Metal enclosure with 3rd amendment.

[JohnW2]

... isn't one problem with that approach that it presents a risk of allowing the document to get seriously littered with all sorts of 'harmless but unnecessary' things - each proposed by one person, but with no-one else having a particularly good or strong reason for objecting?

Yes. It's perhaps not quite that simple, but I'm not a member of JPEL/64 so I don't know how rigidly the Chairman controls them. The reason for using consensus rather than voting is to stop minorities being frozen out by voting groups.

I can understand that, but a number of committees I've been involved with and/or have sat on, have at least partially addressed that concern by effectively defining the minimum size of a minority, whose view can prevail in the absence of objections. In other words, there is no requirement for a 'majority vote', but there is a requirement for some 'significant' level of support - maybe as low as 20% or 25% of voting members.

Kind Regards, John

 

[JohnW2]

Getting sort-of back onto eric's topic ...

Am I the only person who is 'less comfortable' opening up a CU with an earthed metal case than I am opening up a plastic one? ... and I say that a person who has a reasonably good idea of "what I am doing". I cannot help but think that at least some DIYers, particularly 'dabblers' and those who ignore advice given in places like this (or, worse, do not seek advice at all) are going to be at increased risk if/when metal CUs become more prevalent.

I still do wonder how extensive the 'change to metal' is going to be. Although we appear to be hearing about major manufacturers who have already decided to 'change', I wonder how many will come up with compliant non-metal ones, and to what extent they may be favoured over metal. I guess that only time will tell.

Kind Regards, John

 

[stillp]

A good Chairman will typically look around the room to determine a degree of agreement before asking if anyone objects. It's not the case that every proposal is accepted.

I would also be less comfortable working on a metal CU than an insulated one (although I have often worked on metal dis boards in the past). As for the take-up of metal, that will largely depend on how the manufacturers and regulators communicate with the marketplace. We are already seeing people assuming that all new CUs now have to be metal.

 

[Adam_151]

Getting sort-of back onto eric's topic ...

Am I the only person who is 'less comfortable' opening up a CU with an earthed metal case than I am opening up a plastic one?

Modern metal consumer units then no, I don't have the same un-ease. its all pretty well shrouded

However something like a Dorman smith loadmaster board then yes, plenty of exposed live parts and the cover weighed a lot, had non detachable door which also weighed a lot and would shift the weight distribution.

Federal stab-loks had a cover that you had to turn at a bit of any angle to try and not knock any breakers into the off position

 

[JohnW2]

Getting sort-of back onto eric's topic ... Am I the only person who is 'less comfortable' opening up a CU with an earthed metal case than I am opening up a plastic one?

Modern metal consumer units then no, I don't have the same un-ease. its all pretty well shrouded ... However something like a Dorman smith loadmaster board then yes, ...

It's certainly a lot better with modern metal ones, but what I said is still true - even with modern metal CUs, at some level, I still feel 'less comfortable' than with a plastic one. However, my second point is perhaps more important - at least a few DIYers (and probably even some 'electricians') will undoubtedly always do things within CUs which you and I would never dream of doing - and, for them, the presence of lots of earthed metal could surely increase the risks they were facing?

Kind Regards, John

 

[RF Lighting]

I've got a pair of plastic pliers....

 

[JohnW2]

I would also be less comfortable working on a metal CU than an insulated one (although I have often worked on metal dis boards in the past). As for the take-up of metal, that will largely depend on how the manufacturers and regulators communicate with the marketplace. We are already seeing people assuming that all new CUs now have to be metal.

We are, but I have a slight sneeky feeling that they might just get a significant surprise - maybe even to the extent that some manufacturers may have to 'back pedal'!

Kind Regards, John

 

[flameport]

These are non-metallic, and claim compliance with the new new standards:
http://www.doepke.co.uk/catalogue/Cat-pdf/conunits.pdf
ABS with tinted polycarbonate door.

 

[securespark]

I've got a pair of plastic pliers....

http://www.shutterstock.com/pic-395...-handles-on-a-white-background.html?src=&ws=1

 

[ban-all-sheds]

I wouldn't want a CU made out of magnesium

Or Wood's metal

 

[ban-all-sheds]

http://www.doepke.co.uk/catalogue/Cat-pdf/conunits.pdf

Good practice?

 

[ericmark]

Getting sort-of back onto eric's topic ...

Am I the only person who is 'less comfortable' opening up a CU with an earthed metal case than I am opening up a plastic one? ... and I say that a person who has a reasonably good idea of "what I am doing". I cannot help but think that at least some DIYers, particularly 'dabblers' and those who ignore advice given in places like this (or, worse, do not seek advice at all) are going to be at increased risk if/when metal CUs become more prevalent.

I still do wonder how extensive the 'change to metal' is going to be. Although we appear to be hearing about major manufacturers who have already decided to 'change', I wonder how many will come up with compliant non-metal ones, and to what extent they may be favoured over metal. I guess that only time will tell.

Kind Regards, John

You have made a very good point. I was working with another electrician who was saying how he left his last firm after a nasty accident. I am repeating what he told me and can't verify if true.

His mate was to fit a light in a panel. He fitted the light and wanted to get cables to bottom of panel to connect. He feed cables behind the mounting board but it would seem the main incoming cables had been damaged and when the cable touched the main incomer with damaged insulation ionisation happened and he was badly injured.

But it was what happened after which was the surprise to me. HSE it would seem fined him for not isolating else where and only using the isolator on the panel. Also his firm tried to recover money from him as well.

With domestic this would mean where the DNO has not provided an isolator then the fuse must be drawn before the cover is removed from the consumer unit. Clearly all turned off first so fuse not removed under load but this would present a problem with seals on the fuse.

I have been told the DNO should provide an isolator and where not provided it could be said it's a case of two wrongs but clearly two wrongs do not make a right.

I am sure like myself many electricians have gone into live metal panels and if the panel has been installed correctly there should be guards in place so even after removing the front there is no danger.

There has been many a talk about live working where to measure is not considered as working but where one suspects there is a fault in a consumer unit then it should clearly be isolated before opening and where one is called to for example an over heating fault then the only safe method with a metal consumer unit is to switch off the DNO isolator or if no isolator draw the fuse.

We as domestic do many things which as industrial we would not including working alone. OK the house holder may be there but they don't really know safe isolating procedure and it is questionable should we ever work alone?

I have had a phone call from another electrician XYZ has gone wrong could I get him an ABC as he can't really leave the panel open. Clearly he should have isolated else where but in the real world often we don't. Should this happen to a sole trader then he really does have a problem.

 

[ericmark]

These are non-metallic, and claim compliance with the new new standards:
http://www.doepke.co.uk/catalogue/Cat-pdf/conunits.pdf
ABS with tinted polycarbonate door.

There was quite a bit said about the hot wire test and it would seem the testing which was required is not good enough for the new Amendment 3 so unless it states compliant with Amendment 3 we really have no way of knowing if it complies or not.

The IET video shows use of plastic stuffing glands but at the lecture it was stated no one is sure if these will comply or not so until some guidance is given metal stuffing glands with the special rubber is the only way.

Even these

it seems will not comply as the lift up lid is plastic. This

looks OK but it's not a type tested consumer unit so OK commercial but not domestic I know manufacturers catalogues have them in but can you actually get one from a whole sale outlet?

 

[JohnW2]

These are non-metallic, and claim compliance with the new new standards:
http://www.doepke.co.uk/catalogue/Cat-pdf/conunits.pdf
ABS with tinted polycarbonate door.

There was quite a bit said about the hot wire test and it would seem the testing which was required is not good enough for the new Amendment 3 so unless it states compliant with Amendment 3 we really have no way of knowing if it complies or not.

If you look at flameport's link, you will see that it does say that the products are compliant with Amd3 (i.e. BS EN 61439-3).

Kind Regards, John

 

[AndyPRK]

Will the DNO now fit metal isolator switch enclosures rather than plastic. I expect not!