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Posted By: Admin What's up with this? - 04/06/05 02:52 AM
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What's up with this?
All the clues are here in this picture.

- gideonr
[Linked Image]
Posted By: Admin Re: What's up with this? - 04/06/05 03:47 PM
more:

[Linked Image]

[Linked Image]
Posted By: Arend Re: What's up with this? - 04/06/05 04:19 PM
I see all fuses have a blue dot. I guess this is for identifing their rated amperage.

Maybe its overfused? The thick wire is on the same kind of "blue dot fuse" as the thin wire.

Here in Holland a blue fuse is 20 amp.

16 amp is standard for home installations. They are gray (as seen here [Linked Image]

<edit> Well, i mean the middle dot of the fuse has a color :-) Not the whole fuse </edit>

[Linked Image from supply-shop.nl]

- Arend

[This message has been edited by Arend (edited 04-06-2005).]
Posted By: gideonr Re: What's up with this? - 04/06/05 07:11 PM
All the fuseholders say 15A on them, but they seem to have the correct rated fusewire in them for the circuits they feed. Some sockets are wired with 6mm2 cooker cable, so more overwired than overfused. I guess that was the only cable they had to hand at the time. Good point, I was thinking of other things...
Posted By: Arend Re: What's up with this? - 04/06/05 11:01 PM
On a closer look, i noticed that all grounds are twisted together, but it isn't connected to anything.

All grounds are floating ??? [Linked Image]
Posted By: pauluk Re: What's up with this? - 04/07/05 12:05 AM
The grounds are pretty rough, but it looks as though they might be connected under the big wing-nut terminal on the upper left (exterior) of the box.

I can't make out if it's actually connected or not, but it does look like a ground runs from there (it meets up with one from the black MEM box to the left and they disappear out of sight below the meter).

That black MEM fusebox is also one of the old double-pole fused-neutral types.
Posted By: djk Re: What's up with this? - 04/07/05 01:11 AM
It's more a questions of "what is right with this?"

It's a shoddy, deteoriating mess and needs to be completely ripped out and replaced.

Why are there unsheathed cables coming out of the meter (the red ones - obviously ripped out of normal grey sheathed cable)

The main earth cable going back to the service fuse / bonding point looks way way too small. Given that this is a fused system with no RCDs or ELCBs a major ground fault could cause a fire as that cable doesn't look like it could handle 32+ Amps.

The rule of thumb here in the old days was that the earthing had to be capable of holding out until a fuse blew. i.e. capable of safely handling the load of the largest fuse + a safety margin for a good few secs.

There also appears to be a second bare earth cable going back into the terminal block / service fuse.
Don't the regs require bonding to neutral at one point and at one point only?

the fuse boxes look FAR older than the wiring too. I would assume, looking at them that they are pre 1950? Yet the cables look like they're from the 1970s. Why wouldn't the person involved have replaced the undersized and aging boxes?

Was the original conduit ripped off the wall? There appears to be at least one clip remaining.
Posted By: Trumpy Re: What's up with this? - 04/07/05 07:11 AM
Hey guys,
It's certainly great to see a few Non-US pictures popping up in here. [Linked Image]
Keep it up, you can either send them to Bill, Electure, or me. [Linked Image]
Anyhow,
When ever I see one of them old MEM Fuse-switch units, it usually means re-wire time.
We had a 3-pole unit over here at one stage that caused all sorts of problems, it was used out in the country.
It was designed to supply 2 phase 230V ranges.
One guy here was nearly burned severely when he plugged his razor into a socket that was fed from a range that had one of these feeding it.
Apparently, the guy that owned the house prior to him, had looped a plug off of the FS unit but had used the 2 phases (400V) and the neutral as the Earth. [Linked Image]
Guy plugged his Double Insulated razor in and (I don't need to explain the rest do I?)
Going by the pictures Gideon, where is the cable protection where the cable enter the Fuse-Switch unit?.
Having Basic Insulation showing (the wires themselves, as opposed to the cable sheathing) on a cable outside of a fitting or Switch-board is an Offence (Violation) here.
Also some clips on the cables above the whole thing wouldn't go amiss, as well as the Meter Tails.
What's with that wire leaving the bottom of the FS unit?, is it missing a bit of Insulation, where it goes around the side of the meter below.
Not a good piece of work at all!. [Linked Image]




[This message has been edited by Trumpy (edited 04-07-2005).]
Posted By: gideonr Re: What's up with this? - 04/07/05 11:19 PM
Yes, the grounds are just twisted together outside each of the boxes, with a green wire from the black box and a bare wire from the yellow go down to a commoning block along with the incoming neutral. Wires going in everywhere, no grommets or clips anywhere. The nut on the top of the black box holds the lid shut. Paul, it is one of them old fused both in live and neutral units, and I have a question: were they originally intended to be installed without protective earth wiring? There appears to be no provision for it.

I beleive the black box dates to 1954 when electricity was first arrived in the area, the yellow to 1969. I think the meter was also replaced '69 as there is the shadow of a backing board to the left of the black box. It surprises me that the South of Scotland Electricity Board (SSEB warning sticker on the wall) happily connected this lot up to service. The meter tails feeding the black box are fabric covered.

This is my parents house. I recently removed all the perishing rubber insulated cable in the rest of the house as that was especially urgent, this is second in line! Oh, and the water supply (from a spring) dates to 1860, cast iron and lead pipes...

Didn't anyone spot the burning under the second fuse holder from the left?

Gideon.


[This message has been edited by gideonr (edited 04-07-2005).]
Posted By: Admin Re: What's up with this? - 04/09/05 04:55 PM
more pics:

[Linked Image]

[Linked Image]
Posted By: pauluk Re: What's up with this? - 04/09/05 08:55 PM
This is certainly a mess and needs plenty of reworking.

Looking at those most recent pictures, it appears that the system is wired as PME (TN-C-S), so the bonding is definitely not up to standard. The feeder coming into the cut-out/meter board is also an unusual arrangement. How is this connected back to the incoming service?

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Paul, it is one of them old fused both in live and neutral units, and I have a question: were they originally intended to be installed without protective earth wiring? There appears to be no provision for it.
Many of those boxes had no specific earthing provision. In most of the places I've seen that used them, earths were just run outside the box to a block or terminal. (And remember that domestic lighting circuits of the era were seldom run with an earth anyway.)


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the fuse boxes look FAR older than the wiring too. I would assume, looking at them that they are pre 1950?
I'm not sure when that side-handle style unit went out of production, but if the place didn't get power until 1954, my guess would be that somebody used an old unit which happened to be on hand.

The other MEM unit though was certainly made right into the sixties, maybe even the early seventies. MEM seems to have been a favored brand by the electricians in my local area at that time, and there are dozens of these still in service.

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Yet the cables look like they're from the 1970s.
PVC-sheathed cables were certainly installed here from the 1950s onward. If they're Imperial sizes rather than metric (easily discernible by the stranding and tinned appearance) then they date prior to about 1970. Unless it's just the photo, those earths do look like bare copper though.


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Why are there unsheathed cables coming out of the meter (the red ones - obviously ripped out of normal grey sheathed cable)
Hard to tell from the picture, but they may not necessarily be unsheathed. For a time it was possible to obtain double-insulated meter tails which had the outer sheath black or red to match the inner insulation. (And as Gideon mentioned, earlier ones were rubber insulated with a fabric sheath, again of matching color.)

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Didn't anyone spot the burning under the second fuse holder from the left?
Didn't at first, but now you mention it, yes. It looks like the usual carbon deposits from a fuse wire which has blown fairly violently at some point in the past.




[This message has been edited by pauluk (edited 04-09-2005).]
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