Anyone can fix an MICC cable leading to a light switch in my house (London, N6)?

[Deleted member 148954]

Hello, I am looking for an electrician who has an expertise in dealing with MICC (mineral-insulated copper-clad) cables. It is a domestic job in my house (I live in Highgate, London; postcode is N6). When I was replacing a light switch in my living room, 2 out of 6 wires coming out of 2 MICC cables (which come through the wall; each cable has 3 wires) broke off. I am attaching two photos of the light switch in question (the 2 wires that have snapped are behind the switch). Please contact me if you can do the job and provide a quote. (If you need any further info, please let me know). Thanks, Eugene

 

[UNG]

Have never know MICC to be used domestically except as a sub main up a tenement building in Edinburgh.

Sometime around the I think late 50's / early 60's BICC produced the Octpus wiring system which was used for wiring flats I believe it had a central box and all the cables were terminated into it this was laid out on the shuttering and the cables laid out to there various positions before the concrete was poured. A friend of my mum worked at the BICC factory in Prescot terminating the ends on piece work and was paid something like 3d per end it doesn't sound a lot but they could terminate upto 20 ends per hour. I remember seeing the film at college back in the 70's and it was amazing how they did it

Around Prescot you quite often find the odd older house wired in MICC usually the owner or past owner worked at the MICC part of the factory or were a relative of someone who worked there

 

[ipf]

I

Sometime around the I think late 50's / early 60's BICC produced the Octpus wiring system which was used for wiring flats I believe it had a central box and all the cables were terminated into it this was laid out on the shuttering and the cables laid out to there various positions before the concrete was poured. A friend of my mum worked at the BICC factory in Prescot terminating the ends on piece work and was paid something like 3d per end it doesn't sound a lot but they could terminate upto 20 ends per hour. I remember seeing the film at college back in the 70's and it was amazing how they did it

A penny a minute, 5 bob an hour, eh?
Must have been in the fifties UNG, maybe early 60’s, though.
I remember the octopus, they used loads in 60’s high rise flats.

 

[ipf]

Why the insulated lugs with metal screws in the switch back box?

It's still not clear to me where, exactly, the wires have broken.

 

[7029 dave]

Never liked this type of MICC clamp switch box, they were always shallow not designed for dimmers etc.
The better way would of been to use full terminations Micc glands then pot and coupler and bush into a standard deeper box .

 

[ipf]

Never liked this type of MICC clamp switch box, they were always shallow not designed for dimmers etc.
The better way would of been to use full terminations Micc glands then pot and coupler and bush into a standard deeper box .

I agree.... but when that one was designed the best description of a household dimmer was a lamp getting towards the end of it's life.

 

[7029 dave]

I agree.... but when that one was designed the best description of a household dimmer was a lamp getting towards the end of it's life.

Never got on with them stupid clamp (on the pot) accessories. Used them once that was enough

 

[ipf]

Never got on with them stupid clamp (on the pot) accessories. Used them once that was enough

Hey up......look what I've found. A church attic littered with them.

Installed correctly, they had their uses, I suppose


.

 

[7029 dave]

Hey up......look what I've found. A church attic littered with them.

Installed correctly, they had their uses, I suppose


View attachment 101651.

View attachment 101650

Nah would look better with a glanded MICC and stop end box , more expensive but a quality job lol

 

[littlespark]

Orange pvc coated MICC…. Now that’s a proper job!

Fire alarms in red as well?

 

[Dustydazzler]

I am certain that Del used on of those pancake pyro boxes on a job when he had to repair a damage pyro cable is a garage

 

[7029 dave]

I am certain that Del used on of those pancake pyro boxes on a job when he had to repair a damage pyro cable is a garage

Yup he did, dont know why he didnt use full terminations into a conduit through box or AB.
Looks the bees when using PVC coated orange and shroud if you please. lol
Maybe Del could not source gland.

 

[UNG]

Nah would look better with a glanded MICC and stop end box , more expensive but a quality job lol

I have always thought those boxes made it look like a cheap job and wasted the effort exerted installing the cable, it's a bit more of a complete job when MICC is glanded looks more reassuring

Orange pvc coated MICC…. Now that’s a proper job!

Fire alarms in red as well?

When it was manufactured in Prescot you could get MICC with any colour serving you wanted if you were prepared to order the minimum quantity which was if I remember 3000m

When BICC manufactured MICC in Prescot they would even supply imperial sized glands and seals which were metric sizes drilled to imperial size

 

[littlespark]

I just remember years ago, it think it was going to be a museum or something... general power in orange, fire alarms in red and i think emergency lighting in white.

Apprentices jobs were to stand at the board and basically strip 2-3 foot off each cable as it came into the plant room.
Every day for a week coming home looking like Casper the flippin' ghost!


I think last time i even touched pyro was running a non-stop 500m length through the bowels of Ninewells hospital in Dundee.

There were more corridors under the hospital than appear above ground...

Spooky place sometimes.

 

[Dustydazzler]

I have only ever worked with bare and orange pyro

But I am certain I have seen white , grey and red pyro

I still remember clear as day being at a church we were adding some emergency lights and I came across pyro for the first time ( other than at college ) and my heart sank when I had to work on the old pyro circuit , but after a couple hours it wasn't too bad

 

[westward10]

As @UNG says BICC would produce it in any colour provided the quantity was cost effective.
I was also told 'Megger' every gland you make off. Strangely enough was in one of our local churches yesterday and whilst my girlfriend was signing the Queens condolence book I was scratching the MI cables to the light switch thinking they were painted grey but the sheath and shrouds were indeed grey.

 

[7029 dave]

As @UNG says BICC would produce it in any colour provided the quantity was cost effective.
I was also told 'Megger' every gland you make off. Strangely enough was in one of our local churches yesterday and whilst my girlfriend was signing the Queens condolence book I was scratching the MI cables to the light switch thinking they were painted grey but the sheath and shrouds were indeed grey.

Yup every pot you make off, I always IR the whole coil before installing so I knew it was ok.
Flag out your L with tape after both ends have been IR tested.

 

[UNG]

I think last time i even touched pyro was running a non-stop 500m length through the bowels of Ninewells hospital in Dundee.

Can't remember the last time I used pyro but I can remember one of the first times as a relatively new apprentice when an electrician and myself had to pull a 7L1.5 fire alarm panel repeater link across one of the Pilkington sites through the maze of underground ducts and cellars the run was about 850m and took us the best part of week to do

 

[Diddy]

Used to love the micc. Well still do but it is a rare beast today. As above test every end as you go. For surface stuff better looking at it than looking for it - Aka leave a good foot when you run micc in if you are doing a large job and wont make the end off anytime soon.
Anyone who tells you that they have never had an end down is simply a liar.
Pro tip lol check each coil quick ir test before running in 100 mtrs of the stuff.....A lot of time surfaced clipped on the add occasion that you come across a internally twisted coil...i have seen this maybe 10 times in 35 years.
The last english heritage sites I worked on (Roehampton) was ALL surface clipped bare micc probably 20 years ago, Don't know if it is the same now but back then EH insisted that all there properties were wired in micc
Finally Micc > FP anything.

 

[Sparky5473]

Funnily enough I only installed some micc last month, wired staircase lighting in a church tower using white pvc coated and ripped out some rough installed orange coated.

 

[littlespark]

What do you need two different strippers for?

 

[Sparky5473]

What do you need two different strippers for?

That was in case one of them didn’t strip very well but I ended up using just the joistripper as the blade was nice and sharp

 

[freddo]

That was in case one of them didn’t strip very well but I ended up using just the joistripper as the blade was nice and sharp

I use a cheap chisel sharpening kit to keep my joistripper blades in good order, the guide works well at holding the small blade firmly and at the correct angle.

 

[stevethesparks]

That was in case one of them didn’t strip very well but I ended up using just the joistripper as the blade was nice and sharp

A length of 1/4" rod bent over at one end for a handle with a slit in the other end to insert a slice of pyro was the best stripping tool.

 

[UNG]

A length of 1/4" rod bent over at one end for a handle with a slit in the other end to insert a slice of pyro was the best stripping tool.

Really depends on what size Pyro you are stripping the 1/4" and 3/8" rod is ok for the smaller sizes as you move up to the larger sizes for 4H16 and 4H25 I favoured a 3- 4ft length of 25mm conduit with a 90 bend at one end and a slot at the other end

 

[7029 dave]

I have never bothered with them stripping tools never got on with them.
Ringing tool and side cutters peels back just the job.

 

[LewisM]

Did you get it fixed mate or are you still sitting in the dark?

 

[Petej999]

Not sure if any member is close to you, but we will soon find out.

MICC is a fairly specialist area now. Not used so much nowadays as a new install.
If the core snapped right at the pot (I still know the lingo!) it’s going to need replaced.

Looks like it’s buried in plaster on a brick wall.

What do the switches control? If they’re all in the same room, likely solution is to have only one switch, controlling all lights and taking that length of cable out of circuit.
Or remake the end of both cables, bringing the switch up the wall a bit.
Or remake the cables high up on the wall, fitting in a box to use as a joint box with a blank plate… then extend in regular t&e cable back down to switch.


Have never know MICC to be used domestically except as a sub main up a tenement building in Edinburgh.
Was my brothers flat, and all the sub mains were bare copper MICC clipped surface up the stairwell. Amazing neat job.


Edit. Just saw Dusty’s reply….. Is that the celeb spark, Delroy? Love to see him work on MICC on YouTube… lol

I would need eyes on before I commit