Consumer unit reasoning

[Geordie Spark]

Right I'm away to a job, enjoy the (recurring and almost certainly circular) debate guys.

https://www.youtube.com/watch?v=aZdPCCKPDBY

 

[Geordie Spark]

Already been mentioned mate, better materials or design for the terminations.



Fike have designed a smoke bomb capsule for just this type of fire. Sadly it can not be installed in domestic properties. A domestic CU in the cupboard under the stairs full with coats and other combustible items, a smoke detector could save lifes and property.

The quality of the terminals - screws and tapped holes in busbars - are a biggie for me and I'm surprised there aren't more overheating/fire issues than there are.

Having "tradesmen" who can't tell when a screw is tight without the screwdriver making a clicking noise doesn't help much either!! :leaving:

 

[Silly Sausage]

I blame the ever decreasing number of smokers for all this.
It's who they (the Fire Brigade) usually blame fires on.

 

[Essex_]

So mains powered, interlinked smokes in houses, 1 near the CU and more elese where would be a better, policy IMHO.

Its not just CU's that catch fire in homes.

You know what. I would be happy with both as standard. Plus an emergency light near the cu.

 

[Essex_]

No they aren't, the regulation makes no mention of containing a fire it only requires that the box itself does not catch fire.
There is a big difference between being non combustible and being able to contain a fire!

The report specifically mentions the difference in CU that even with standard MCBs and no grommets still contain a fire quite well.

People trust us as electricians to give sound advice. Why can't we trust the fire brigade to give equally good advice?

 

[Essex_]

You've got to now accept that any reports/statistics coming from any of the interested parties that support the metal only stand, are going to be totally biased towards that end, you'll not be getting any real facts about the alternatives or those materials that conform to current fire retardant BS/EN Standards....

Well not until they start having to backtrack or do the about turns because they haven't originally thought everything through. Knee Jerk reactions generally throw up all sorts of unforeseen problems, that cause other knee Jerk reactions, and so it goes on!! It used to be called ''Management By Crisis'' and it tends to get to be a very expensive exercise when left to it's own devices....

Nowhere does it state metal only DBs.

 

[Essex_]

I really like that idea. Make it a reg on all new builds/rewires and CU changes to have a smoke detector within 3m of the CU. Easy and cheap.

Fantastic idea. I just have this feeling that certain people will be saying 'the regs are not retrospective, don't have to install them'.

 

[Essex_]

Its still not solving the problem of poorly manufactured CU's and idiots installing them.
You might as well invent a small capsule that you fit inside the CU's that breaks under heat. The capsule fills the CU with foam... Problem solved...

I don't think anyone is saying it will solve anything. It is a step in the right direction.

 

[Essex_]

Although, as I understand it, a CU is still allowed to have IP2X holes in the sides and bottom. Bit of a poor fire barrier!

This reg is not for stopping fires spreading completely but just to slow them down. Once the occupants are out - job done.

This is a life saving measure.

 

[Fin170]

A few years from now we'll have similar articles about metal consumer units from the ambulance service about a sky rocket in electric shocks from people attempting to reset the many faults on their 'Part p qualified' metal cu

calling it now

 

[UNG]

I hear you but reading the report I think the concern is also that in a domestic setting CUs are usually found under stairs and near front doors so generally a fire there would impede escape.

So why limit it to just the consumer unit when this is quite often co located with other electrical equipment contained in plastic housings that can affect escape routes

Its still not solving the problem of poorly manufactured CU's and idiots installing them.
You might as well invent a small capsule that you fit inside the CU's that breaks under heat. The capsule fills the CU with foam... Problem solved...

While the CU's may be poorly manufactured not all of them will end up bursting into flames so as you suggest those that do have other factors involved. There must be many thousands of CU's installed every year so the number installed that result in fires is only a small percentage the problem is the stats give no indication as to the age of the installation or any other factors that may contribute to a failure that results in a fire

The report specifically mentions the difference in CU that even with standard MCBs and no grommets still contain a fire quite well.

People trust us as electricians to give sound advice. Why can't we trust the fire brigade to give equally good advice?

With advice can come litigation and the fire brigade don't want to be in the firing line if the advice given is found to be incorrect

This reg is not for stopping fires spreading completely but just to slow them down. Once the occupants are out - job done.

This is a life saving measure.

There are any number of measures that could have been used to contain a fire why are under stairs cupboards not constructed with a double skin of plaster board to give it a 1 hour fire rating cupboards containing electrical equipment in escape routes could have a similar construction with a 1 hour fire rated door couple this with an earlier suggestion of putting a smoke / heat detector within the cupboard and you have a much better life saving solution

Containing and slowing the fire down has the potential for it taking longer to be detected and therefore giving no overall benefit to the occupants where escape routes are involved

If anything it was the building regs that needed to be reviewed and amended to accommodate better fire containment and detection for escape routes within domestic properties

 

[Engineer54]

Nowhere does it state metal only DBs.

Maybe, but you don't have to be a Phd to understand that is the overall intension of the CU amendment!!

 

[Essex_]

Maybe, but you don't have to be a Phd to understand that is the overall intension of the CU amendment!!

I disagree. I think there will be loads of non-metallic CUs coming out before Jan.

 

[Engineer54]

I disagree. I think there will be loads of non-metallic CUs coming out before Jan.

Of course you disagree, but then you change your mind with the wind!! At the beginning of this thread you couldn't agree more with the change to metal CU/DB's!!!

 

[UNG]

Of course you disagree, but then you change your mind with the wind!! At the beginning of this thread you couldn't agree more with the change to metal CU/DB's!!!

Been thinking the same with every thread he has posted in he swings both ways as he's frightened of missing something

 

[Octopus]

If the mandate for change included improved main switches and more robust internals then I would not have an issue!

 

[Essex_]

Of course you disagree, but then you change your mind with the wind!! At the beginning of this thread you couldn't agree more with the change to metal CU/DB's!!!

Again you are mistaken. I have never mentioned metal CUs. I said non-combustible. Why are you obsessed with metal? There are other materials that can still meet this new amendment. So I have not changed my mind at all. I fully support the change and always have and it will make zero difference to my day to day activities as an electrician.

 

[Geordie Spark]

Again you are mistaken. I have never mentioned metal CUs. I said non-combustible. Why are you obsessed with metal? There are other materials that can still meet this new amendment. So I have not changed my mind at all. I fully support the change and always have and it will make zero difference to my day to day activities as an electrician.

Asbestos should be able to meet this new amendment. After all it was used for flash guards inside CUs for years.

 

[Engineer54]

Again you are mistaken. I have never mentioned metal CUs. I said non-combustible. Why are you obsessed with metal? There are other materials that can still meet this new amendment. So I have not changed my mind at all. I fully support the change and always have and it will make zero difference to my day to day activities as an electrician.

I'm not mistaken at all!! We already have non-combustible plastic CU's, it's just they won't now tell you the manufactures, Tell me, why would they be testing non fire retardant CU's in the first place FFS for added effect for the promotion of metal CU's maybe? The article that so impressed you,was promoting the use of metal based CU's, NOT fire retardant Plastic CU's!!!

 

[Essex_]

I'm not mistaken at all!! We already have non-combustible plastic CU's, it's just they won't now tell you the manufactures, Tell me, why would they be testing non fire retardant CU's in the first place FFS for added effect for the promotion of metal CU's maybe? The article that so impressed you,was promoting the use of metal based CU's, NOT fire retardant Plastic CU's!!!

Exactly. We already have them. So use them. This reg is taking the choice away to use combustible CUs. It does not have to be only metal.

 

[Midwest]

Come on chaps, wants the point keep having these threads about Amendment 3 Consumer Units. You never gonna agree. What you have to accept is the new reg will be implemented next January. Three manufactures have already produced their efforts, and they are steel. The market for CU's is I expect small. How often do domestic properties have their CU's replaced? It's not like the iPhone market, so why would any manufacturer spend time, and more importantly their money developing a non steel CU. Note 1 says 'ferrous metal, e.g. steel', so why would they bother (and risk) manufacturing anything else.

 

[Engineer54]

Come on chaps, wants the point keep having these threads about Amendment 3 Consumer Units. You never gonna agree. What you have to accept is the new reg will be implemented next January. Three manufactures have already produced their efforts, and they are steel. The market for CU's is I expect small. How often do domestic properties have their CU's replaced? It's not like the iPhone market, so why would any manufacturer spend time, and more importantly their money developing a non steel CU. Note 1 says 'ferrous metal, e.g. steel', so why would they bother (and risk) manufacturing anything else.

I suspect the CU market is quite large, as there must still be millions of Wylex/MEM 3036 fuse boards out there, and why the sheds have been making a killing on twin RCD fully loaded CU's for a good few years now....

What risk is that?? The same manufacturers are supplying the rest of Europe with plastic CU/DB's. The market in Europe is many, many times greater than that of the UK!! They don't seem to be having any problems with fire retardant plastic enclosures...

 

[sammyshooter]

There's a great thread by D Skelton about the reg and it's actual application regarding non combustible enclosures, I'm trying to get a link but I'm pants with this app!

 

[sammyshooter]

Ok il have to copy and paste, but credit goes to D Skelton:

 

[UNG]

While were on the subject of combustible plastic how do these air freshener manufacturers get away with those horrible plug in things. Some reports in the past have suggested they were one of the biggest causes of domestic fires in recent years, yet I have never seen anything demanding that the construction of these be changed.
When I see them plugged in I always comment on them to the owner especially when the plastic is all brown and dried out and looks ready to burst into flames

 

[Midwest]

I suspect the CU market is quite large, as there must still be millions of Wylex/MEM 3036 fuse boards out there, and why the sheds have been making a killing on twin RCD fully loaded CU's for a good few years now....

What risk is that?? The same manufacturers are supplying the rest of Europe with plastic CU/DB's. The market in Europe is many, many times greater than that of the UK!! They don't seem to be having any problems with fire retardant plastic enclosures...

There's loads of 3036 boards out there, but people don't seem to want to spend their money on replacing them. They'll spend 10k on a new kitchen, but fall over when you give them a price for a new CU etc, and the old 'I can get a new fuse board from B&Q for £50'.

Take your point about the rest of Europe, but we are not in the rest of Europe, reg 421.1.201 is specific to the UK. So if BS7671 says, i.e. note 1 ferrous metal, e.g. steel, who is going to make it out of anything else. BS 7671 might not be statutory, but if anybody gets it wrong, your 'Michael Mansfield's QC's' will quote it word for word.

 

[rugbyspark]

Strange how all this seems to have happened since we've had "Part P" Pretend electricians !.
Could it be a coincidence ?.
Just checked out a commercial building on four floors with all S/O's well overloaded, multiple cores in 32A MCB's, some only just being gripped by connectors, some earth wires hanging loose AND inspection & test stickers from a big company in the last year !.
Now are we supposed to report these sort of items OR just let them burn ?.

 

[Engineer54]

There's loads of 3036 boards out there, but people don't seem to want to spend their money on replacing them. They'll spend 10k on a new kitchen, but fall over when you give them a price for a new CU etc, and the old 'I can get a new fuse board from B&Q for £50'.

Take your point about the rest of Europe, but we are not in the rest of Europe, reg 421.1.201 is specific to the UK. So if BS7671 says, i.e. note 1 ferrous metal, e.g. steel, who is going to make it out of anything else. BS 7671 might not be statutory, but if anybody gets it wrong, your 'Michael Mansfield's QC's' will quote it word for word.

It doesn't matter in this instance how much the CU costs, the market is anything but small!! I bet that the likes of B&Q will would also agree with me on this one too...

I gave you a more than a valid reason why the manufacturers of Retardant Plastic CU's are at little to no risk, as they are ALREADY (or should be) providing fire retardant plastic CU's that satisfy both BS and EN standards. But that's just the point isn't it, BS7671 is suggesting ferrous metal as an example, but does not give an alternative example such as an appropriate BS number for a suitable fire/flame retardant plastic.

Do you honestly think if such a case went anywhere near a court of law that a plastic carrying both BS and EN numbers for fire/flame retardant properties would get hauled through the mud? Especially when that same material is being used throughout Europe for virtually all CU/DB as well as many other types of electrical enclosures. Or the fact that the same material is being used by the DNO's for their service cut outs....

Jesus, ....talk about just rolling over!!

 

[Midwest]

Not in a position to afford legal advice, just my opinion. Expect the manufacturers have had though, and have decided how much money they wish to invest.

Crabtree....metal, Wylex....metal, Hager.....metal, Schneider....metal, MK....metal. There's a couple still sat on the fence. Don't doubt your argument, just think your wasting your breath.

I quite like the shape of the plastic CU's, only Hager seemed to have put any thought into theirs.

Jesus, ....talk about something else!!

 

[Engineer54]

Don't doubt your argument, just think your wasting your breath.

Thankfully, it's my breath to waste!! lol!!

 

[jonny705]

IHO I think these fires are more likely to be caused by the cheap nature of everything that you buy.
I have had crabtree sockets (which with MK used to be the best) that the switch contact blows out.
I have replaced 5 so far, none of them feeding a welder or something you could maybe suspect (although should they not be safely able to pull 3000w anyway?)

I had a Hamilton 3 gang light switch which I replaced 3 times before I gave up .
The manufacturers said I must have a high inductive load which was thus blowing the contacts out- I was like yes x4 21w under pelmet lights mate! - and it was not a cheap switch!

You used to be able to nibble through the buss bar on a consumer board,with a decent pair of side cutters, now the copper content is so low you need a angle grinder LOL!

Jeez when I go into Demans they must hate me, always moaning about how crap everything is, I swear even the cable now is less malleable , you only have to look at the earth wire in 1.0mm and it snaps!

But bottom line is, people like cheap hence China manufacture etc, but I think now a lot of bigger companies have bought back manufacture to UK because the quality control is so varied, plus China has put their prices up as well!

On an end note I have to replace a faulty RCBO today / tomorrow which i bought from Demans a few months ago, (keeps randomly tripping,) all at my cost.

 

[TJ Anderson]

On an end note I have to replace a faulty RCBO today / tomorrow which i bought from Demans a few months ago, (keeps randomly tripping,) all at my cost.

What brought you to the conclusion it is the RCBO at fault if it is intermittent. It is unlikely to be the RCBO, more like an issue out on the installation.

 

[jonny705]

Well I went back to installation , with original test results , re-tested everything on that circuit
( downstairs ring x4 d/s) give or take a couple of ohms was the same , as was IR and tripping tests.

Done a ramp test = 27mA .

Not supplying any outdoor stuff, no irons/fridges etc plugged in , only a digital radio and tv.

Was going to look at earth leakage testing gizmo, but TBH didn't know much about them.

So reverted to tried and tested heating engineer method of trial by substitution

Thus changed it for a 20A rcbo, as all i had on me.

Been in 3 weeks without tripping.

Just annoying, as customer tends to think you have screwed something up as new C/B.

Plus time /petrol etc, and cannot exactly charge client for a faulty new thing that I bought (like all the other times things like that have happened before , because of shoody Q/C .)

 

[Engineer54]

Was going to look at earth leakage testing gizmo, but TBH didn't know much about them.

I don't know how electricians these days can get by without a leakage clamp meter. As for you saying you ''don't know much about them'', leaves a lot to be desired....

 

[Deleted member 9648]

I don't know how electricians these days can get by without a leakage clamp meter. As for you saying you ''don't know much about them'', leaves a lot to be desired....

I dont have a earth leakage clamp meter,and dont intend buying one. Most EL is down to a low IR to earth,which I can verify with an IR tester. Failing that I can ramp test an RCD on load and off,if there's a difference with the RCD operating at a substantially lower current on load then there's leakage to earth. Unless I'm missing something here?If so enlighten me and I'll buy one. (On second thoughts I've managed for 35 years) !

 

[Engineer54]

I dont have a earth leakage clamp meter,and dont intend buying one. Most EL is down to a low IR to earth,which I can verify with an IR tester. Failing that I can ramp test an RCD on load and off,if there's a difference with the RCD operating at a substantially lower current on load then there's leakage to earth. Unless I'm missing something here?If so enlighten me and I'll buy one. (On second thoughts I've managed for 35 years) !

And how many of those 35 years were there RCD's present at virtually every job you went too??
Ramp testing is the poor man's alternative to a leakage clamp meter, some only ramp up in 3 or 5mA steps on the 30mA range. You could well be right about most or many leakage faults being down to low IR to earth, but it's those faults that aren't down low IR, and/or, being able to easily trace the source/cause of the fault, (including accumalative leakage problems) especially on the larger twin RCD CU's that make them a must have bit of test kit for today's electrician...

I bet i could trace an actual EL fault on a large 17th ed CU of any type, faster with just my EL tester, than you could with your MFT!!!

So Yep, it's time to purchase an earth leakage clamp meter, ...or maybe it's time to retire!! lol!!

 

[GEOFF S]

I dont have a earth leakage clamp meter,and dont intend buying one. Most EL is down to a low IR to earth,which I can verify with an IR tester. Failing that I can ramp test an RCD on load and off,if there's a difference with the RCD operating at a substantially lower current on load then there's leakage to earth. Unless I'm missing something here?If so enlighten me and I'll buy one. (On second thoughts I've managed for 35 years) !

They are very useful for Comercial/industrial applications.

Cheers

 

[Selfmade]

Not expressing an opinion for once, but for those who haven't found it yet, the new OSG has guidance on p84 for those making additions and alterations to installations with non-Amd 3 compliant CUs after the new regs come into force. It specifically states that installers should NOT advise replacement purely because the units do not comply. It also discusses some of the poor workmanship issues discussed on here. Nothing about the other design issues with the units themselves though.

Once again apologies if this has already been said.

 

[TJ Anderson]

They are very useful for Comercial/industrial applications.

Cheers

They are very useful in domestic too, I have used it so many times. Paid for itself many times over and makes me look even better than usual (and to be honest I look damn good even on a bad day). A good example of a recent triumph was my local rival (sworn business adversaries but also mates kinda lol). He had been to same job twice and admitted defeat. He could not find cause of intermittent fault and it would have killed him when realised I had been called there, although, fairplay, he hides his contempt well. Fridge compressor was at fault, but you would not find it on an IR test (he does not possess EL clamp). Needed to be powered and only when under load and relay switched over. TJ 1 - Rival 0. haha

 

[jonny705]

Regarding earth leakage tester,

I don't know how to use one , because I don't own one.

Simply because I have never needed one.

Any time I have been called back for a nuisance tripping fault 9 times out of 10 its been :

Dodgy item plugged in like irons , washing machines, extension leads to sheds/garages, any outside socket /light/ pond pump basically anything where moisture is likely.

Fittings being changed for fancy ones or moved for decorating and not done properly, (contemporary metal fittings that don't fit into normal back box depth,which squashes the wires which fall out, screws through wires etc..)
New Lights where there is not enough room to fit loop in/out/sw and again squashed in so they fall out.

If I disconnect circuit on a suspect RCD and the ramp test is less than 15mA I have just changed it.

This was the first time I had something that would have stumped me , as totally random and hardly any load, hence I started looking at buying an earth leakage tester and would have learnt how do use it , just like when I first learnt how to use an MFT,

I would not have give up until I had sussed problem out, and would have come on here to ask advise from people more knowledgeable than me, which is why these forums are so good.

If you think the attitude to admit I don't know something,
Am willing to buy new equipment and try and learn it,
And ask any one with better knowledge to better myself,
"leaves a lot to be desired...."
Well what can I say to that mentality?