solution, if I got the wiring right. (And you feel that having real switches at each room is important) (which I assume).

Edit: now I saw that also the switch lead is down… :slight_smile: Then of course there are other options.

Live neutral and earth from each wall switch and live neutral and earth from each light fitting routes back to this box yes.

Whatever device I use will just replace the junction in this box for each light.

If I were to use zwave (each unit would be put in this box) it is kind of wasted as the OH transmitter is going to be housed in the box too.

I suppose I am looking for a wired solution with the simplicity of items such as zwave controllers and controllers where I can utilise the wall switch in unison with automation (IE: not just cut the power to a controller by a wall switch).


I would always go wired where possible. I’ve had the odd drop out or delay with z-wave personally.
I’m going down the c-bus route which I believe is available in the UK or I’d look at KNX. Either would need a control wire though to the switch.

Yes, my thoughts exactly which is why I wired everything back to one central point.

I also have CAT6 cabling to every location, back to a data rack, where I would want a camera, motion sensor, temp sensor, anything but it is so hard to find things that are had wired for home automation … everything is wireless WiFi or RF. It’s so annoying.

The only way it seems to have wired is for full on commercial grade equipment like c-bus or KNX or go wireless like z wave.

One question for c-bus and KNX. Do you have to have proprietary switches or “special” wall switches?

I would like to keep standard wall switches (probably rocker swiches as this would be the only way it would work in a smart sense ie not just on off switch) to keep the house Wife-friendly.


Regular (230V) switches will do just fine with KNX.
I use a 4 channel contact interface in the outlet behind the switch and it works fine
Of course, they exist (more expensive) Push-Buttons with bus inputs

I have the same situation in my house as you described: all (nearly all :wink: ) is wired back to a central point.
My clear vote goes for KNX.
First I decided for a wired installation for security reasons. Without a physical connection to the outside you don´t have to care about people hacking a wireless protocol.
Second I decided for KNX because it is rock solid. Everything configured inside the KNX system runs forever.
I did not investigate other wired systems. I don´t know c-bus, maybe it offers the same.

Over the last 7 years I did a step by step upgrade from the former relays to KNX.
Now I have:

  • 40 binary inputs (standard light switches, door/window switches) in 2 devices of 16 inputs each and one of 8 inputs.
  • One 4 way KNX bus connected switch (this is where didn´t have all wired back to the central point) connected ny one KNX cable to the central point
  • 30 binary outputs for different loads in 2 devices of 12 outputs and one of 8 outputs.
  • 9 blinds/ roof windows controlled in 2 devices
  • 4 dimmers in 1 device
  • 2 air conditions
  • 1 weather station
  • 1 electrical power meter

So, everything is set up with 14 devices + a KNX power supply + a IP gateway.
Consider: For the configuration for a KNX system you need a licence of the ETS software. A 20 devices licence was about 200€

The connection to openHAB 2.0 is stable through the KNX 1.9 binding.

The only concession I made for 2 Philips Hue bulbs because the are fancy things.

So you should check your configuration and calculate your overall cost for KNX - there are websites in Germany that has really good prices on KNX stuff. The “problem” is that it is so many devices to choose from, that it will take you some time to find the /best/most cost-effective/ devices for you.

The reason that I chose Zwave back then (~6 years ago) was that I decided that the work to pull all light fitting to a central point was a too big job, even though we have pipes in the walls/ceilings for all wires over here (.se) (My house is from -38, so it was so much easier to start with zwave).
From time to time, I am still considering to convert to KNX on occasion, but lately, zwave has been so much better with Chris’ binding, so this might never happen.

Hmm… DMX seems interesting :thinking:

With DMX, how would I be able to interface my wall switches though? Is there a way of turning the channel on and off with a hardwired switch?


Being practical I suggest that you try a few things, especially the cheaper end. There are pros and cons that you need to check out. I found the biggest issue is the light switch. I have tried sonoff and I’m about to try setting one up so that it obeys a standard light switch whilst also responding to Wifi commands via MQTT. (Openhab will talk to MQTT). I also have some Trust modules that are 433MHz wireless. You can set them up to pair with a remote wireless switch and a module will accept commands from more than one switch. The Broadlink RMpro offers a way of interfacing to the RF modules and there are ways to command the RMpro from OpenHAB. I also have Hue for a lot of lights, though there is no advantage in central wiring and in fact the inverse is better, all the lights can be on a couple of power circuits driven from a UPS. Again there is an OpenHAB interface. KNX is effectively professional quality and may be similar to some cBUS stuff I installed ten years ago. That was ideal for centralised wiring with dimmers in banks of eight and relays in banks of twelve. Lots of functionality without any external system i.e.programmable LCD switches that had text alongside buttons.

As I suggested to someone else you might do well to park OpenHAB for the time being (or rather don’t get bogged down in testing too much at once) as there can be serious frustration in attempting to make two unknowns cooperate.

Finally, consider the lights themselves because there are limitations in the choice of size, fitting and functionality, Philips Hue is seriously short on E14 and it is very difficult to read the state of lights and switches. Oh and I forgot about some switches needing a live and neutral at the switch!

Quick thing regarding C Bus vs KNX. I don’t know the KNX very well but it looks to me to be better supported in Openhab compared to C Bus. It’s just here in Australia, most electricians will know C Bus but KNX hardly exists here.

I’ve been using Openhab with cgate/cbus for a while without any issues.