Networking between 2 buildings?

[ChrisC]

I would say that for distances around/over 30-40m, avoid cat5, because the signal degregation at those sorts of length is quite bad, don't even think about pushing 50+

 

Another advantage of linking building with fibre, is that if the building is high enough, linking cables from the rooftops is possible, with less risk of lightning problems.

 

Chris

[ajbritton]

Re Groundloop. Why not just earth the cable at one end only?

[plexer]

@Jake: You mentioned you don't trust cabling companies etc... at the end of the day if you know about what you are asking them then you are not going to be happy to be fobbed off.

 

I have a very good relationship with the cabling firm I use and their work is top notch.

 

Unfortunately we can't be experts in everything so we do have to put some faith in the experts when needed.

 

If you have more than 1 firm local or even not so local get them in ask them to quote you on the same thing i.e providing a solution to bridging your buildings and then compare the quotes.

 

Ben

[Jake]

Unfortunately we can't be experts in everything

Ben

 

So very true..hell if I was an expert in anything , I would be doing that for large sums of money. Probably even more so if I was an expert in cabling, bet I could earn wadloads being a cabling expert. Likewise servers, coding...pretty much any aspect of it really, if I was an expert at it, I wouldnt be a Technician in a school

 

I'm an expert gamer..but it doesnt pay too well

[Blanka]

Unfortunately we can't be experts in everything

Ben

 

Not strictly true, as there are plenty of IT newbies that are experts at screwing things up! If it wasn't for people like this people like us wouldn't be in employment!

[Geoff]

Re Groundloop. Why not just earth the cable at one end only?

 

Requires some electrical engineering doing on your switch. You'll need to unsolder the ground connectors on the cat5e port on the switch on one end.

 

Hands up who fancies that as an option?

[ajbritton]

@Geoff: Hang on, surely the earthing is only the shielding, which is not connected to anything. The actual cores are all twisted pairs and as such carry inverse voltages to each other. They then pass through differential amps to cancel out noise.

[plexer]

http://www.epanorama.net/documents/groundloop/rack_wiring.html

 

UTP will not cause a ground loop.

 

Ben

[Disease]

@Jake: You mentioned you don't trust cabling companies etc... at the end of the day if you know about what you are asking them then you are not going to be happy to be fobbed off.

 

I have a very good relationship with the cabling firm I use and their work is top notch.

 

Unfortunately we can't be experts in everything so we do have to put some faith in the experts when needed.

 

If you have more than 1 firm local or even not so local get them in ask them to quote you on the same thing i.e providing a solution to bridging your buildings and then compare the quotes.

 

Ben

 

Don't need to get quotes, Jake and I install everything ourselves, we do not subcontract anything.

[Geoff]

Hang on, surely the earthing is only the shielding, which is not connected to anything. The actual cores are all twisted pairs and as such carry inverse voltages to each other. They then pass through differential amps to cancel out noise.

 

Nope, that's just the shielding to prevent external EM from interfering. What I'm talking about is the internal ground wires in the twisted pair bundles causing cross talk because of the voltages travelling down them caused by the ground loop.

 

UTP will not cause a ground loop.

 

We're not talking about UTP. You'd never use unshielded twisted pair cable on an external cable run.

[plexer]

@Disease: So you have relevant test equipment and training to test your installations?

 

Ben

[Disease]

in a word, yes, don't you? I would have thought anyone running a large enterprise size network would at least a basic knowledge in how to install cabling for the said networks.

[ajbritton]

What I'm talking about is the internal ground wires in the twisted pair bundles causing cross talk because of the voltages travelling down them caused by the ground loop.

 

Ok, but could you not just snip the RJ-45 connector off one end and wire a new one up that does nothing with these ground wires?

[Jake]

Making a run from a cabinet on a 2nd floor, to a new IT suite on the 3rd floor, running to say 32 points (or whatever) really doesnt involve much more knowledge than being able to make up your own patch cable. Certainly I would think everyone here knows how to make a patch cable, so there isnt much problem in doing it.

 

We have testing hardware for the cabling runs, just to double check of course.

[webman]

Internally, the hurdles you may come across are finding the right path for cables to run, the right tools to make the right holes, and be aware of any asbestos that you may encounter on the route through.

[Jake]

Internally, the hurdles you may come across are finding the right path for cables to run, the right tools to make the right holes, and be aware of any asbestos that you may encounter on the route through.

 

We are lucky in that none of our buildings contain asbestos. The right path is not a problem, and we have all the right tools to make the right holes

[webman]

No problems at all then

[Disease]

Path!!!?

 

We have a drill that cost £899.99 if that helps.

[Jake]

No problems at all then

 

 

Indeed and beats paying several hundred quid to someone for doing something that I can do myself. Then I can use that several hundred for a nice shiny new laser printer heh

[plexer]

You may not run externally with UTP but you run your shielded stuff to patch panel which is then plugged into a switch by a UTP patch lead therefore you have no ground loop potential?

 

@Disease:

in a word, yes, don't you? I would have thought anyone running a large enterprise size network would at least a basic knowledge in how to install cabling for the said networks.

 

I never said anything about basic knowledge in how to install structured cabling I know how to do trunking, pull cables and terminate network cabling. But as I don't have a recognised industry certification or the relevant fluke or other make tester to test and certify my work I don't do it I pay the proffesionals. Plus that gives the 25 year guaruntee and someone else to call if it doesn't work.

 

Ben

[Jake]

Well, as everyone starts to siphon away and head home, I want to at least thank everyone for this thread today. Although it seems several tempers got a little more raised, its certainly helped to take my mind off the insane heat and help pass the time

[tarquel]

Just remember to get your P45 out if the wall falls down after drilling

 

[thus the reason why i dont drill walls here]

 

Nath.

[Jake]

Just remember to get your P45 out if the wall falls down after drilling

 

 

Nath.

 

LOL, our drill isnt quite that big, though sometimes I wish it was (aside from which I have been running my own cabling for 7 years now, so I tend not to drill willy nilly )

[plexer]

It's has been quie amazing how big this thread has grown today and we have had lots of opinions on the subject as well as going off topic slightly.

 

Ben

[Jake]

Indeed..and its shown just how different all of our roles and campus/limitations and environments are within whats, essentially, the same jobs.

 

Quite enlightening