Ageing electrics

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I have an old house with an electrical installation which must be at least 30-40 years old in places. Porcelain fuses, many bakerlite junction boxes, switches etc.

In the process of saving for a total re-wire but have had to have a little patching up to do now and again in the meanwhile. All been fairly simple stuff to date, remove appropriate fuse install new switch, re-wire and re-insert fuse etc.

However, I now have a far more immediate and complex task.

There is a submain switch which which has blown in some style, Its a Wylex 104 and supplies the shower in the bathroom upstairs. I have identified and rectified the short in the bathroom, which was a screw shorting in a junction box. It has taken out both the switch and the 45 amp fuse, frying some cable in the process.

20220517_073112.jpg


Problem is that the switch is supplied direct from the meter so there is no way of isolating this.

I know ... I know that I need an pro for this, but my fear is that he'll look at the rest of the installation and just walk away. I am half way to my £5K target for a complete re-install and just need to buy a little more time but will need to take a shower while waiting. I have a couple of other less important circuits with un-identified issues and have simply removed the fuses to ensure they are no longer live.

Really need a little help here, not necessarily in how to do this myself, because I no I should not attempt that, but maybe how I might convince a spark to provide a temporary fix.

For re-assurance this is in a locked cellar and there is only me living in the house, so the existing blown switch/fuse is presently secure.
 
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Correct - lock wired. Was reluctant to remove.

I'll take a photo and post it tonight.
 
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Given the age of the wiring it is likely that the cut out and main company fuse are also very old.

Pulling the fuse on any cut out is hazardous, pulling the fuse on an ancient cut out can ( and has ) resulted in the fuse holder falling apart and creating a short circuit on the incoming supply. The incoming cable can then burn like a roman candle.

The fuse at the sub-station will be at least 200 Amp creating 50 kW of heat energy at the short circuit but also could be 400 or higher,

Pulling the main fuse is NOT a DIY task
 
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Given the age of the wiring it is likely that the cut out and main company fuse are also very old.

Pulling the fuse on any cut out is hazardous, pulling the fuse on an ancient cut out can ( and has ) resulted in the fuse holder falling apart and creating a short circuit on the incoming supply. The incoming cable can then burn like a roman candle.

The fuse at the sub-station will be at least 200 Amp creating 50 kW of heat energy at the short circuit but also could be 400 or higher,

Pulling the main fuse is NOT a DIY task
Will post more photos this evening.

Don't worry..... I have NO intention of pulling the main fuse.

Just noticed your profile !

My place is old, but not 510 years old :D
 
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Bernard has posted his advice before and it is the reason behind why I asked for a picture of the meter setup, some are more than capable of being done diy and have been done by both diyers and qualified sparks many times.

Others are a fire waiting to happen, you need to be able to judge the situation for yourself before considering doing it.
 
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Just as an aside..... The supply to the house runs beneath a neighbours back garden, about 30 yards away and the cable isn't much thicker than a fat finger.

A couple of years ago they were having a kitchen extension and uncovered the unprotected cable while digging. Unsure what it was, the builders just put a spade through it and removed about 4 or 5 yards of cable without thinking about it. Totally cut me off. They could have fried !!

Got them to sort it once it was discovered where the problem with my supply was, but it gives you some insight on the sort of stuff we have to deal with. .... Wouldn't mind but this is all within 3 miles of Manchester City Centre.
 
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Personally I suspect the overheating is unrelated to the blown fuse. The fact it's localised to one terminal strongly suggests a bad connection.

In any case that CU needs to be replaced. The problem is the cable feeding it also looks questionable, T&E isn't really suitable for connecting to meters.

PVC cable that has not been abused and did not have manufacturing defects can last a bloody long time, there is still plenty of cable installed in the 1970s and 1980s and perhaps even the 1960s that is still good. Rubber cable is another matter, the general advice is not to touch it until it can be rewired.

We really need pictures of what's going on around the meter and other CUs to advise further.
 
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Those wider shots confirm my fears, you appear to have a very old (rubber era) installation that has had additions poorly bodged in.

Unfortunately I don't see a lot of good options, a rewire is clearly needed but you say you don't have the money for it right now. I can't advise you to pull the service fuse yourself (though if you *must* do it, then at least turn off all mainswitches first so no current is flowing) and I agree you may struggle to find an electrian who is prepared to work on the installation in it's current state.
 
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at least 30-40 years old in places.
More like 60-80 years. Rubber insulated cabling hasn't been in general use for building wiring since the early 1960s, wooden fuse boxes with ceramic fuses are latest 1950s, and more likely 1940s.

There is no quick fix for that destroyed shower supply. If the cabling to the shower is in good condition, absolute minimum would be to install a small shower consumer unit with RCD, install main bonding to the water and other services, remove that mess of cabling from the meter and install new single tails from that to connector blocks, which would connect to the new shower unit and the rest of the old junk.

It's all in a dangerous condition, and should have been removed decades ago - as in it was due for replacement in the early 1970s. There is a very real risk of fire and electric shock.

If it's really essential for it to continue in use, the installation of an RCD such as 100mA or 300mA to cover the whole lot should be considered, assuming there aren't already faults which would trip one instantly.
Or just have someone disconnect everything, install a small consumer unit and 8 double socket outlets either there or in a central position and use extension leads to whatever items are needed, with some plug in lamps for lighting.
 

bsr

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Is it just me or does the cable from the meter to the shower isolator look to have been cut? It just sort of stops.

....

....

However the risk is that you touch the black rubber cables and they fall apart as you try to move them into the CU.

If you don't have the cash, how about getting a new CU and a basic installation using surface mounted trunking to keep the costs down? Or do all the chasing and making good for the electrician.
 
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