Underground ethernet cables between buildings

[j17sparky]

I seem to remember reading on here that there are regulations surrounding using copper cables. Am i imagining things or are there? Any advice, links to government sites etc


The problem is we already have copper cables run between 2 buildings from years ago. 2 out of the 3 have recently failed, one last night. We also had a power cut last night - coincidence?

I have no idea what was done when fitting the cables, whether an electrician was consulted etc etc as it was around 6 years ago, well before i started.

:beer:

[StuartWhite]

Hi j17sparky,

Can I start by asking what you are trying to achieve here? Networking two buildings together?

If so have you considered doing this over Wi-Fi?
Ruckus wireless access points use technology called meshing, which literally meshes two or more access points together. I have set this up with a few clients and they love it.

However you may be trying to achieve something else, just thought i'd put the thought out there.

If you would like to talk more about this you can contact me on 07595718705.
I am on the road but will be in a meeting from 2.30 - 4pm

Kind Regards
Stuart

[j17sparky]

See first post ta. Thanks for the input and we may have to consider wireless if the problem does prove to be underground as id just love to ask the HT for money to dig up the school playground! lol

:beer:

[Geoff]

It's buried in the Building Regulations somewhere. I confess I have looked but have been unable to locate the exact section. Basically you are not allowed to connect buildings together with electrically conductive material. This obviously includes Cat6.

[StuartWhite]

Sounds great,

If you get to do it please post some pictures so we can all have a laugh

Rgrds
Stu

[ozzy]

How far are the buildings apart? we have ours connected with fibre optic cable tied to a catenary(30+ metre), also worked out very cheap using pre terminated fibre cables and stringing the catenary is'nt rocket sience.
might give you another angle to look at

[webman]

The discussion over copper cables being used underground is around the differing ground potential that the buildings could have. What about replacing with fibre?

[Geoff]

Also consider a laser link, microwave or ethernet over power.

[j17sparky]

Cheers so far people.

So geoff, do you think its against regulations then? Not that im doubting you but ive seen quite alot about armored cable specifically for underground applications. Obviously this doesnt mean it has to be inter-building but you are the first person i have found who has said in black and white "it is not allowed". Maybe its a newist regulation?

Just dont want to be going to SMT and telling them we need rid of the copper when we dont.

The discussion over copper cables being used underground is around the differing ground potential that the buildings could have. What about replacing with fibre?

In a perfect world id love to. Depending on where things terminate we might actually be lucky to get a fibre pulled through, we'll see. We've actually got most of the equipment already but we have no money. Got spare gbics on the nearest core switch, and we've got a couple of spare switches going. All we'll need is the fibre running and terminating, and 2 fibre modules.

Wireless - maybe it will be better now but the reason copper was installed was because too much interfearance was coming from the boiler house to get a stable connection.
Ethernet over power - most likely will have the same problems as above.

[webman]

In a perfect world id love to. Depending on where things terminate we might actually be lucky to get a fibre pulled through, we'll see. We've actually got most of the equipment already but we have no money. Got spare gbics on the nearest core switch, and we've got a couple of spare switches going. All we'll need is the fibre running and terminating, and 2 fibre modules.

I understand. If the pipe's big enough you could buy it pre-terminated.

[CyberNerd]

if you already have copper in ducting underground then it should be reasonably easy to tie a length of fibre to the copper wire and use the copper wire to pull the fibre through

[button_ripple]

We have a fibre cable at our school between our two buildings - no problems at all. It was supposed to be installed underground, but the school decided not to do it as it would be too expensive to fix if it broke.

We also have a CAT5e cable through a caternary to one of our mobile huts. I don't think that there is anything stopping that?

[Geoff]

So geoff, do you think its against regulations then? Not that im doubting you but ive seen quite alot about armored cable specifically for underground applications. Obviously this doesnt mean it has to be inter-building but you are the first person i have found who has said in black and white "it is not allowed". Maybe its a newist regulation?

Building regulations aren't really my area of expertise and are hardly 'concise'. Like I said, I know about this because our LEA pulled us up on it here. We have a science block connected via Ethernet cable.

webmans point about ground loops is correct. I've seen the same issue at a nearby primary school. It knocks out their main switch on a regular basis.

[CyberNerd]

We have a fibre cable at our school between our two buildings - no problems at all. It was supposed to be installed underground, but the school decided not to do it as it would be too expensive to fix if it broke.

not if you put it in ducting and leave a rope in there. Cheaper than that cherrypicker

[Geoff]

We also have a CAT5e cable through a caternary to one of our mobile huts. I don't think that there is anything stopping that?

All external building connections should be non-conducting. eg fibre, wifi, etc.

Also with a caternary, you have to watch the height, we can't use them for some building because the section of playground are counted as a 'roadway' for the purposes of getting a fire engine round the site. There's a minimum height requirement (basically about 5m) which is impossible to reach from a single storey building (It's in the Building Regulations and the Highways Act apparently) safely.