Different types of BT Cabinets. Why?!

This has been on my mind for quite some time. Why do bt have different type of copper cable cabs. Why couldn't they all be the same? Were they released in phases or did BT just want different types everywhere.

would be interested to know

fred

Because the network was built over many decades and designs change it that time

really, where i live there are 4 cabs. Two of them look likethis

Then, the other two look like this and this

please note these were all built roughly at the same time!

thanks for reply though

Over the years they improve the designs but the older ones will only get replaced if damaged or run out of space for more verts - the older ones still keep the insides dry so no point in replacing the shall.

Openreach are currently in the process of changing out the internal connections to a newer more water resistant version: https://youtu.be/2vapCCnNCz8

Some areas need the newer PCP shell to be able to be locked to stop theft of copper cables to/from the PCP.

If your roughly at same time spans 40 years one is a bery old design, one was the plastic and one is modern current style

The 1st image is I think the current PCP type, the second is the old PCP version, ours was the second type and has just had a new PCP cabinet installed about a couple of feet from it to as far as I know to replace all the insides as well as give it a new shell.
Now the 3rd image I have seen before but wasn't too sure if its a BT cabinet or not.

Paul

In reply to a post by MrSaffron:

If your roughly at same time spans 40 years one is a bery old design, one was the plastic and one is modern current style

Strawberry or Raspberry

Now the 3rd image I have seen before but wasn't too sure if its a BT cabinet or not

That's the cabinet which serves my home (cabinet 2, Danehill)

Thanks for all the replies!

Modern steel shell, cast iron, fibre glass/ GRP shell (70's or early eighties)
A shell ( the bit you see) may be replaced at any time due to damage, corrosion or expansion

In reply to a post by Ribble:

Modern steel shell, cast iron, fibre glass/ GRP shell (70's or early eighties)
A shell ( the bit you see) may be replaced at any time due to damage, corrosion or expansion

Well as you can see in this image we currently have two cabinets, the one on the right is to replace the old one on the left due to loads of line faults so I was told.

Not been round there in a while due to health reasons, so the old one may of been removed, not sure.

But looking at the one on the left in the image it doesn't look that bad to me apart from the odd bit of rust, so maybe its down to all the line faults its been having as late along with needing more space etc.

Also if you look carefully you can see cabinet 39 across the road (just in front of the council truck) which is the same as the new PCP cabinet replacing ours.

TBH I prefer the old cast iron cabinet due to if a car hits it the car is worse off, whereas the new ones just gets squashed and end up half a mile down the road.

Paul

In reply to a post by FredTheB:

please note these were all built roughly at the same time!

I think the answer is that they weren't. There may have always been PCPs there (although maybe not...) but in any case, the outer shells wouldn't have all been put there at "roughly the same time". When the oldest cast iron PCPs existed, "pillars" also existed - sort of an American fire-hydrant style, grey/white asbestos type arrangement, with a "vertical" contained inside. I think they are all redundant now but I know of a couple which (although redundant) physically remain. I think some were replaced with PCPs labelled something like PCP1(B), or similar.

On the old cast iron one there, which does look rather unusual (it's thin) - what is spraypaint-stencilled on it? And is the apparent "thinness" just a quirk of Google Maps and their car's view of it?

What I am asking you to do is take a photograph of it as best you can, and post it here, for my own satisfaction. It's got two doors so I don't doubt that it's an active PCP; but there are a lot of small, single-door cabinets which look like PCPs but are simply lightning surge protectors where a lot of lines are travelling a relatively large distance. Like the pillars, you can still see a lot of these hanging around in various states of disrepair, abandoned. I do know of one which is apparently active. The idea is that the cabinet doesn't ever change the network, but little carbon "fuses" get blown out instead of a massive power surge travelling further along that part of the network. I don't think they are part of OR's inventory any more, for several reasons, but others here will know for sure.

Edited by deleted (Tue 05-May-15 01:32:59)

Ok, its definitely still live, its definitely BT, there is no other 'replacement' cabinets and it actually serves pretty decent speeds for that half of the village. I will see what I can do for a picture, maybe get one tomorrow. Since this cabinet is receiving FTTC in the next few months, do you reckon that they will build a new pcp then?

Thanks

This the type of pillar you are talking about? If so, then they are much still in use as this is my SCP which the engineer was working on saturday.

In reply to a post by FredTheB:

Ok, its definitely still live, its definitely BT, there is no other 'replacement' cabinets and it actually serves pretty decent speeds for that half of the village. I will see what I can do for a picture, maybe get one tomorrow. Since this cabinet is receiving FTTC in the next few months, do you reckon that they will build a new pcp then?

Thanks

I'm not the perfect person to ask - but unless that picture has been squeezed by Google, I assume they might "re-shell" it - it will need extra "verticals" for the tie-ins to its new fibre twin cabinet. But again, others (i.e. actual OR engineers here) may know differently.

In reply to a post by WelshWArrior:

This the type of pillar you are talking about? If so, then they are much still in use as this is my SCP which the engineer was working on saturday.

Wow, yes. I didn't know they still used them! Just because of what's around here I suppose. The remaining ones are all abandoned and full of earwigs.

Edited by deleted (Tue 05-May-15 12:42:18)

Not sure why this one's still in use to be honest - probably just one they forgot about! The BT Engineer was very surprised when he saw it still being used - he assumed when he saw it on his paperwork that it was a mistake!!

In reply to a post by FredTheB:

This has been on my mind for quite some time. Why do bt have different type of copper cable cabs. Why couldn't they all be the same? Were they released in phases or did BT just want different types everywhere.

would be interested to know

fred

BT have different types of traditional PCPs because they have been installed all at different times. For instance new housing estates providing they are large enough will usually warrant a new PCP being installed.

Also if cabinets are knocked down by vehicles they are replaced with the newer design.

The old looking one next to 'Lucas Farm' in your third link is usually referred to as the old design; a cast iron shell - Pre 70s as far as I know. Despite what some people have said over the years on various forums, these are still used with FTTC in most areas I've seen. They are definitely built the best; if you tap one on the top you'll feel just how well it's built.

The plastic looking one is one of the designs that succeeded the cast iron cabinet.

And the current 'new' design is the one you first linked and as far as I know is built of very thin metal. It has existed since the late 80s/early 90s from what I've seen.

I guess it comes down to cost; it would be very expensive to produce the older cast-iron ones which have stood the test of time both materials wise and transportation wise - They are VERY heavy!

So yeah, basically it's because the copper local loop has been expanded over the years and new cabinets have also been designed to make it easier and more cost effective to install.

First picture is a Cabinet Cross Connection 6 - 1990s and 2000s
Second picture is a Cabinet Cross Connection 2 - 1960s and 1970s
Third one is a Cabinet Cross Connection 4 - 1980s

>>On the old cast iron one there, which does look rather unusual (it's thin) - what is spraypaint-stencilled on it? And is the apparent "thinness" just a quirk of Google Maps and their car's view of it?

It's a Cabinet Cross Connection 2, a smaller cast iron one than the classic CCC3.

The single door cast iron one is a CCC1

The Post Office Engineering Chief was persuaded to introduce cabinets in 1945.

Prior to that cables were all E0 and wall mounted cast iron and glanded plates called 'cable distribution heads' were used to divert pairs. Basicly a joint that you could access. Cable joints in those days were lead plumbed and labour intensive to re-enter.

These heads got into a mess as the wires were paper insulated and the paper fractured and wound itself through heavy intervention.

By 1965 70% of MDF pairs were connected to cabinets and it was easier to divert large main cables around cabinets than continually pulling cables out of the exchange to DPs. DP growth is notoriously unpredictable. In 1965 25% of residences had the phone and they were predicting 60% would have the phone by 1990.

So cabinets were all about flexibility, growth and labour efficiency.

So cabinets were all about flexibility,

Yep.

When I started, on the very first day, I was told by the trainer that the inbuilt flexibility of the BT (as was) network was one of its greatest assets.

Before cabinets, planners on average provided 11 main cable pairs per DP.

After cabinets the plan was to provide all DP pairs to the cabinet but crucially only 5 main cable pairs per DP.

So did labelling some cabs (e.g.) 1B just allow for local expansion before the telecomms world "blew up"? In some areas around here you have PCPs 1 and 2, and then 1B and 2B. They're the cast-iron type, clearly very old now.

I can see how it's hardly a mystery for anyone, just curious.

Edited by deleted (Tue 05-May-15 21:12:03)

I've never seen pillars labelled 1B, 2B etc. They are always designated 1/1 2/1 or E1 E2 etc in my experience. That's not to say it hasn't happened. Prior to 1992 the various 'districts' were run as pretty much autonomous businesses .

Here's a couple of other smaller types

an older one - https://goo.gl/maps/89W50
a new one https://goo.gl/maps/ir55G

In reply to a post by partial:

I've never seen pillars labelled 1B, 2B etc. They are always designated 1/1 2/1 or E1 E2 etc in my experience. That's not to say it hasn't happened. Prior to 1992 the various 'districts' were run as pretty much autonomous businesses .

Oh I only meant cabinets. I've never seen pillars numbered like that.

In reply to a post by troublegum:

...
an older one - https://goo.gl/maps/89W50

That looks exactly like a lightning-surge protector close-ish to here. Which, unhelpfully, isn't on Google maps/Street View.
Here's a disused one though. Another woodlouse/beetle-collector. I'm 99% sure it never was a PCP/Pillar. It probably got replaced with Hadleigh PCP 9, or EO lines from the Hintlesham exchange (which now has 2 PCPs and an EO re-arrangement). Or, as I believe, was always simply a surge-protector.

Here is a double-door BT cabinet which never seems to have served anything, at least in the last ~30 years (yes, sadly, I've looked). It's not marked at all and it doesn't fit into the numbering scheme.

BT ghost cabinets: Interesting, for more than one reason.

Edited by deleted (Wed 06-May-15 00:13:15)

Interesting that the Google Registration Plate Blurrer has not picked up on the very clear trailer plate, yet managed to locate the partially-obscured one on the towing vehicle.

About 1979 when I enquired about Domestic Lines, POST OFFICE telephones informed me that actual Domestic Penetration for England and Wales was about 65%; for Scotland it was 55%.

It was whilst objecting to the erection of a Phone Box outside my front door, about 10 years after this estate was built and every house had been pre-wired for phones.

When I checked in the Area Phone Book (quite small at the time), I found that 84% of the houses already had phones connected, from being listed in the Phone Book, thus probably installed at least two years earlier.

Walking round the estate, knocking at unlisted doors and enquiring, it turned out that only one house might NOT have had a phone, as there was no response at the door.

So around 98% of the houses were definitely already connected, with only one uncertainty; compared to the 55% officially for Scotland.

-------------------------------

It was then proposed to erect that box at another, younger, larger estate a little further out of town (a concrete base was actually cast in situ for this one); but the residents there objected - hence no Red Phone Box in this area.

>> Here is a double-door BT cabinet which never seems to have served anything, at least in the last ~30 years (yes, sadly, I've looked). It's not marked at all and it doesn't fit into the numbering scheme.

Could be an old trunk cabinet. They used to have cabinets with an electric supply and it was used for what ISTR was called capillary earthing. This was to stop current flowing on the sheathing of long distance lead cables causing corrosion.

Hey gazzyk1ns,

BT guy was doing surveys around the area and he told me the cab was from the Late 70s. He told me that he was looking to see if the cabinet needed a second PCP, but he said it would take him a couple of days to find out. He said if I look out for him tommorow, he will tell me what he thinks needs to happen.

Cabinet 1 in Banchory appears to comprise two cabinets, the oldest of which is this, which looks fairly antique. It actually now has been spray painted with �new PCP 100m �>� or something along those lines, pointing towards this cabinet. The new fibre cabinet was then built here, next to the phone box (in fact, I�m not sure if the phone box is even there any more).

It would be interesting to know if the old cabinet is still in use - I imagine the fact it's still there suggests it is?

It probably won't be. There's loads of old cabinets still lying about, which have been moved nearby and just left behind, empty inside.

If you look at 32:19 of today's BT Results webcast they show a slide of the inside of a 'copper legacy cabinet' and a 'next generation copper cabinet' - cheaper to make and install.. and a lot tidier!

Managed to get a picture for you guys of the cab you wanted to see more close up: cab pic

Heh, cheers for the photo. Google had "thinned" it a bit, i.e. their skewed view from the car-top camera and their continuity process made it look slightly strange. It's just an old, normal double-door cab.