Author Topic: Linux MCE beating as the heart of whole house automation  (Read 50128 times)

mcefan

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Re: Linux MCE beating as the heart of whole house automation
« Reply #15 on: September 18, 2012, 06:05:06 pm »
I don't know how it is that I can't find these things, but thank you!

http://wiki.linuxmce.org/index.php/EIB/KNX_Devices

I did some reading, made some calls, waiting for return calls from element controls and others ...

mcefan

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Re: Linux MCE beating as the heart of whole house automation
« Reply #16 on: September 18, 2012, 06:22:09 pm »
Echoing what several have said, enjoy the flexibility to wire the place 'til it looks like charlette's web.  And run extra. 
Great suggestions! I will apply them all.

I have a couple of questions:
What do you mean by extra? Length, or extra runs?

  • New LED lighting is coming out that will allow lights to run using a standard POE switch and be controlled by it.  I would venture to run some cat5/6 to the light fixtures or at least nearby.
  • Run a neutral everywhere, many controllers need the ability to power themselves without trickling power through the device.  This includes at the light switches.  Instead of running the power to the fixture and then a switch leg to the switch, run the power to the switch and then up to the fixture. 
Would you have links to these lights?
During wiring, I labeled both ends, and homeruned to the switches. I kept the low voltage 16in away because of potential power surges. How should the cat wiring for lighting be done while keeping away from the fixture? I would like to reuse the same locations. I'm thinking of coming from the opposite direction with the cat, ending at the fixture, without terminating both ends. I can always disconnect the romex when needed, but how would you do it?

hari

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Re: Linux MCE beating as the heart of whole house automation
« Reply #17 on: September 18, 2012, 07:05:01 pm »
and if you're smart you're running your cabling for switches, lamps and appliances in a star originating from your closet. That way you can devices with multiple channels (cheaper) and easily replace them if some other system evolves over the next decades.
rock your home - http://www.agocontrol.com home automation

mcefan

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Re: Linux MCE beating as the heart of whole house automation
« Reply #18 on: September 18, 2012, 08:02:38 pm »
and if you're smart you're running your cabling for switches, lamps and appliances in a star originating from your closet. That way you can devices with multiple channels (cheaper) and easily replace them if some other system evolves over the next decades.
actually, everything  homeruns to the breaker box now. I was actually thinking of doing exactly that, but I don't know how the HA equipment works, so I was not sure it was the right thing to do. I will reroute the electric then.

To make sure I get it right:
  • run homeruns to a ???? in the wiring closet
  • wire all switches from the ??? location
  • do the same with cat6

is that right?
All the KNX stuff I've seen so far here seems to not need the LMCE. It is advertised as "no computer needed", and pricey. What should I be looking for?
« Last Edit: September 18, 2012, 08:05:48 pm by mcefan »

tschak909

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Re: Linux MCE beating as the heart of whole house automation
« Reply #19 on: September 19, 2012, 03:29:56 am »
You are quite right, KNX is very autonomous. All home automation busses typically are, be they KNX, Z-Wave, X-10, PLCBUS, whatever.

This is for a lot of reasons, but really, all that is relevant here is that LinuxMCE merely acts as a sort of submissive slave. It will politely ask, through its computer interface to the bus to do certain things, "Turn on the bedroom light", "Set the air conditioner to 70 degrees F", and assuming things are kosher, the devices on the other end of the bus will comply, and do them. Similarly, if an event comes across the wire, say the thermostat says, "The room temperature is now 70 degrees." LinuxMCE can take this event and react to it somehow, however you wish.

KNX can take this to an extreme degree, and it's a good thing. It means, that if the computer goes boom, the sensors (in this case, the switch on the wall) you've mapped to the actors controlling the light, will still function.

All that LinuxMCE cares about, is its interface to the bus, and that it knows what is on the bus, so it can know where things are, what commands can be sent, and if an event comes across the wire, where it came from.

So yes, you don't NEED the computer, but the computer opens up additional possibilities, and as long as there is an interface to the bus, and LinuxMCE knows how to talk to it, LinuxMCE can be used to either send commands to it, or listen to events from it.

It also opens up the possibility to mix and match. If you have, say, Z-Wave, and KNX devices, you could attach computer interfaces to the LinuxMCE core (or media directors, it really doesn't matter, especially if the media directors stay on), and then issue commands from LinuxMCE and LinuxMCE will do the right thing. It makes LinuxMCE a sort of United Nations in the middle, and ultimately allows you to have a wider selection of choice.

-Thom

mcefan

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Re: Linux MCE beating as the heart of whole house automation
« Reply #20 on: September 19, 2012, 06:06:24 am »
All that LinuxMCE cares about, is its interface to the bus, and that it knows what is on the bus, so it can know where things are, what commands can be sent, and if an event comes across the wire, where it came from.

So yes, you don't NEED the computer, but the computer opens up additional possibilities, and as long as there is an interface to the bus, and LinuxMCE knows how to talk to it, LinuxMCE can be used to either send commands to it, or listen to events from it.

It also opens up the possibility to mix and match. If you have, say, Z-Wave, and KNX devices, you could attach computer interfaces to the LinuxMCE core (or media directors, it really doesn't matter, especially if the media directors stay on), and then issue commands from LinuxMCE and LinuxMCE will do the right thing. It makes LinuxMCE a sort of United Nations in the middle, and ultimately allows you to have a wider selection of choice.

-Thom

Thank you for making it plain for me Thom. Despite the reading, it was still a bit elusive (I think it's because the documentation focuses mainly on the technical aspects of things). You've made it clear: the LMCE core is essentially a command and control center for various HA technologies, each with their own merits and problems.
So, now I need to wisely choose devices.

Just out of curiosity, if the wire is used for signaling, how do the different protocols avoid conflicts?


tschak909

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Re: Linux MCE beating as the heart of whole house automation
« Reply #21 on: September 19, 2012, 06:15:14 am »
Different busses each require their own wiring and signalling requirements. None of the busses can share the same physical topology, as they are each proprietary.

* X-10, PLCBUS, and INSTEON work over the existing power lines, Insteon does have a wireless bridge to overcome phase coupling problems, and some X-10 devices do transmit wirelessly (i.e. sensors)
* Z-Wave and ZigBee, work over wireless transmission
* KNX works over its own dedicated twisted pair signaling cable, although KNX does have options to work over power line, and over wireless (RF)

-Thom

mcefan

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Re: Linux MCE beating as the heart of whole house automation
« Reply #22 on: September 19, 2012, 03:03:49 pm »
    Different busses each require their own wiring and signalling requirements. None of the busses can share the same physical topology, as they are each proprietary.
    (... for obvious reasons: they'll talk over each other and no device will understand anything since no communication sent remains unchanged.
    ... and there is no arbitration...)

    Whaoo!
    Boy, this thread is quickly becoming a stickie for noobs (like me). I don't know if it's me, but I did not have as clear an understanding from my previous readings. This kind of stuff should be placed on top of the wiki. I will even volunteer to write, if someone will work with me.

    That said, now I understand why I was asked to pull cat wire: with KNX, it's used for signalling, and it needs to reach wherever there is something to control. Which brings me to another conclusion: I need to use different color wires to distinguish the control bus to from the LAN that I am pulling.

    Now my concern is crosstalk and power surges:
    if a cat bus wire is pulled along side or parallel to the electric wires,
    • communication will not be clean (there will be errors in transmission caused by electric surges)
    • there is a high probability that a power surge will damage the equipment on the bus.

    To avoid those problems, I need to keep the cat wires at least 16in away.
    Good thing I'm replacing the breaker panel also! I'll purchase one with whole house surge protection, and I think there are breakers that come now with surge protection also, I'll use that on the KNX bus (if I can afford to go that route).

    So, that's where my understanding gets me so far...

    Which leads me to:
    • Where does the cat wires terminate (KNX)?
    • How is the setup for the lights over cat supposed to be done?
    [/list]
    « Last Edit: October 01, 2012, 08:10:24 pm by mcefan »

    Marie.O

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    Re: Linux MCE beating as the heart of whole house automation
    « Reply #23 on: September 19, 2012, 03:27:09 pm »
    I run my KNX wires directly alongside my 230V power cables, my CAT6 and CAT7 cabling, 3x 30m speaker wire, and the low voltage stuff from my 30kWh peak PV installation, without any problems.

    mcefan

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    Re: Linux MCE beating as the heart of whole house automation
    « Reply #24 on: September 19, 2012, 04:07:32 pm »
    I run my KNX wires directly alongside my 230V power cables, my CAT6 and CAT7 cabling, 3x 30m speaker wire, and the low voltage stuff from my 30kWh peak PV installation, without any problems.
    That won't meet code over here. The inspectors would fail that setup. They actually come and look at each wire, gages, routing and all...
    It has to be kept 16in away.

    What's "30kWh peak PV" used for?
    Once you pull your bundle as you said, do you just continue to pull to the individual locations, or is there any kind of junction boxes used in the process.
    Where do the cat wires terminate (switch/lights/plugs/junction...)?

    jacac

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    Re: Linux MCE beating as the heart of whole house automation
    « Reply #25 on: September 20, 2012, 07:54:33 pm »
    I did some reading, made some calls, waiting for return calls from element controls and others ...

    Hey,

    let me know if you get a reply form element controls. I've contacted them twice and never heard back.

    -jacac

    Marie.O

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    Re: Linux MCE beating as the heart of whole house automation
    « Reply #26 on: September 20, 2012, 07:59:04 pm »
    The KNX cable is specified to be put together with high voltage (230V) cabling.

    We have a photo voltaic installation that has 30kWp. Around 50% of the power generated is used by us, the rest is send into the grid.

    KNX cable can be intersected however you like. i.e. you can build a tree, or a single line, doesn't matter. I have a tree with lots of branches. As long as you do not produce a loop, everything is allowed.

    In our situation we have multiple switches for the CAT cabling. Otherwise the cable runs would have been too long. I have a backbone which connects 5 switches throughout the home, plus a couple of local access points/switches in the office(s)

    mcefan

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    Re: Linux MCE beating as the heart of whole house automation
    « Reply #27 on: September 21, 2012, 04:24:49 am »
    Hey,

    let me know if you get a reply form element controls. I've contacted them twice and never heard back.

    -jacac

    I finally just spoke to the engineer @ element controls: very nice guys. I just kept calling every couple of hours until I finally got him. He immediately listened to my plans, asked me to send him some drawings by email, which I did, and we discussed the whole thing for over 30 mins. Outstanding service. He is going to give the drawing to the lighting guy tomorrow to size the loads, then they will call me and we'll work out the switches and all, so I can have a quote. Definitely more than anything I expected.
    I don't know what the rules are on this forum for contacts, but I have his email. He says that he is easier to get via email because of all the meetings he has to attend. Apparently, they do a lot of on site customizations and installations and work with all the people involve in the building industry, especially on large project like hospitals and the like, where automation has to be serious, advanced and reliable.
    I just hope the products are affordable for some home owners projects.

    I'll keep you posted

    mcefan

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    Re: Linux MCE beating as the heart of whole house automation
    « Reply #28 on: September 21, 2012, 04:35:30 am »
    KNX cable can be intersected however you like. i.e. you can build a tree, or a single line, doesn't matter. I have a tree with lots of branches. As long as you do not produce a loop, everything is allowed.

    Are you referring to the TP used for signaling? I thought the power had to be homeruned to a central location?
    I'll ask the engineer @ element controls what their requirements are tomorrow. They were already closed when I called (he still picked up my call an worked with me for an hour).

    Please take a look @ the elements in the "smart box" and tell me what you think:  http://www.elementcontrols.com/smartbox/

    mcefan

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    Re: Linux MCE beating as the heart of whole house automation
    « Reply #29 on: September 21, 2012, 04:47:29 am »
    - lighting control

    I'd recommend a cabled system like KNX over wireless solutions like Z-Wave

    Can you elaborate on why?