Maybe someone here has a good idea:
For cost reasons, I planned all the push buttons (light switches, blinds, etc.) in our KNX house using a conventional switch system (so no "smart" push button terminals or high-end ones). To be future-proof (possibly for some network/internet-based control unit eventually), I installed CAT7 cables everywhere—so no 230V wiring.
So far so good... With this approach, I gradually wired the entire house. Now, in the technical room downstairs, I have about 70 CAT7 cables converging, of which I usually only need two conductors each. I don’t yet have a clever idea how to neatly terminate them. In my test setup, I just connected everything with a few Wago connectors.
In the distribution panel, all 230V wiring goes onto Wago TopJob connectors, which works perfectly for internal connections. But I don’t want to put all 70 CAT7 cables into there. That would be too chaotic. Also, I haven’t found anything suitable from Wago for this purpose.
So I need a smart terminal or wiring solution that can reduce the number of cables or conductors, making it manageable to feed into the distribution board.
I know this is very specific. Until now, I haven’t heard of anyone wiring like this. But maybe you have an idea of something suitable—perhaps from a different context.
For cost reasons, I planned all the push buttons (light switches, blinds, etc.) in our KNX house using a conventional switch system (so no "smart" push button terminals or high-end ones). To be future-proof (possibly for some network/internet-based control unit eventually), I installed CAT7 cables everywhere—so no 230V wiring.
So far so good... With this approach, I gradually wired the entire house. Now, in the technical room downstairs, I have about 70 CAT7 cables converging, of which I usually only need two conductors each. I don’t yet have a clever idea how to neatly terminate them. In my test setup, I just connected everything with a few Wago connectors.
In the distribution panel, all 230V wiring goes onto Wago TopJob connectors, which works perfectly for internal connections. But I don’t want to put all 70 CAT7 cables into there. That would be too chaotic. Also, I haven’t found anything suitable from Wago for this purpose.
So I need a smart terminal or wiring solution that can reduce the number of cables or conductors, making it manageable to feed into the distribution board.
I know this is very specific. Until now, I haven’t heard of anyone wiring like this. But maybe you have an idea of something suitable—perhaps from a different context.
C
cybergnom30 Jan 2019 19:50Do I understand this correctly... You planned to use standard switches for cost reasons and now have 70 (???) switching points in the house? So one switch for each lighting circuit, one for each blind group, and so on? And each connected separately in a star topology to the distribution board?
How does that add up? Compared to 2-3 KNX lines with an estimated 15 “smart” push-buttons?
And how do you connect the push-buttons to the bus? Are you using the CAT7 cable as the bus line?
How does that add up? Compared to 2-3 KNX lines with an estimated 15 “smart” push-buttons?
And how do you connect the push-buttons to the bus? Are you using the CAT7 cable as the bus line?
I never said that was a smart move 🙂
And OK, the 70 was just an estimate. I didn’t count them – it just felt like at least that many. I just counted again: there are actually only 48. But yes, as you say, one wire for each function. And all star-wired to the basement. In the worst case, I can combine the 4x2x0.25 mm² (4x2x0.0004 in²) into 4x0.5 mm² (4x0.0008 in²) or 2x1.0 mm² (2x0.0016 in²) and put the KNX bus on top, that’s the basic idea – but not the main goal.
In the living room, I’ve already installed KNX cables to work with KNX control units and scenes. But for example, for the bedside light and other “simpler” functions, I wanted to keep it straightforward. Also, my wife just wants it like before. So simple push-buttons are needed. Of course, there will also be presence and motion sensors, but only when there is money left over. That’s why I’m doing all the KNX stuff myself. And that’s why for now just ETS light and fewer than 20 devices. If I wanted KNX push-buttons everywhere, that wouldn’t be feasible.
The standard push-button (total cost 10 euros) connects to the bus via a binary input (I’m considering the 16-channel ones from MDT at about 15 euros per channel). That brings the cost to around 25 euros per push-button, which is definitely cheaper.
From 4 functions upwards, an intelligent KNX control unit pays off. Although I haven’t found anything nice that matches our Jung LS990 switches – but that’s not the topic right now.
And now I have the dilemma of how to bring the relevant wires neatly into the distribution board.
And OK, the 70 was just an estimate. I didn’t count them – it just felt like at least that many. I just counted again: there are actually only 48. But yes, as you say, one wire for each function. And all star-wired to the basement. In the worst case, I can combine the 4x2x0.25 mm² (4x2x0.0004 in²) into 4x0.5 mm² (4x0.0008 in²) or 2x1.0 mm² (2x0.0016 in²) and put the KNX bus on top, that’s the basic idea – but not the main goal.
In the living room, I’ve already installed KNX cables to work with KNX control units and scenes. But for example, for the bedside light and other “simpler” functions, I wanted to keep it straightforward. Also, my wife just wants it like before. So simple push-buttons are needed. Of course, there will also be presence and motion sensors, but only when there is money left over. That’s why I’m doing all the KNX stuff myself. And that’s why for now just ETS light and fewer than 20 devices. If I wanted KNX push-buttons everywhere, that wouldn’t be feasible.
The standard push-button (total cost 10 euros) connects to the bus via a binary input (I’m considering the 16-channel ones from MDT at about 15 euros per channel). That brings the cost to around 25 euros per push-button, which is definitely cheaper.
From 4 functions upwards, an intelligent KNX control unit pays off. Although I haven’t found anything nice that matches our Jung LS990 switches – but that’s not the topic right now.
And now I have the dilemma of how to bring the relevant wires neatly into the distribution board.
C
cybergnom30 Jan 2019 22:24The calculation doesn’t add up 😉
For 47 “simple” switches, depending on the setup, you’d need about eight 6-gang or twelve 4-gang push buttons. That comes to roughly €500 or €650 versus €1,175.
The ETS issue could have been solved with multiple projects.
I can’t argue against the WAF (Wife Acceptance Factor) argument 😉
Although I can imagine that having two control concepts might get annoying for your wife in the long run...
But anyway, it doesn’t matter now since the house is already built.
I’m not an expert, but somehow you have to connect the wires to the binary inputs.
So, either you put all the CAT cables onto terminal blocks in the distribution panel and then pass on the relevant wires. Or you do it decentrally, create some kind of CAT sub-distribution somewhere, and only run the KNX cable to the main distribution. It really depends on the local conditions...
For 47 “simple” switches, depending on the setup, you’d need about eight 6-gang or twelve 4-gang push buttons. That comes to roughly €500 or €650 versus €1,175.
The ETS issue could have been solved with multiple projects.
I can’t argue against the WAF (Wife Acceptance Factor) argument 😉
Although I can imagine that having two control concepts might get annoying for your wife in the long run...
But anyway, it doesn’t matter now since the house is already built.
I’m not an expert, but somehow you have to connect the wires to the binary inputs.
So, either you put all the CAT cables onto terminal blocks in the distribution panel and then pass on the relevant wires. Or you do it decentrally, create some kind of CAT sub-distribution somewhere, and only run the KNX cable to the main distribution. It really depends on the local conditions...
cybergnom schrieb:
I’m not an expert, but somehow you have to connect the wires to the binary inputs. Haha, me neither. And that’s exactly what the “somehow” is about here ;-)cybergnom schrieb:
So either you put all the CAT cables in the distribution panel onto terminal blocks and then continue the relevant wires from there.That’s already where the problem starts, because I don’t know of any suitable terminal blocks. Also, all the cables won’t fit in there anyway. So it will have to be an external solution to reduce the number of cables (or better, the total cross-section). But yes, I’m specifically looking for an elegant way to “pick out” the relevant wires.cybergnom schrieb:
Or you do it decentrally, installing some kind of CAT sub-distribution somewhere and then only run the KNX cable to the main panel. It really depends on the local conditions.There is space next to the panel. A server (wall) cabinet will be installed there sooner or later. In or above or below that cabinet, the cables could be routed and connected to something (?) or clamped (?). Basically some kind of patch panel for CAT cables, as commonly used.