Mineral Insulated Cable

[mevans12]

Hi

I'm not an electrician but am merely seeking some advice.

My property circa 1930's is wired with Mineral Insulated Cable. We are in the process of emigrating and wish to rent out our house, and understand that it’s wise to get a Periodic Electrical safety test done. The fuse box we have is old style with cartridge fuses, and has no trip (think RCD is the term?) switches.

Is it possible to install a new type consumer unit with RCD's without having to go to the expense of having a full re-wire?

Any advice re dealing with MIC and obtaining a safety certificate would be appreciated.

A friend also not an electrician has suggested installing a new consumer unit, then using the old fuse box as a junction box to connect the new consumer unit to the MIC. He did say that there was a risk that if any RCD picked up a fault it would be difficult to find. Any comments re this suggestion, or am I looking at a straight re-wire?

Many thanks.

 

[Deleted member 9648]

Have the installation tested BEFORE installing a new CU...not after and then finding RCD tripping issues. MICC is generally robust and fine if left alone and not subject to corrosion,there is no reason why your wiring cant be connected to a modern CU,but any decent electrician will be able to test and pick up any potential issues before carrying out alterations.

 

[Engineer54]

An MICC installation shouldn't need rewiring if in good condition, it'll outlast you in all probability!! ..lol!!

As for the CU, yes that would be a good idea. If you can post a photo or 2 of your CU, preferably with the front cover off, ....it will help us to advise you on your best course of action.

 

[trev]

Get the place tested then decide on your best course of action. My money is on the MICC being fine. Post up your location, one of our knights in shining armour (Well more like a grubby van) will no doubt come to your aid

 

[trev]

PS don't be told that you need a rewire just because your CU is old. It's a common "misconception" among the less scrupulous of us. Your test results will be the judge of that.

 

[mevans12]

Thanks for the replies and suggestions so far. Attached are 4 photos of the old CU and meter. We are in East Edinburgh if anyone fancies giving us a quote for this piece of work.

Thanks

 

[mevans12]

Thanks for your response. Have posted a few photos for you to take a look.

 

[Engineer54]

To be honest mevans, i can't see too much of a problem replacing this old MEM CU, for a modern equivalent. It'll obviously require a little more care removing the MICC cables from the enclosure, but nothing beyond an experienced electricians capabilities. Due to the MICC cables, it would be better to using a metal CU for your upgrade.

One point i would mention, is that you would do well to try and find an electrician that understands how to handle MICC cables, that i'm afraid would by definition exclude most of the younger electricians.

Oh and also ensure that ALL the other T&E cables entering the enclosure are suitably glanded into the the CU.... Looks like you will need to upgrade the meter tails while your CU is upgraded too. Any existing short cables can be extended within the new CU by means of permanent maintenance free crimped connectors...

EDIT.... Make sure you have the electrician that you employ inspect and test all the circuits before any work begins. I can't see your main earthing arrangement or any bonding conductors for your installation from the photo's you posted. So can't comment on whether or not you need these upgrading too.

 

[UNG]

I agree with the advice Engineer 54 has posted with just one note of caution

One point i would mention, is that you would do well to try and find an electrician that understands how to handle MICC cables, that i'm afraid would by definition exclude most of the younger electricians.

With a lot of the older generation retraining it is not just younger sparks who will not have experience of MICC how you identify the genuine from the bluffers is anyones guess

 

[ipf]

I agree with the advice Engineer 54 has posted with just one note of caution



With a lot of the older generation retraining it is not just younger sparks who will not have experience of MICC how you identify the genuine from the bluffers is anyones guess

I think E54 means young 'in the game' as well as in age. For example, a new Electrical Trainee would'nt stand a chance, a Electrical Trainee qualified 2 years ago might think they have.....but!

 

[Engineer54]

I think E54 means young 'in the game' as well as in age. For example, a new Electrical Trainee would'nt stand a chance, a Electrical Trainee qualified 2 years ago might think they have.....but!

I suppose i mean or talking about those that have never touched a bit of MICC cable let alone installed or worked with it!! Most of those will start panicking at the first glance of seeing MICC and decline the work. It's those that know nothing about MICC, but still take a chance and do more damage than good, are the guy's i'd be most worried about!! lol!!

Then come on to a forum such as this, ...asking how to remake a pot!! lol!!

 

[ipf]

I suppose i mean or talking about those that have never touched a bit of MICC cable let alone installed or worked with it!! Most of those will start panicking at the first glance of seeing MICC and decline the work. It's those that know nothing about MICC, but still take a chance and do more damage than good, are the guy's i'd be most worried about!! lol!!

Then come on to a forum such as this, ...asking how to remake a pot!! lol!!

Almost certainly imperial cable too. That might cause a few more problems. A great deal of care required eh. lol.
By the way, what's with the potentiometer? lol.

 

[Darkwood]

moving and messing with the glands can lead to their demise even when handled carefully, in this situe i would gut the fuseboard, fit a dinrail and use din connectors to extend circuits, stripping lid off old Dist Board and making new lid possibly plastic and tap and turn 4 lid screws, mark up as necessary then from there your options are straight forward (space permitting).
Its just one suggestion to avoid disturbing the micc glanding which could mean costly repairs or replacements, i also hazard a guess its all imperial glanding too just to add another chink in the armour, this could also mean old sockets , none standard boxes etc etc and as the list builds sometimes looking at a rewire becomes reality.

 

[robsparky1975]

ccc of micc a lot higher than t&e,and ive never seen on the forum a house wired in mineral,but it will need great care taken,if changed over,and out of interest what is the new colour cable supplying?

 

[Engineer54]

moving and messing with the glands can lead to their demise even when handled carefully, in this situe i would gut the fuseboard, fit a dinrail and use din connectors to extend circuits, stripping lid off old Dist Board and making new lid possibly plastic and tap and turn 4 lid screws, mark up as necessary then from there your options are straight forward (space permitting).
Its just one suggestion to avoid disturbing the micc glanding which could mean costly repairs or replacements, i also hazard a guess its all imperial glanding too just to add another chink in the armour, this could also mean old sockets , none standard boxes etc etc and as the list builds sometimes looking at a rewire becomes reality.

I don't agree with that at all, your making MICC sound like VIR cable which it definitly is not!!

Changing this CU should be no trouble whatsoever for an experienced electrician. Rewiring a MICC installation for an inferior system is just pure folly, and totally unjustifiable. All that is required is a little care when removing from the old CU and when installing to the new CU.

I have reworked old MICC cable to old industrial accessories and reconnecting to new many times, never once had a pot go down or split the sheath, ...and some needed quite a bit of reworking to fit the new enclosure... Bit of extra care Yes, rip it out because it's old, Not on your Nelly!!!