Author Topic: Newbie planning a new home / KNX/EIB wiring considerations PLEASE HELP! ;-)  (Read 19708 times)

berlin

  • Newbie
  • *
  • Posts: 5
    • View Profile
Dear community members,

we are building a house and even my whife ("don't you dare touching my Vista-Notebook with that Linux stuff") is convinced of the awsome features and possibillities of Linux MCE. As it's too late (and too expensive ;-) ) to use complete bus system from the beginning (start of construction is in 4 weeks) I would like to prepare as much KNX/EIB wiring as possible/affordable. Therefore I kindly ask for your comments and suggestions! What we will do is CAT6 wiring into almost every single room. So at least we will have streaming media and voip everywhere.

Here is what I'm planning to do with the bus system in the final stage (maybe in 3-5 years or so):
- Controlling the inner Lights (mostly dimmable Spotlights integrated into the ceiling)
- Controlling the decentralized ventilating system integrated into the walls
- Maybe switching some power sockets as well
- Controlling the outer Lights and maybe things like a lawn sprinkler - who knows?
- maybe infrared sensors (By the way are there sensors that keep the light on even if I'm reading/working for an hour or so and realize the difference between a human and our cat?)
- a panic button to turn on all lights
- a "sleepmode button" to set the whole house to "power save mode" while nobody is at home
- and who knows what else... :-)

As mentioned above I'm planning to put a KNX/EIB wire into every wall and into the ceilings so I will have the possibillity to connect to it everywhere. I have some questions:

For later easy replacement of the standard switches by KNX/EIB switches I'm thinking of laying a bus wire directly to each button. Is that a good idea or am I completely wrong?

What kind of topology is needed? Where would you put the wires? Where the actors? I've attached a plan of our ground floor to have something to discuss about. Please feel free to paint on it where you would put which wires.



- Green X: "server room" ;-)
- RED A-C: lighting that schould be controlled separately (all of A; all of B; ...)
- Pink S: switches that are traditional switches first but should be replaced by KNX/EIB switches later.
- Blue D: Ventillation system
(of course these are only examples. Hopefully we will have light in our bath, too ;-) )

Is there a possibillity to use some kind of wireless bridge to expand the bus system into the garden and put wires from there to the actors or should I already put a bus wire through the outer wall?

I read through various german forums on KNX/EIB but the guys there didn't seem to be very helpful. The answers to similar newbie questions sounded pretty much like "We are Professionals, go read some books about it, build a complete bus house from the beginning and maybe THEN come back". That somewhat didn't satisfy me... ;-)

Please, any help would be appreciated. Plus: the better my planning is, the easyer would it be to convince my wife of new expansion stages later. She would kill me if I'd tell her in say 2-3 years "of course you can dimm the lights with that PDA but I have to open all walls and the complete ceiling to insert some kilometers of wiring first". ;-)

I really hope you can help us. Kind regards and greetings from Berlin
Sebastian

« Last Edit: March 02, 2010, 01:06:34 am by berlin »

trentend

  • Veteran
  • ***
  • Posts: 117
    • View Profile
I haven't got time to add my detailed thoughts on this at the moment, but I will.

I would say this, seriously consider going with your preferred wiring scheme up front.  Any standard scheme later converted to a bus based switch system will increase costs and reduce effectiveness in the long terms.  One of the advantages of the KNX bus system for switches is that:

1. The bus system can be a tree structure (as long as you don't have a closed loop).  This means you can go from switch to switch, or branch to multiple switches from one feed.  I laid more than one, for flexibility and to remove single points of failure...but in principle you could just loop one wire from switch to switch.
2. The low voltage bus system means that you can put switches in bathrooms without normal mains voltage switching considerations in wet areas.
3. If you have a bus cable going to most places it's easy to add additional devices (just branch off from the nearest cable and add devices as required). 

It's much simpler (but requires more cable) to wire to each mains device (light and power socket) back to one discrete point (wiring cabinet) than having to hard wire to mains ring and via a mains switch to a light socket.  The bus system means that you can switch anything for which you have an output relay, and it's totally reprogrammable at any time.  Once hardwired it's totally inflexible.  Adding switchable devices on top of that adds an extra layer of complexity.  you would also need to add bus cable to each socket that you potentially needed to control (rather than having the relay in your wiring cabinet).

Additionally, if you use something like the Zennio Z38's as your switches (at least where you need temperature control) they have climate control features built in and become more cost efficient (they also have the option to send many switch control signals as well as scenes, potentially allowing them to replace multiple switch locations with one central touch screen control switch (thus potentially controlling multiple rooms lights, power, and heating/cooling from one place).

If the intention is to do it very cheaply, then don't consider KNX.  If the intention is to do it the best way possible then KNX may be what you want, but it's better to plan it in its optimal form from the start.

Also I can give you guidance on what I have done, but I'm in the UK and our electrical regulations are most likely different (although there are many similarities and few differences).  I'm not qualified to talk for your location, though. 

I've had training on KNX, and have all the technical documentation needed for implimenting a system.  I also have a licence for the ETS software.  What are you planning on doing for software/programming?  It's circa £1000 for a licence.

If you are serious about a KNX based system it's worth buying a small collection of devices and mocking up a test system to see how they work.  It becomes a lot clearer when you have done that.

Marie.O

  • Administrator
  • LinuxMCE God
  • *****
  • Posts: 3675
  • Wastes Life On LinuxMCE Since 2007
    • View Profile
    • My Home
One thing to note regarding dimming. Dimming sounds cool in general, and I was sold on dimming lights as well.

After doing some research, I will not put dimmers into my place, but will put a couple of more light circuits. Why? Because there is NO lighting system (other than using tubular lights) that allows energy efficient dimming that I know of. On one of the mailing lists someone suggested to use multiple light circuits to create the same effect. i.e. instead of a single light circuit with 20x 12W lights, have two circuits, and use scenarios to turn on one or both. Might be an idea.

Whether or not KNX is the right way to go, I don't know either. Z-Wave is an option for your size of flat. Another thing to think about is, where do you really need a switch, and where a simple motion sensor might be a better idea.

Another thing to rethink is, if you really want to have pre-wired scenes, i.e. why a single circuit B, and not have different circuits, which are could be grouped together or used separately.

All in all, really think about usage scenarios, and try to do some out-of-the-box thinking.

trentend

  • Veteran
  • ***
  • Posts: 117
    • View Profile
One thing to note regarding dimming. Dimming sounds cool in general, and I was sold on dimming lights as well.

After doing some research, I will not put dimmers into my place, but will put a couple of more light circuits. Why? Because there is NO lighting system (other than using tubular lights) that allows energy efficient dimming that I know of. On one of the mailing lists someone suggested to use multiple light circuits to create the same effect. i.e. instead of a single light circuit with 20x 12W lights, have two circuits, and use scenarios to turn on one or both. Might be an idea........

I'm like you.  originally wanted dimmers, but the more I looked at it, the less I thought it was a good idea. In the end I settled for each light or group of lights controlled independently with switchable sockets for lamps.  I feel this has given me the flexibility we need for lighting scenes, but kept the setting of those scenes independent of any specific type of lighting (I just switch them on or off in different combinations).  I use a mixture of ordinary light fittings with energy efficient bulbs, LED's (specifically running up the stairs which looks ace along with cupboard lighting) groups of spotlights, and lamps.

Being a photographer influences my sensibilities and I like the idea of different types and directions of lighting, more than one source with variable brightness.

berlin

  • Newbie
  • *
  • Posts: 5
    • View Profile
I knew it was a great idea to post into that forum!  ;D I'm reading everything you write with interrest. As mentioned I'm completely new to home automation (luckily not to Linux in general) so thank you for every suggestion and please keep on sending more ideas.

Sebastian

trentend

  • Veteran
  • ***
  • Posts: 117
    • View Profile
It sounds like a stupid question, but could you locate your wiring cabinet in the centre of your property - somewhere in the region of your lights "A"?

berlin

  • Newbie
  • *
  • Posts: 5
    • View Profile
There is no such thing as a "stupid question". :-)

Sorry, no way to place the wiring cabinet anywhere near the center. The problem is that the wall below the lights is only 2 meters high and is fixed only at four points to the walls on the left and right. It's meant as an eye catcher. Centering the wiring there wouldn't be a good idea.

Maybe I could place it under the stairs but that wouldn't help much, right? Maybe in the storage room in the first floor. That could bring it a little more to the center. How much space will be needed for that? [Edit: all the cables (phone, electricity, cable tv) arrive in the Room marked "HWR".]

Sebastian
« Last Edit: March 03, 2010, 09:20:45 am by berlin »

trentend

  • Veteran
  • ***
  • Posts: 117
    • View Profile
The thing about a wiring cabinet is that all wires come back there (cat6, bus cable, and in my case an individual electrical cable for each socket and light (or light group).  The more central that is, the easier it is to route cables, and the less it costs.

berlin

  • Newbie
  • *
  • Posts: 5
    • View Profile
Thank you very much for your feedback and your advice, guys. I've just ordered a KNX book to get to know more.

I'm afraid that the wiring cabinet has to be in the HWR room as planned, but I think this will do. Although I have read a little about ZWave but I somehow prefer the idea of a wired automation system. So I'll try to do my planning as good as possible and place as much bus wires as possible (walls and ceiling I think).

I agree that It would be best to start up with the favourite System instead of building a traditional wiring scene and switching to KNX later. Nevertheless we stumbled upon home automation just a short time ago so we currenty don't have the time (the house is currently already pre built at the manufacturers site) nor the money (budget already exhausted) to start a full KNX system. Plus: making use of all the other LMCE features will take some time and after that (provided we THEN have enough time and money ;-) ) we will switch to KNX. That might be a kind of interresting handyman project. That said my wifes top priority is having audio streamed everywhere and home automation in general has a lower priority. So the "Marschrichtung" is kinda set... ;-)

Thank you very much for your suggestions on dimmable spotlights. We will seriously take that into consideration.

Kind regards, greetings from Berlin and a happy weekend
Sebastian

Marie.O

  • Administrator
  • LinuxMCE God
  • *****
  • Posts: 3675
  • Wastes Life On LinuxMCE Since 2007
    • View Profile
    • My Home
Just a note re costs.

If you plan thoroughly, you will find that adding KNX early on, might not add much to the overall cost. Especially in lights of reduced costs for wiring (labor).

KingCrab

  • Regular Poster
  • **
  • Posts: 45
    • View Profile
Maybe you should have a look at LCN , too. These devices are build to put behind the switch, allow dimming and switching as you like (if I remember right) and for data connection, a forth wire beside your regular (L,N,E) wires is used.
The problem is, LCN is not supported by linuxmce right now. But maybe your could do the integration yourself or your could find someone to do it ;-)

Marie.O

  • Administrator
  • LinuxMCE God
  • *****
  • Posts: 3675
  • Wastes Life On LinuxMCE Since 2007
    • View Profile
    • My Home
LCN sucks as it is NOT open. No open drivers, no open specs. Another reason why it sucks imho is the fact that only a single company makes devices for LCN.

If one does not want to add additional wires, there are two choice:

* Control using the power line, i.e. X.10, Instabus
* Wireless, i.e. Z-Wave

Seeing as he is in the process of building atm, there should be NO problem putting an additional control wire into the walls.

berlin

  • Newbie
  • *
  • Posts: 5
    • View Profile
Time has passed and the framing of the house has been built. I would like to thank you again for your support. That helped a lot.

Because it might be interresting to other newbies having the same question, here is what we did/will do:

- the lights in the groundfloor and some lights in the upper floor are connected in a "conventional manner" to the central wiring cabinet in the room marked "HWR". These lights are switched on an off by using pushbuttons (hope that's the right word), not switches. My electrician used the green EIB/KNX wire for the buttons so that we can use these cables for KNX later on.
- We will put a EIB wire in almost every wall, just a few centimeters below the ceiling with junction-boxes at strategic points
- we have used a separate wire with 5 cores instead of three to connect the power sockets in the living room. That gives us the option to decide later which power sockets should be switchable. The sockets in the kittchen are wired in the same manner with another cable, both cables ending in the HWR.
- we will put additional EIB wires to those switches that are conventional switches in the upper floor. That gives us the option to easily replace them by knx sensors if we want to.
- Most lights in the upper floor can be equipped with KNX actors easily because we have an inserted ceiling and the actors can placed in the attic.
- CAT7 cabling in almost every room

The changes mentioned above cost about 200,-€ extra (not including the CAT7 wiring) and give us full flexibility to switch to home automation later on. We are very happy with that solution because we can extend it step by step as we develop new ideas.

Please excuse my terrible english. I had to look up almost every second word and I'm pretty unsure about the technical terms.  ???

If you are interrested (and maybe are able to read some german) - we are blogging the complete building process and I will describe our wiring strategy in german:

http://jetztwirdgebaut.blogspot.com

And please do not hesitate to click on the interresting google ads there... That helps me to buy the nessessary KNX equipment even earlyer... ;D

Greetings from Berlin
Sebastian
« Last Edit: April 24, 2010, 09:51:20 pm by berlin »

totallymaxed

  • LinuxMCE God
  • ****
  • Posts: 4660
  • Smart Home Consulting
    • View Profile
    • Dianemo - at home with technology
Thank you very much for your feedback and your advice, guys. I've just ordered a KNX book to get to know more.

I'm afraid that the wiring cabinet has to be in the HWR room as planned, but I think this will do. Although I have read a little about ZWave but I somehow prefer the idea of a wired automation system. So I'll try to do my planning as good as possible and place as much bus wires as possible (walls and ceiling I think).

I agree that It would be best to start up with the favourite System instead of building a traditional wiring scene and switching to KNX later. Nevertheless we stumbled upon home automation just a short time ago so we currenty don't have the time (the house is currently already pre built at the manufacturers site) nor the money (budget already exhausted) to start a full KNX system. Plus: making use of all the other LinuxMCE features will take some time and after that (provided we THEN have enough time and money ;-) ) we will switch to KNX. That might be a kind of interresting handyman project. That said my wifes top priority is having audio streamed everywhere and home automation in general has a lower priority. So the "Marschrichtung" is kinda set... ;-)

Thank you very much for your suggestions on dimmable spotlights. We will seriously take that into consideration.

Kind regards, greetings from Berlin and a happy weekend
Sebastian

Hi there,

Really the important thing is to locate the central equipment rack in a location with adequate space and good ventilation (either to the outside world directly or via a Heat Exchanger to 'grab back' some of the energy expended). If your building from scratch the cost difference will be very small. Always run more cable than you feel you need both for the EIB bus and also for your LAN too. We always recommend running at least 3 x CAT6 cable to each location where you might want a media device for example...this gives you the flexibility to locate hardware like MD's in-room or back inthe central rack and it also allows for unexpected cable failure (it happens quite often and one the walls are skinned and finished is not fixable to be frank). Running cable again is really cheap now compared to having not run the one cable you need after your home is complete ;-)... as i have said here and to our customers many time "the cable you don't run is the most expensive one!"

Of course with LinuxMCE you have immense flexibility to intermix different technologies to achieve what you need or to 'fix' mistakes you made earlier ie you might go with KNX but once the house is complete and you have lived in it for a while you may discover that there are light switch locations that you just did not plan for... well no problem just add a Zwave/ENocean interface to your Core and have a ZWave/ENocean radio light switch control the appropriate KNX switched/dimmed load...problem fixed :-)

All the best


Andrew
Andy Herron,
CHT Ltd

For Dianemo/LinuxMCE consulting advice;
@herron on Twitter, totallymaxed+inquiries@gmail.com via email or PM me here.

Get Dianemo-Rpi2 ARM Licenses http://forum.linuxmce.org/index.php?topic=14026.0

Get RaspSqueeze-CEC or Raspbmc-CEC for Dianemo/LinuxMCE: http://wp.me/P4KgIc-5P

Facebook: https://www.facebook.com/pages/Dianemo-Home-Automation/226019387454465

http://www.dianemo.co.uk