Some KNX questions...

[McKajVah]

I'm building a house and want to use a KNX installation in my house. I want to buy some "basic" components, so that I can program, learn and test before I go out and buy 20.000,- EUR of equipment. I therfore have some questions I hope someone can answer.

Like I said in a post before, I often travel leaving the house with my wife and kid alone for 2-3 weeks. And therefore want to have it as stable/reliable as possible.

1.
I plan to later buy a Gira Homeserver and intergate it with other IP/Ethernet equipment and I also want to program with ETS via IP.

- What is the best way to connect the Homeserver to IP and EIB bus?
- I've read somewhere that the EIB IP Routers only can open one "tunnel" at a time, what does this mean?
- What is the most reliable way to connect the homeserver to the EIB bus? If I use the ethernet, and if the ethernet goes down, I will loose connection between the Homeserver and the EIB bus. Is this a "real/normal" problem?

2.
How are the EIBMarkt products? Thinking of powersupply with choke, ip-router/-interface and actuators.


-Kaj

[Warichet]

I plan to later buy a Gira Homeserver and intergate it with other IP/Ethernet equipment and I also want to program with ETS via IP.

If you want the remote control, the HomeServer is the best bet for you. Also, if the remote control is part of the initial project then the HomeServer should be part of your lab test.
ETS can be setup in such a way that it uses the HomeServer for accessing the bus while programming devices (that's what I'm doing anyway)

- What is the best way to connect the Homeserver to IP and EIB bus?

Personally, I've a Homeserver 2 Net (no more available) the device acts as a gateway, having one connection, via it's build in RJ45, to the LAN/IP and another connection to the KNX bus via it's build in RS232 port and an external FT 1.2 interface.
I guess there is some change in the HomeServer 3 connections, but basically, that's it.

- I've read somewhere that the EIB IP Routers only can open one "tunnel" at a time

No, not so.
By definition, a router can have many simultaneous connections.
I think you mean ....
" I've read somewhere that the EIB IP interfaces can open one "tunnel" at a time "
.... this is correct.
Check the posts about the Siemens N146 rtr and N148 I/F

- What is the most reliable way to connect the homeserver to the EIB bus?

Most of us use a LAN

If I use the ethernet, and if the ethernet goes down, I will loose connection between the Homeserver and the EIB bus.

Yes, that's for sure, but heck, your LAN config should be carefully setup. Although it's not a HomeServer topic, I would recommend good quality devices for the infrastructure, especially the LAN router and make sure you can always open a session to your rtr when you are abroad.

How are the EIBMarkt products? Thinking of powersupply with choke, ip-router/-interface and actuators.

You seem to be concerned with robustness and reliability, why not look for the best devices ?
I'm not saying that EIBMarkt products are not good or suffer any illness, I'm saying, in your situation, I wouldn't take the risk.

If you send me your email, I can give you limited access to my HomeServer, so you can make your own opinion.

[Wasserkocher]

Hey Kaj,

I hope most of your questions were already answered by the previous post. Additionally I'd like to add a few points:

You mentioned the unique tunnel problem. The IP Interface and the IP Router differ in their multicasting ability. The Router has multicasting capabilities and can therefore handly multiple connections. However, there are certain applications that require a dedicated connection to the KNX interface. Many visualization programs or the ETS for example do so. They won't connect unless they are the only dedicated request. The homeserver or many control devices like SAIA don't do that. They connect regardless of other connections, including dedicated ones.

If you connect your HS via a serial connection (only FT 1.2 protocoll) you have a sure thing. However, if your lan fails there is no way to access the homeserver comfortably anyways, so I don't think this is such a big problem afterall. I'd make sure to have a cheap backup switch ready :-) Some people prefer to have a conventional interface (RS232, USB) ready if something doesn't work, for me the IP router, no matter the brand, is the number one choice. It is just too awesome to connect the IP (with Wifi and Internet and all that) to the KNX world to miss out on that.

Are you planning to do everything yourself or will you have help? It's a large playground and there is lots to consider when it comes to planning a whole installation for a house.

Where in Norway are you from? If you live close to Oslo, the entire BI campus is KNX driven! It's worth checking out ;-)

Best
Fabian

[McKajVah]

Hi again, and thank you for your answers.

I live on the south coast of Norway 3-4h from Oslo. I'm an electrician, has done a lot of house installations (not KNX). Currently I'm working in the north sea with Fire/gas systems and large control-systems (ABB Advant OCS).

I will be doing all the installation myself, and see this as an hobby and opertunity to learn about the KNX system.

I made a quick diagram of how I currently have planned to install it, everything is not of course in the diagram, but I think you'll get the idea.

Please comment on the diagram, and if you would have done something different.

-Kaj

[makki]

Now, that looks basically fine, some annotations:

I'd put the doorcom on IP/SIP in first place, it's usually cheaper even with a high-res IP-Cam saving events on the NAS as a free side-effect and more future-proof to be used with any common phone in the house without expensive converters etc. as long as theres one gateway from SIP to PSTN. More on request, I already wrote some about that here..

The "problem" that one IP-Router can only supply one tunneling connection at a time won't hit you to hard here; the HS communicates through KNXnet/IP Routing in this case and you're left with using the one tunneling-connection for i.e. the ETS or alternatively you can use use the iETS-server in the HS to program/monitor the bus.. So basically one could think the IP-Router is obsolete and in case ther're no other devices to be connected to the bus through Routing you're as well off fine with a FT1.2 connected to the HS..

Makki

[Wasserkocher]

looks as if you have given it a lot of thought already. The schematics are alright to serve for a basic understanding on where devices are connected and what world (ethernet, knx, dali etc.) they belong to.

Dali is a good choice and adds lots of comfort and functionality at good cost/benefit.

As next step I would sit down and create a list of all the functions I want to have in my different places e.g. kids bedroom: HVAC control, blinds, three independent cealing downlights, etc. Once you know the functionality you need you can actually create a list of requirements and what devices you will need. Also the dimensions of your bus system etc. depent on that. Next plan the wires, all parallel or serial wiring, remember you will need LOTS of room for serial wiring and plan large enough recesses etc.

Fabian

[Warichet]

Also....
part of your preparation work, you could work on the design of your GA architecture.
Starting with a decision about 2 vs 3 level (I suggest 3 levels).
Your drawing might be a good place to start, defining GA by type of usage.

There are many posts about this topic. Imho, there is no good or bad, there is the one you feel most comfortable with. I've pushed the concept a bit further, by working on spreadsheets for the architecture design and for the GA assignments. So, whenever I've to add/modify a GA, I do it first on the spreadsheet to make sure it is consistent with my own rules, before implementing it in ETS.
The positive side effect is that I've an up-to-date documentation about the project (having an overview in ETS isn't always easy.

[McKajVah]

I've done some reading in the forums, but the google translator is not the best and I can't read any german......

From what I can understand most people here use KNX for roomswitches, homserver and actuators, but other systems for other functions.

- What systems do you think I should consider/leran more about in my house? I know of EIB, Dail and 1-wire.

- To me it seems that most of the different "manufacturers" for EIB components are made in 2-3 different factories, but with different company logo and plastic housing. Are any manufacturers considered as the best in regards to price/performance?

-Kaj

[Wasserkocher]

The beauty of KNX/EIB is that it is so versatile. Unlike many other systems you can almost hook up anything to the KNX. There is a great variaty of products and services that are offered from very different sources (private like Makki's 1-wire solutions, or Nils xxAPI from this forum as well as commercial like Gira, Siemens, abb etc.). KNX provides the foundation. It is not too strong with anything in particlar, but it works. For special purposes e.g. lighting -> DALI, multirooming -> Revox, Russound and what have you, there are products that fill these niches.

When you look at the different manufactureres their products are very similar. In my opinion the most important difference is the design for the roomswitches. They have to appeal to you and you have to like them. The actuator (REG) side is somewhat unimportant. Again another nice-to-have is that you can use different manufacturers and mix their devices. It will still work perfectly having a Gira actuator and an ABB dimmer right next to each other.

Then there are certain landmarks like the Homeserver. To my knowledge it is unique in its setup and place in the knx world. There are some solutions that compete with the HS like the software by Jung or other embedded solutions, but the comparison in functionality and implementation is nothing as close as for the regular devices that can only be differentiated to the margin.

If you set up your installation properly you can always extend your current bus installation with other systems and connect them to the existing installation. I think KNX and maybe DALI for lighting is a very good foundation to start with. Once you live in a place and experience new needs, you will find the niches where KNX underperforms or provides no solution at all and another system might be more adequate to augment certain capabilities. Most importantly PREPARE FOR EVERYTHING :-) In the end it is always better to have too many cables than too little...