Patch Panel

Hi there,

I have just finished wiring up my patch panel for all the input devices for my CBUS installation. Now I am not sure if it is a good idea what I have planned but thought it would be the neatest method for terminating the individual devices from the field.

I have simply looped all patch ports together on the back and tested each port for correct wiring and all is fine. This basically allows me to terminate all remote cables into another patch panel or just terminate each cable with an RJ45 plug and plug them directly in.

Your thoughts are greatly appreciated.

 

After 75 views no one has any opinion on this setup?

I am new to this and just need some guidance on the wiring. If this is a stupid idea I would rather know about it now rather than later.

Can someone shed some light on what their prefered method of wiring up input devices to the network backbone is. This is information that is not easily found on the various sites. Not asking for "trade secretes" here just some guidance.

Thanks in advance Arthur

 

I was going to wait unit it got to 100 views before I commented

Looks good, you are probably going to alot more effort and expense than most.

Depending on the size of the job; most people would just use a terminal strip or a Krone frame to terminate the C-Bus cable. Some just use BP connectors

 

Peter,

Thanks for the reply. I initially thought about using krone termination strips but thought this would be a cleaner solution. My only concern was the noise, if any, it might introduce into the cbus backbone.

I am a bit of a neat freak with cables so I thought this would achieve the cleanest outcome.

Once again thanks for the input.

Arthur

 

This is kind of backwards

The C-bus cable is a solid strand cable and (just like every other cat5/6) is meant to be used in walls and usually terminated on the rear of these patch panels.

The flex version is then used on the front to patch between it and hubs/devices.

You will be patching in solid cable to the front now. You will need cable management solutions as well (I assume it will be rack mounted).

Otherwise, I have heard of others doing the same thing and no comments have been made on any problems experienced.

Mick

 

Mick,

Yes you are correct that the CBus cable is a solid core cable. Cat 5/6 cable is solid core if you run the LAN cable and stranded core for patch leads. My question then is, are the short patch leads that come with the devices solid or stranded core? If they are solid core then this situation is no different. Otherwise do they sell stranded core patch leads for CBus? I am more than happy to terminate the field cables to another patch panel. For the sake of $140 for a Krone patch panel to make the job neat and tidy it doesnt bother me. Also what would the implications be if you were to use LAN Patch leads to interlink the various components together?

The whole idea of it being solid core does not / should not prevent it from terminating to a RJ45 plug. The issue is how much movement will the cable experience and what is the potential of it breaking.

Regards
Arthur

 

Stranded

 

At the end of the day as long as they are all connected together in some fashion it will work.

Znelbok is correct, it is a little backward. That's why I mentioned the Krone frame.

 

Just to add to that, there are different plug for standed and solid cable, but as stated as long as they are connected.

I terminate the solid core in a surface mount network connector (punch down), but I have also made my own patch leads from solid core (as would have many installers) and they work fine.

Mick

 

Mick,

Yes I should have pointed out that my background is IT / Datacomms and have done a fair amount of work with Cat 5/6 cabling and know of the different types of RJ45 available.

Is it possible to buy stranded core CBus cable in a box? As a matter of interested rather than a desire to do so.

Regards
Arthur

 

The Clipsal Pink Cat5 is solid core.

 

Interesting that you are using a Krone patch panel not a Clipsal one .
In my experience a Clipsal one is cheaper anyway.

 

Missing the point!

Sorry to sound ignorant but I am not sure if i see any benefit in wiring your installation this way. I thought part of the 'flexibility' of c-bus was that it was based on a star topology. I.E: if you ran a c-bus cable through most of the walls of you home at say mm and a cable in the roof space, and if you wanted to install an additional switch, you could just cut a hole in the wall, find the cable, cut, join and terminate it in the switch (or whatever I/O you desire), program the unit and you're done! Then if you wanted to add another switch near by, again wire a new cable from the new hardware to any other c-bus termination point and join it up (provided there is not more than 3 or 4 in one termination).

I do see some merit in having a few c-bus RJ45 jacks around for connection of say desk mounted B&W touch screens, MARPA, etc, but not much else. I just see it as excessive cost for little or no gain.

 

You have some valid points ICS-GS, but ArthurK seems to have been more interested in keeping things neat. He is also from an IT background, and his method of wiring is along the same lines of an ethernet network topology. There is nothing wrong with his method, in fact it gives some decent advantages. It allows much easier fault-finding, isolation of certain network segments if required, as well as minimising the number of POSSIBLE faulty connections in the system, and I'm sure there are many more advantages that I havent said here.

I dont think Arthur was meaning that he was going to put RJ45 sockets all through the roof/house/etc, and plug all his devices into them, I think he meant he was going to have several runs of pink C-Bus cable running outwards from a central point, in a large-scale star topology, and hard-wire each device straight into the cable.

It might seem like a waste of money, but cable is pretty damn cheap really, and his Krone patch-panel is peanuts in the scheme of things, compared to the cost of the actual C-Bus equipment.

But really, everyone is entitled to their own opinions, and C-Bus is an incredibly flexible system, especially when it comes to wiring topology. So realistically, everyone is right, lol

 

Nobody else seems to have said it, so I will...

There is no need for patch panels, which is the reason you cannot find any information on them !

The C-Bus system is deliberately designed NOT to be wired like a LAN, where all the remote units coming back as individual cables to a central point.

You achieve no advantages in neatness, reliability or anything else by doing it that way. You lose flexibility and it does NOT make troubleshooting easier either ! All you are doing is adding cost and complexity - In actual fact, wiring it like a LAN might arguably make the system slower, as it considerably increased to amount of cable and the propogation distances in the system !

The "normal" method is to run ONE cable between each unit, looping in and out, and branching off as required - so called "Daisy-Chain" topology. It is reasonable to have a couple of separate runs of cables to input devices - say one for each floor, but definitely not useful to have a separate run out to each input (or output) device.

Have a read of this installation training document :

http://www2.clipsal.com/cis/__data/page/1930/C-Bus_Hardware_Installation.pdf

Hope that makes sense, John

 

The length of a C-Bus network can have no impact on the network speed unless it does so through a secondary mechanism (improper network impedance, excessive voltage drops etc that make the network unreliable). The propagation delay through 1000m of CAT5 cable is about 5.55 microseconds which is much smaller than the duration of a single bit period.

 

Sorry JohnC,

I think I have not explained what I meant as well as I thought I had.

I wasn't talking about running a seperate cable to EACH device on the network, just one cable per room, per floor, or per area of a large house. I guess the idea I had in my head was of running a single run to each enclosure that contains C-Bus output units, like your suggestion a while ago about splitting the C-Bus devices up and not putting them all in a central point. And then running all the input devices off that same leg of the star.

Anyway, I'm sorry if I have offended you in any way mate

 

Thanks for the info everyone.......

JohnC, it is interesting you call daisy chaining normal method. I would have thought that the "star" topology would be the better option especially when it comes to power distribution to the CBus network. With the star topology the power resides virtually in the centre of the network whereas in a daisy chain it needs to sit either at the ends or at any other predetermined location.

With my limited knowledge of electronics I would have thought that power loss in the cable would be greater in a daisy chain network and potenially more issues could arrise from faulty "middle" devices. At least in a star topology the end device will not take out any other device.

At the same time I dont see why you wouldnt take advantage of both methods. To me the star topology makes sense, especially in a "standard" residential setup. In a large network I can see how daisy chaining makes sense, especially with the limitation of 1000m of cable per network.

The house we are about to build is approximately 1000sqm over 3 stories. With the CBus hardware placed in the centre of the construction (or close to it). This makes the furthest input device approximately 13metres away from the termination point. At approximately 28-35 input devices we will be less than 450 metres of cable. In a daisy chain solution that would probably reduce by half. We are talking about a box of cable that costs $120 trade and a patch panel at $140 trade. On an install that will cost approximately $12000 in hardware its a small price to pay.

At the end of the day the star topology appeals for its simplicity and the minimum requirement of twisting two cables together - which I see as the weakest link in a daisy chained implementation.

Similarly I am the least person to comment on best cable installation methods, especially after seeing some of the jobs you guys have been involved with. My ideas might be flawed so that is why I posed the question to the forum.

Hopefully my post is not coming across confrentational but rather openly discussing a topic.

Regards
Arthur

ps the whole network would have a maximum diameter of 24-26 meters therefore propogation should be conciderably faster in this setup. Unlike a daisy chain the maximum distance to any device is the distance between the two furthest connected star devices. In my situation 26-28 metres.

 

Yes it will, the patch panel offers you no isolation between legs.

It won't make any difference, the messages are broadcast and received by all units at once, they are not retransmitted through each unit. C-Bus data speed is slow (compared to ethernet) and for good reason, it makes it very tolerant to the type of cable used and how it is wired.

Wire it how you like.... because with C-Bus you can. It's low speed, multi drop and tolerates a wide supply voltage.

In short, it's designed that way.

Forget everything you know about ethernet and comparing it to C-Bus, they have nothing in common, not even the cable. The first series of C-Bus stuff that I had was wired up using 2 pair phone cable.

Cheers

Rohan