Cbus network wiring

Hi,

Got a really simple question but am finding it very hard to find the answer.

I have a current cbus network as per the below basic diagram, I only have two cbus network ports on the 5500PC, one already used for the HMI (touch screen panel) and I/O (input/output modules) but have two new networks of devices to connect up with only one port left free on PC module.



How do I integrate these two new networks into the current cbus network?

I have called cbus tech support and browsed a lot of documents trying to find the answer, is there an port switch module or a T piece module or something?

Looking in the network quick guide on page 13, you can see a pink network cable T piecing with another but it does not say how.

Can anyone help me out please? It may seem a simple problem but without experience wiring cbus networks I am finding it frustrating trying to find an answer to this simple problem (I mean the cbus network is described as "open topology" meaning you can use any topology you want but it doesnt tell you how!!)

Thanks,

Craig

 

Craig, I would suggest spending a bit of time reading the literature available on the CIS technical website (http://www.clipsal.com/cis).

Specifically some of the training and installation documentation (http://www2.clipsal.com/cis/technic...ing2/cbus_control_and_management_system/basic) and (http://www2.clipsal.com/cis/technic...structions/cbus_control_and_management_system)

And more spefically pages 20 and 21 of the hardware installation handbook (http://www2.clipsal.com/cis/__data/page/1930/Handbook_-_C-Bus_Hardware_Installation2.pdf)

Edit:
I'm making the assumption here that when you are referring to Network #1 and Network #2, that you actually mean just two physically seperate loops of wire on the same CBus logical network. If you are indeed referring to two independant CBus networks, then you'll need a network bridge between them.

 

Thanks Froop,

I would read all that if I had time, I'm at work and simply trying to quickly find an answer for the project manager installing the new devices.

They are indeed two separate loops of cat5 cable, the physical location of the field devices made it impossible to daisy chain them all in a simple single bus network so there are two separate sections that I need to connect to the main cbus system. I have looked for a switch/hub type module or a T piece like module...surely there must be a simple solution out there, a part made specifically for this?

Thanks,

Craig

Edit: In relation to the hardware manual, I believe what I was after is on page 10....I suppose that is the simplest way if you can simply "splice" the signals as such together. Thanks for your help Froop

 

If you refer to page 19 and 20 of that last link, it shows you diagrams and pictures of how to join two lengths of CBus cable.

On a related note, I can understand a home user asking the question (I would be hypocritical otherwise!), but surely in a commercial environment the person messing with your CBus equipment should surely be CBus trained and certified??

 

cbm Craig

You are making many statements that indicate you don't really have the first idea what you are doing - I mean this in a nice way.

Froop has provided links to much of the info you need. If you don't have the time to read it then you are not going to have much fun, or success.

If your C-Bus Networks (1 & 2) don't add up to more than about 90 units or 1000 meters of cable then you can simply connect the two ends together. There is no need to be connected to a PCI for things to work - there is no central part of the system.

If you wish to have two physically separate networks then you will need a network bridge, and Toolkit programming to match.

In any case, whether 1 network or 2 networks, each network needs 1-3 devices with a network clock enabled, 1 only burden, and enough C-Bus network power to run the devices connected.

If you don't have enough time to get basic wiring right chances are you won't get much of the other important stuff right either.

Good Luck...

 

Hi Guys,

I probably just didn't explain it very well...I don't need to know how to wire the RJ45 connectors or how to join two wires together....I have two separate CAT5 cables with eight wires each. I have a central CBus system with a HMI plugged in via one of the cbus ports on an output relay which daisy chains back through another output relay, two input modules back to one cbus com port on the 5500PC module...there is one com port left but I have two CAT5 cables from two sets of daisy chained field devices (who's physical location prevented them being on one single bus length otherwise I wouldn't need to do this) to connect into the system...below is my actual schematic of the current system.



All I was after was a way to join the two groups and plug into the other port on the 5500PC module OR a switch module that works just like an ethernet switch to plug the two separate groups in and then from there to the 5500PC module...below is all that I was after (page 10 excerpt from hardware manual originally linked by Froop)



So all I need to do is break each groups CAT5 wiring out to a terminal strip, matching the wires together (basically splicing them together) and running a single CAT5 from the other side into the single 5500PC port.

I have done the cbus toolkit programming and PICED HMI screens for the current system but am self taught and have had nothing to do with the wiring or phyiscal units, that was taken care of by electricians and a PM in another office in another city

I hope that explains it anyway, does that make sense to you guys and is that the correct way of doing it? (and please forgive me if I'm not using the correct terminology, as I said I'm self taught, I have no certificate or degree in CBus systems or software )

Cheers!

Craig

 

If you'd rather stick with all RJ45 terminated cables you could always go with something like this rather than using a terminal block to join them...

http://www.dse.com.au/cgi-bin/dse.storefront/4a41c4f0136bc3e0273fc0a87e01071f/Product/View/F2170

With the free topology of cbus cabling it won't care how it's connected so long as the cables are joined so these would effectively act as doublers for the rj45 ports on your existing modules.

 

Thanks Aridell,

If that's all that is required then that's exactly the type of simple answer I was after ...I guess at the beginning I thought because cbus uses a cat5 cable that it must need some smarts like a computer to communicate over it and manage signals.



I probably didn't help by making it sound more complicated than it was

Cheers!

Craig

 

It seems you have figured out what you want to achieve. But for the record, even if you don't realise it, what you were asking was indeed how to join two CBus wires together.

 

Sorry but I do realise (now what is required) but those pages only instruct and show cable polarity and pairing and jointing of wires from a single cable...it doesnt say anywhere in pages 20 or 21 that you need simply to join the same wires from TWO cables to join two separate groups of devices. One assumes when you see a cat5 port that it requires some firmware or driver to manage the comms of that port (I work with PCs, PLCs, HMIs and RTUs), therefore some type of device with smarts to link the two networks or more (as in network of devices, not separate cbus toolkit networks), not just be able to splice together midway.

What I don't get is if they went to the trouble to make it nice and tidy by using RJ45 connections why they didn't make a simple little adapter like the one from dick smiths or a cbus branded hub (or a bridge with extra ports so as well as extending a network you can branch others in with ease instead of having to fiddly wire them to terminal strips).

But thanks everyone for your help, I now have what I was after.

Cheers!

Craig

 

Craig - you have made another truck load of statements that indicate a scary lack of knowledge on C-Bus networks, wiring, comms, etc. Again I mean this in a nice way. After 15 years of working with this technology it is easy for me to say this.

It sounds like you have the opportunity to work with C-Bus so you possibly have a wonderful world of technical challenge and achievement in front of you. If this effort is not a "one off" take the tip and do some reading.

In reference to some of your last post items, C-Bus network cabling is a two wire system, forget the fact that Cat5 is used and Cat5 has 8 wires. C-Bus = 2 wires, for the Cat5 cable the recommendation is parallel up the first two pairs. Having said that, the spare terminals on an output are used for manual override - but let's not confuse the matter right now.

C-Bus = 2 wire system. That's same pair of wires for C-Bus power to units with C-Bus communications superimposed on top.

Now in previous posts of mine (sorry don't have time to link up the thread) I have made mention that the C-Bus protocol is so bullet proof that it will work on two bits of fence wire as long as you electrically isolate the two bits of wire. Now this started a whole string of posts that became outlandish and radical, like it should work over two bits of wet string etc. These guys are obviously nut bags because as anyone worth his salt knows if you use wet string you have to worry about keeping the string wet all the time otherwise you will develop comms issues. If those people pop back up in this thread ignore them

On a serious note - if you intend to work with C-Bus and do it justice, click on the links from FROOP and do some homework tonight.

All the best...

 

Hi Lucky,

Thanks for your informative reply and Froop also for your help. I will be delving deeper into cbus but at the moment I have other work to do, I am only spending a little bit of time programming some new dimmer relay modules for which the project manager (from another office in our company that I don't know a lot about - obviously dont have a cbus certified installer ) wasn't sure what to do when he had two cat5 cables and one port left on the PC interface module.

I think there's been a bit of presumption though (probably from my dodgy cbus terminology), that I don't know how to crimp two wires together and that im not aware of cable range or number of devices on the network limits (which wasn't even relevant to my question).

My question was how to join those two cat5 cables together so that I could then connect it to the PC module in the main switchboard. A simple answer of "join the same wires together from network 1 and 2 cables to a terminal strip then run a single cable from the terminal strip to the PC module" would have sufficed and got the job done...thanks to everyone for providing all the great info and reading material but I was after a tid bit of basic info quickly which the cbus tech person couldn't seem to understand either (or know the answer off all people) and it seems because I've spent at most a couple of weeks in total on cbus and don't speak your cbus language that you all think I have no idea what so ever...I simply don't know how devices communicate on this one technology! Don't think I am not grateful for your help, I just don't like the tone you guys are taking with me, yes I have a lack of cbus knowledge...I'll say again I'm self taught and haven't had a lot of time working with it.

Thanks everyone for all your time and help

Cheers!

Craig

 

Hi Craig,

Don't be offended by anything that has been said, quite often people come to this forum and ask rediculous questions, quite often without thinking anything through, and some of the experienced people on here can get very frustrated trying to answer some of those questions.

However, you do need to pay attention to what was said about cable length, network impedance, power supply/draw, etc... because if these things are not taken into account, and you simply join your two cables together, and all is not as it should be, it could cause network instability, or worse.

Everyone here knows that you're trying to learn and educate yourself, and nobody is going to try to stop you from doing that or think that they are better than you and therefore speak down to you. But you definately need to listen to what they have to say about checking things regarding your physical network before you join anything together.

If in doubt, and you have a large network, take the safest route, and install a network bridge, and learn how to set that up.

Also, take advantage of the training manuals available on the CIS website, and use the search function on this forum, as there is such a huge wealth of information on here, it boggles the mind.

Good luck with your endevour

Darpa

 

The simple thing to remember is C-bus is NOT CAT5, it is not Ethernet, it is C-bus. The pink cable it uses may look like cat5 but it isn't, it is special C-bus cable. Some devices have RJ45 connectors, but it they are just that RJ45 connectors and some devices simply have two screw terminals for the C-bus connection.

 

Hi Ashley W.... You're correct it's not ethernet but the cable is cat5e. The difference from normal cat5e is that it's been tested and has a mains rated sheath. This is so the cable can be legally run into mains rated environments such as switchboards. You must wherever possible, observe segregation rules when running mains and SELV cable however.

Cheers

 

Hi Dapra,

Yeah I was trying not to but after being repeatedly told to look at pages 20 and 21 as if I didn't know how to crimp two wires together and told a second time by lucky that I had a "scary" lack of cbus knowledge when I had already explained from the first time he noted that I did not seem to know what I was talking about, that I was self taught and have not spent a lot of time on cbus and no time what so ever on the wiring or physical installation of the cbus system, therefore I know I don't know a lot, you don't have to keep shoving that in my face no matter how nice you try to be about it...but that's beside the point, the electricians are the ones doing the work, I was simply trying to find some information to relay to them not take a crash course in cbus installation myself.

Ashley, it explicitly refers to the cbus cable in the manuals as CAT5...I know it is not ethernet but when you've worked with PLCs, HMIs, etc. you don't expect a connection that uses CAT5 as the communication medium to be so straight forward, your initial thoughts are that there will be some special module (like a cbus switch) to connect multiple sections of the network together.

The annoying thing is, all this could have been avoided if the PM simply read the bloody installation manual (or we had a certified cbus installer ).

I know it was a ridiculously simple bit of info I was after but without it, you are still stuck just like if someone taught you how to drive a car but missed the bit on where you insert the key...simple bit of information but still critical non the less and doesn't mean you are stupid or know nothing else about the system.

Am I right in saying you could use standard CAT5 to run between devices and simply run the mains standard cbus cat5 into the swichboard cabinet? (I do not know if this has actually been done, I have had no involvement in that actual installation remember, just curious)

Cheers!

Craig

 

Yes, this could/has been done. It's a much better idea to use the pink throughout so that if there is a requirement to join into the bus anywhere (another reason why the topology independence is great), you can be sure it's C-Bus.

Cheers