Some questions for BT guys.

[disinfo]

Hello,

First of all apologies in advance, this is going to be a hard to describe post!

Basically, we are in the process of moving into a new business premises. Somewhere between the previous guys leaving and us having some building works done, all the BT wiring has been literally ripped out.

The premises consist of an office building, and a separate workshop (separated by a yard)

I was trying to find the incoming cables today but have only had limited success.

From the pole there are two large drop cables, one runs to the far side of the office building (cut off and dangling in free air) and the other appears to terminate in a junction box at the other side of the office. There is also a grey 25 pair cable coming from this junction box back to the point where the drop cable has been cut.

In the Worksop there is also another 25 pair cable terminated in a junction box, this is goes to the pole via a Catenary.

On the dangling cable, I've been through all the pairs with my multimeter and found a single active pair, using a test phone I was able to dial 17070 and obtain the number (which doesn't correspond to any number that the previous business had)

The junction boxes seem totally dead.

Now for my questions (at last)

I was lead to believe that the previous guys had 2 ISDN phone lines installed. Would BT normally fully disconnect these lines hence the reason why I'm only picking up voltage on one pair at the moment? I'm wondering if this remaining analogue line was from a dedicated broadband line.

Also, would BT use one of their poles for customers internal wiring I.e. the multicore that goes from the office junction box to the workshop, if it was a BT business phone system?

Finally, what are BT going to think to all this? I don't know at what point this as all occurred , but we are going to need some lines by Feburary.

I'll probably have some more questions when I try to work through it all, I just wanted to get most of the details into this very long post!

Cheers

 

[SimonH2]

Basically, we are in the process of moving into a new business premises. Somewhere between the previous guys leaving and us having some building works done, all the BT wiring has been literally ripped out.

Not uncommon. If there's a clause about "reinstatement to as rented condition" in the lease, which is normal, then stripping out all the internal wiring would normally be required unless the landlord agrees to it being left in - which he would probably do if it was a good structured cabling installation that made the place easier to rent.

On the dangling cable, I've been through all the pairs with my multimeter and found a single active pair, using a test phone I was able to dial 17070 and obtain the number (which doesn't correspond to any number that the previous business had)

The junction boxes seem totally dead.

Now for my questions (at last)

I was lead to believe that the previous guys had 2 ISDN phone lines installed. Would BT normally fully disconnect these lines hence the reason why I'm only picking up voltage on one pair at the moment? I'm wondering if this remaining analogue line was from a dedicated broadband line.

Quite possibly.
With analogue, it's so likely that a future occupant will require service that they'll generally leave the line physically connected (until such time as they actually find they need the exchange port elsewhere). This does 2 things - firstly they can connect a new service without an engineer visit if the customer can plug a phone into the existing socket and call them from it; secondly it reduces teh amount of churn in the big patching bays at the exchange. The first is probably the main reason - it can save them a far bit of cash in engineer visits.
ISDN2 is different. It's a fairly low volume product and the next occupier is not likely to take it. As there are few imux ports in most exchanges, they'll almost certainly have disconnected the lines - probably just repatching them to the new premises if the customer has moved.

Also, would BT use one of their poles for customers internal wiring I.e. the multicore that goes from the office junction box to the workshop, if it was a BT business phone system?

Maybe, maybe not. If you were having a "BT System" then they may well do - especially if it's the only route. They would probably take a dim view of a third party doing it.
However, is this pole a BT pole ? It's possible (but unlikely) it's actually customer owned (ie a previous customer paid for it) if it's on private land and only serves these premises.

Finally, what are BT going to think to all this? I don't know at what point this as all occurred , but we are going to need some lines by Feburary.

A guy will turn up, pick a pair, stick his tone generator on it and go back to the green box to see where the other end is. Their records should show this, but they aren't always 100% accurate.

Just to complicate matters, it sounds like you aren't aware that there will be three different outfits involved - all "BT" to the man in the street.
BT Openreach are responsible for the cables between premises and exchange - as far as the patch frame I think. They are part of BT, but are (by law) required to be independent and offer services to all on an equal basis.
Then there's BT who provide the phone service. They rent the cable from BT Openreach, it's patched to their exchange port, and they provide the service.
Then there's a completely separate part of Bt that deals with phone systems.

For the latter 2, there are lots of alternative providers. For the phone service, these can either be "unbundled" (they rent a pair from Openreach and install their own exchange equipment), or wholesale (the service is still provided by BT equipment, but your supplier buys it from them wholesale and resells it).


BTW - I would strongly suggest avoiding analogue lines if you are having a phone system installed. Except for the smallest of installations, digital (ISDN) is far superior - "instant" call setup, multiple numbers, calling line identity (CLI), and biggest of all, no call collisions.*
* Call collisions are where someone calls in at the same moment that someone calls out. The person calling out picks up a line that has just had a call presented on it but where it's not made itself known by ringing the phones internally. You then have someone calling in who had the phone answered before it started ringing, and is speaking to someone who expected to be dialling digits rather than talking to some random person !

 

[disinfo]

Loads of really useful stuff

Thanks very much for replying, that's really useful.

BT wise, what I was hoping to do was to pull back the cable that I found the active pair on and terminate it into an IDC type box, then have BT provide me two ISDN lines and also an analogue line (for dedicated broadband and possibly fax also)

Would they be ok connecting to a clearly non BT IDC junction box?

Internal phone system wise I was going to buy something from the Internet, not sure what yet, I have some experience of Avaya stuff but that's about it. I want something that I can terminate directly to a standard CAT5e patch panel rather than a telephone DP, I'm installing four network points to each desk so I'd be able to patch directly from the voice panel to the structured cable patch panel. We are having a trench dug in with a separate duct for the comms cabling, so ill be able to run structured cabling over to the workshop as well and have a voice panel over there

I have a tone generator myself so ill have a look tomorrow whether the junction box in the office are the same cable (via the pole)

Thanks again for replying, I guarantee i'll have more questions!

 

[SimonH2]

BT wise, what I was hoping to do was to pull back the cable that I found the active pair on and terminate it into an IDC type box, then have BT provide me two ISDN lines and also an analogue line (for dedicated broadband and possibly fax also)

Would they be ok connecting to a clearly non BT IDC junction box?

Probably depends on the mood of the guy doing it. In practice, unless you give him reason to want to be awkward then there'll be no problem. Worst case is they'll redo it in their own box (or just swap the lid !).

Internal phone system wise I was going to buy something from the Internet, not sure what yet, I have some experience of Avaya stuff but that's about it. I want something that I can terminate directly to a standard CAT5e patch panel rather than a telephone DP

Good plan, you'd be surprised how many places I see with "structured cabling" which is only used for data, and separate phone cabling (I was working at such a site only a few weeks ago moving the "data" cabinet).

Some systems now have "RJ45" connections - great if you rack mount them, make sure you don't skimp on the rack height ! If not, then you end up with an MDF (large panel of IDC terminal strips) alongside the system and wired patch panels - that's what I did at my last place, about 400 ports worth (mix of SDX system phones, ISDN2, and analogue) on an SDX Index all wired to standard patch panels.

Cabling racks

• SimonH2
• 6 Oct 2011
• 3

In this particular setup, yellow patch leads are ethernet, green are telephony, and blue are...

This is the wiring to the back of some of the panels, and the wiring diagram I did so as not to mess it all up
Top row is all analogue, next row has analogue and digital, third row is digital and ISDN2, bottom row is all ISDN2.

Untitled

• SimonH2
• 19 Dec 2012
• 1

Untitled

• SimonH2
• 19 Dec 2012
• 1