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Topic Title: 1 Cat 5 e cable
Topic Summary: for separate phone and broadband services
Created On: 22 January 2016 02:29 PM
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 22 January 2016 02:29 PM
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Zs

Posts: 3814
Joined: 20 July 2006

Hello chaps,

I'm going round in circles with a client here and I wonder if you could help? Its a block of flats, a conversion.

The specification (which I wrote) says;
Each apartment will be provided with Land-line telephone cable terminating in a single telephone socket outlet. The service will be capable of operating to make and receive calls without requirement for power.

For digital communications, each apartment will be provided with a terminated single broadband data cable outlet of Cat 5e or higher, suitable for broadband connection by the occupant to their chosen service provider.

Telephone and broadband outlets shall be connected via the site riser system to a suitable central control situated in the main service area. The contractor shall employ a communications specialist for the design and installation of all communications network services and specifically for final termination of accessories. If appropriate, installation of communications cables may be carried out by the contractor under the direction of the communications specialist.

this is now going round the houses like mad. The contractor is suggesting that one cate5e cable will do both perfectly adequately.

So long as the phone can be separate from the broadband provider, I can't get excited about how many cables.

But, connection to a broadband outlet uses all 8 cores from a Cat5 e doesn't it? Or has something changed and am I out of date?

I'm thinking one cable is not going to provide enough cores.

thanks,

Zs
 22 January 2016 02:42 PM
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mapj1

Posts: 9354
Joined: 22 July 2004

Depends what you mean by 'broad band connection'. If its an ADSL or VDSL line that will run back to the telephone exchange, its two wires, just like the plain old telephone service (POTS) .
In a domestic set-up the splitting of the line pair into low frequency audio (POTS) and high frequency data (ADSL) occurs in a filter box at or near the master socket, and the conversion of ultrasonic warbles into digital data occurs at a 'broadband modem'.

However if during the life of the building you expect things to advance to fibre to the basement, and Ethernet-like data to be created there, then a distinct twisted pair riser may be needed for that.

10 base T and 100 base T normally only need 4 wires, but 1000 Base T exercises all eight.

It is not wise to share telephone and Ethernet in the same cable, the result can be weird buzzing noises on the 'phone due to cross-talk.

ADSL and phone can share quite happily, and do, all 10km to the exchange in some cases.

So what kind of data do you have in mind ?

-------------------------
regards Mike
 22 January 2016 02:45 PM
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allaway

Posts: 218
Joined: 08 July 2007

Your requirement looks, to me, a little odd.

If we consider telephone service based broadband rather than a cable service (such as Virgin). This can be called FTTC, ADSL, VDSL

I will try and put it simply and short.

The telecoms service provider with combine both the voice and data signals onto the pair of wires from the distribution cabinet to the customer premises.

At the customer premises there is a passive splitter - the phone service is sent via a filter (to stop noise on the phone line) and the unfiltered sent to the modem (or hub depending on config).

That will ONLY need a high quality twisted pair - BTCW1308 or Cat5e.

The other option that BT can provide is FTTP or FTTH (Fibre To The Premises or Home) where they run a full fibre service to the building and there are other suppliers too. In the case of flats it may be useful if all fibre modems were in a central comms/facilities room. In this case you would expect to see a full Ethernet connection using Cat5e or preferably Cat6 cable from there to each flat.

100Mbit Ethernet uses just 2 pairs, full Gbit needs all 4 pairs.

Given that the ultimate goal is full fibre then you would expect to have two separate cable and NOT the phone service using part of the Cat5e cable. Suggest that the installation comprises 1xCat6 (4 pair) plus 1xCW1308 or Cat5e (2 pair); remember some people expect to have more than one phone too.
 22 January 2016 03:15 PM
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Zs

Posts: 3814
Joined: 20 July 2006

ADSL Mike, The construction has allowed for changes in the future if required and it was decided not to go the fibre route for now but there'll be room in the voids and risers if they change in the future.

Thank you for both of those replies. Most helpful.

Yes, I have two phone lines, one on the virgin media which I unsubscribed to because of the hidden costs and a BT one. Two cables, two sockets, two services. But 14 cores in total connected to terminals, hence the question.

I'm p'd with myself for not spelling that out more carefully or for not disclaiming it to a specialist in its entirety to be honest. Hey Ho. It's biting me on the bum.

Zs
 22 January 2016 06:08 PM
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arg

Posts: 148
Joined: 18 March 2015

One key question in all this is where the various kit is going to get installed - modems and BT NTE ("master socket") etc.

If you are talking about all the tenants contracting directly with their chosen telephone/broadband providers (and no common services provided by the management co. or whoever), then everything wants to get installed in the apartments - so there'd be no ethernet cabling in the risers. You really don't want each tenant putting their own modems down in the communal wiring cupboard with an ethernet cable back up the riser - apart from anything else, modems are commonly combined with WiFi and you don't want everybody's WiFi down in the cupboard (not to mention security issues, all this kit powered off the landlord's electricity... Nightmare!).

So for that scenario, you want a CW1308 to each apartment that BT are going to take over and put their NTE in the apartment. Phone and broadband go up a single pair of that cable combined and get split out at the NTE. Probably they'd be equally happy with cat5, but not with sharing it with other services. If you really wanted to, you could probably put the NTE down in the comms cupboard and extend it up through customer-maintained wiring (your cat5 cable) to the apartment, though I can't really see why this is a good idea.

If Virgin are an option, then the phone half is exactly the same as for BT (they will want a pair in a CW1308 and put an NTE in the flat), but they will also want a coax cable (I can't remember exactly what they call for, but it's something superior to typical TV antenna, they should tell you if you ask). This needs to terminate somewhere in the flat, usually curled up in a normal back-box with a blank plate over it - Virgin will then fit their huge and hideous outlet over the top if the user calls for it. Ideally you'd provide two of these coaxes - one to where the TV is intended to go, one to where broadband is needed - unless both happen to be the same place. Back at the comms cupboard, Virgin will install a (fairly compact) splitter to connect those coaxes together and back to their cable to the street.

So that's a requirement for 1off CW1308 (could use cat5 instead) and 1off or 2off coax.

The only case I can see for actually wanting another cat5 to take ethernet back to the comms cupboard is if there is going to be some kind of managed service - say the building management gets in a single fibre at very high speed and then splits it out to the tenants. That's a much more likely consideration in commercial buildings (serviced offices etc) than residential.
 22 January 2016 06:58 PM
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Zs

Posts: 3814
Joined: 20 July 2006

arg, thank you so much for taking the time over your post. Wow, this is indeed a specialist subject and I appreciate your input. This afternoon I suggested to my client that we have to get help and that this has become the blind leading the blind. He was most complimentary but the truth is that it has. In the past few weeks I have referred him to all sorts, have disclaimed, have told him I can't help and so on. I have referred him to those who set all this up for the tall blocks which I inspect (Hyperoptic fuses have been added to the DBs in nearly all of them and the TV splitters take up whole riser cupboards from a single 3A fused spur - I stop inspecting at the 3A fuse).

I'm happy that I have declared my lack of speciality.

I don't want to beat myself up too much because I spent a great deal of time over the specifications for this place and many of you would be delighted to have copies of such specs but what I will say is that I think, despite specifying a specialist, it needed to have more careful wording and bullet-proofing on the subject of the comms and data.

For the sake of somebody being able to google something obscure (like harmonics in the neutral conductor such as we do) at the same time as being on the phone to their Mum, this has become a sleepless night or two ahead.

I want my client to deliver to his occupants exactly what he envisaged for them. I fear I didn't know enough to write that part of the spec so I'm going to be asking you if you will trade sections of specs with me. I've got stuff here that you'd love to have but I didn't do so well on the comms bit.

I spoke to Atkins today 'when are you coming back Sal?' My self esteem was so low that I said 'Next week for Lunch with Andy and that's all'. Andy is having a rough time with a new PM so I'll go tell him some stories while my car is MOT'd. the edit: But on the other hand.. I just caught Jamie Lawson on the one show 'I wasn't expecting that'. Well I wasn't expecting to see a capo on the 6th and I can cover that number without a capo Jamie, so maybe things balance and we should not beat ourselves up too much in life? R&R will get that reference.

In the next life I'll stay in the kitchen and I'll learn to darn socks or something. I'm really worried that I've f'd up on this.

But It'll come out in the wash. Like jam on your T shirt does.

Zs

Edited: 22 January 2016 at 07:34 PM by Zs
 22 January 2016 08:27 PM
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Fm

Posts: 1710
Joined: 24 August 2011

I would have installed a plastic conduit from the flat to the riser with a draw wire to make it easy for the data monkeys
If I wasn't sure about a specification for another discipline , i would have simply advised - by others.

So were you doing the electrical works?
Or just specifying the job?
How many flats?
What type of riser?
What's the relationship between the client and Zs electrical ?
 22 January 2016 08:29 PM
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TeesdaleSpark

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 22 January 2016 08:46 PM
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nad

Posts: 396
Joined: 14 January 2005

Hi Zs,

It looks like your trying to spec the telecoms providers' infrastructure. I always leave it up to Openreach, Virgin Media, Hyperopitics, etc., to do their own designs.

Openreach (like the others I mention) free issue the contractor cable and ducting to install and pay a small fee for each unit connected.

The Openreach network (unlike the others I mention) is open and the Tenant is free to contract which ever telephone and broadband provider they prefer.

Regards,

-------------------------
Nad

*Regularly edited due to spell cheque misdiagnosis
 22 January 2016 08:56 PM
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nad

Posts: 396
Joined: 14 January 2005

It looks like you want a private Ethernet network for Tenants. Hyeroptics do provide such a network for blocks of flats, it might be worth giving them a call. Their network is closed- i.e. their cable (CAT5e, connected to Openreach leased fibre) can not be used to connect to another provider but that doesn't stop you having an Openreach (BT) line too.

-------------------------
Nad

*Regularly edited due to spell cheque misdiagnosis
 22 January 2016 09:00 PM
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nad

Posts: 396
Joined: 14 January 2005

Originally posted by: TeesdaleSpark

Have a look at these:



http://www.newdevelopments-ope...velopers-handbook.aspx


Thanks TS, I didn't have a copy of their Fibre Network Book.

-------------------------
Nad

*Regularly edited due to spell cheque misdiagnosis
 23 January 2016 12:16 AM
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mapj1

Posts: 9354
Joined: 22 July 2004

Err is this not just flats ? - surely they want a phone line or two for now, so they can have ADSL and stream TV, and enough empty pipe that optic fibre, coaxial cables or positronic neural data string can be blown pulled in as required by the demands of future technology as yet unknown - just leave the hooks in so it can be done.
Otherwise you risk equipping every room with the electrical equivalent of a speaking tube and a horn gramophone, and it may never be what is actually needed.

PS positronic neural data string does not exist. Yet.

-------------------------
regards Mike
 23 January 2016 12:22 PM
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arg

Posts: 148
Joined: 18 March 2015

Originally posted by: mapj1

Err is this not just flats ? - surely they want a phone line or two for now, so they can have ADSL and stream TV, and enough empty pipe that optic fibre, coaxial cables or positronic neural data string can be blown pulled in as required by the demands of future technology as yet unknown - just leave the hooks in so it can be done.


Indeed. This does sound like a situation I've encountered quite often, where the developer has asked for a "nice spec" to go in his brochure, when in fact if he'd just called for "the usual stuff" it would all have worked out better.

I should admit here that my experience is working on behalf of an equipment/service provider trying to pick up the pieces after the event - others above are more knowledgeable about how it's supposed to be got right in the first place.

However, on the coax issue, if Virgin are actually an option in the street in question, you do have to make things easy for them otherwise they will simply refuse to install. Professionally, I've had trouble getting them to come into blocks of flats, even when things were mostly right; personally, both my present house and my previous house they've refused to install despite their network being present in the street (in the current house, both my neighbours are connected but I can't because there isn't a duct to the boundary of my property).

Strangely, they don't seem to work on the basis of charging extra for difficult installs - if it's a development, you can work with them to build a business case that the multiple extra customers will be worth it, but if you are an individual end-user who has moved into one of these places they just don't want to know.
 23 January 2016 12:31 PM
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Fm

Posts: 1710
Joined: 24 August 2011

Put a plastic conduit in and a 1 gang box
Let who ever you want pull their cable and terminate.
Why make things so complicated
 24 January 2016 12:25 AM
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peteTLM

Posts: 3715
Joined: 31 March 2005

For a BT or virgin phone connection to each flat you must have a CW1308 cable as other have said, as they wont connect to CAT5 as part of their network.

Its also constructed differently

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