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#109772 - 12/03/05 04:16 AM 2.5mm Cable fused at 100A
Out Of Phase Offline
Member

Registered: 11/02/05
Posts: 20
Loc: Wiltshire, England
Thought you guys might like this, I took this a couple of months back. This was found in the service cupboard of a block of apartments, the 2x small cables you see running out of that henly block are 2.5mm conduit singles, they feed a DB on the other side of the complex (50m+ away) with a heavy load on them, the fuse feeding these as you can see is rated at 100A...A fire waiting to happen.


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#109773 - 12/04/05 01:02 AM Re: 2.5mm Cable fused at 100A
kiwi Offline
Member

Registered: 12/04/04
Posts: 347
Loc: christchurch new zealand
Is the fuselink inside that 100A fusecarrier actually 100A or is it lower? Maybe the cowboy that ran the 2.5mm cable to the DB intended to "come back later" and put a 16A fuselink in.

What's the main isolator in the db rated at ?

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#109774 - 12/05/05 02:42 PM Re: 2.5mm Cable fused at 100A
djk Offline
Member

Registered: 12/26/02
Posts: 1269
Loc: Ireland
The whole installation is a total mess to start with.

It looks to me like some cowboy / DIY job was done on that. There would be no logic to add a connector block right after the meter.


My guess is the landlord / a "handyman" moved the panel without any idea what he was doing.

Surely that entire mess would fail an inspection, even without the 2.5mm circuit coming off the meter?

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#109775 - 12/08/05 03:00 PM Re: 2.5mm Cable fused at 100A
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Alex,
I'd have to go along with Kiwi on this one.
There must be a pretty small loading on that circuit or there wouldn't be much of the wiring left.
Is that SWA cable entering the bottom of that connection block?.
Looks to be a bit of corrosion below the Earth clamp.
djk is right though, this is a mess.
That largeish cable to the right of the chip-board sheet doesn't look very well installed or supported.
_________________________
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#109776 - 12/09/05 12:47 AM Re: 2.5mm Cable fused at 100A
kiwi Offline
Member

Registered: 12/04/04
Posts: 347
Loc: christchurch new zealand
How combustible is the chip-board that its all mounted on ?

Who connected that meter and how did this mess pass inspection ?

If that outgoing cable is 3 phase, shouldn't those incoming fuses (with the solid links) be a fused switch ?

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#109777 - 12/09/05 03:26 AM Re: 2.5mm Cable fused at 100A
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
 Quote:
Is that SWA cable entering the bottom of that connection block?.


It will be the old lead-sheathed cable -- Commonly used for urban supplies all over the country in the past.

 Quote:
If that outgoing cable is 3 phase, shouldn't those incoming fuses (with the solid links) be a fused switch ?


There's no main switch on the supply side of the meter, but the main PoCo fuses would normally fitted to that block. Why they've been bypassed and separate fuses installed is anyone's guess. (Presumably the yellow and blue phases disappearing off the top of the picture go to two more fuses.)

 Quote:
Is the fuselink inside that 100A fusecarrier actually 100A or is it lower? Maybe the cowboy that ran the 2.5mm cable to the DB intended to "come back later" and put a 16A fuselink in.


That fuse belongs to the PoCo and will (should) be sealed.


 Quote:
My guess is the landlord / a "handyman" moved the panel without any idea what he was doing.


That's sounds like it. I would guess there has been all sorts of gear mounted down the right hand side -- That gray box is an older-style MEM distribution unit. That Henley block probably had several sets of tails feeding an assortment of switch-fuses on the right, then somebody ripped it all out and connected that 2.5 subfeed.

Other parts have definitely been added to and modified over the years. Look at the earth clamp on the supply cable armor. There's an old wire to the earth block on the lower right corner of the board, but the heavier green/yellow earth cable is much newer.

 Quote:
How combustible is the chip-board that its all mounted on ?


It's a standard mounting method here. You'll see main switchgear and meters on boards like that all over the country.

 Quote:
Who connected that meter and how did this mess pass inspection ?


Everything on the supply side of the meter will have been done by the local PoCo. The wiring on their side is fairly typical.

No doubt the original wiring passed the basic PoCo tests (not a full inspection) when it was done many years ago, but the installation has just been hacked around since then.

Don't forget that until the new rules this year, there have never been any official inspections here.



[This message has been edited by pauluk (edited 12-09-2005).]

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#109778 - 12/10/05 11:52 AM Re: 2.5mm Cable fused at 100A
Out Of Phase Offline
Member

Registered: 11/02/05
Posts: 20
Loc: Wiltshire, England
Update,

It now appears that the electricity supply board did all the work, even putting the 2.5mm singles into that block.
The 2.5mm singles had 29 amps on them according to my clamp on tester, the fuse is 80A as I took it out and checked, I think the singles originally would have been run to a small switch fuse and then into that block, but appears that when this work was done that was just ripped out.
This feeder in the first picture use to be solely for the lighting and access control gear in the hallways, all the apartments had there own feed from the street. For some reason the Electricity board ripped all this out and fed every apartment from this incomer (probably so the landlord could terminate the supply to the apartments from one place)

Here is where those red tails run up too. Six apartments running off that incomer (2 on each phase) the black cables running out the top of those 100A fuses go to each of the apartments.



[This message has been edited by Out Of Phase (edited 12-10-2005).]

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#109779 - 12/10/05 12:14 PM Re: 2.5mm Cable fused at 100A
Out Of Phase Offline
Member

Registered: 11/02/05
Posts: 20
Loc: Wiltshire, England
To answer your questions:-

Kiwi - The minimum fuse you could put in that holder is 60A, there is no fuse at the DB end, just a switch, so no overload protection, and they have added seals on the meter and the henly block so I don't think they were planning to come back!

DJK - See above post with picture

Trumpy - See above post, it had 29 amps on it, the cables were warm but had not melted (luckily) The incoming cable is an old 4 core lead cable, these cables last forever (unless overloaded!)
That large cable is a 'split concentric cable" feeding a ground floor apartment, see previous post for a picture of where it goes.

Kiwi - Chipboard is OK, its commonly used for this type of install.
It was all done by the Electricity supply board, some of there engineers just don't have a clue! The Electricity supply board doesn’t inspect their engineers work.
That incomer with the label "existing fuse holders, now solid links" is there because they have added fuses above for each of the apartments, unfortunately that could put a 200A load on each of those red tails which are rated at 115A

PaulUK, your right, they do go to more fuses, see picture on previous post, unfortunately that’s 2x 100A fuses on each cable.

I think I've answered all your questions?


[This message has been edited by Out Of Phase (edited 12-10-2005).]

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#109780 - 12/11/05 01:16 AM Re: 2.5mm Cable fused at 100A
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Thanks for the extra photos Alex. It makes sense now, but what a mess.

 Quote:
It now appears that the electricity supply board did all the work, even putting the 2.5mm singles into that block.


You just can't get the staff these days.

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