Melted Main Switch

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VonR

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A friend of mine posted me this picture of his consumer unit. It is a Crabtree Starbreaker unit professionally installed & certified in 2008. It has suffered a serious 'meltdown' of the MS. Anyone come across anything similar or willing to judge whether this is most likely:

a) manufacturing fault

B) potential installation fault

c) some other problem in the supply/installation

The pics were taken by the electrician that removed this and replaced it a couple of weeks ago - if you are on this forum, you will recognize it and be able to contribute further

und db.jpg

und ms meltdown.jpg

 
Yes - that's what you would think and still might be the case but the property owner (who is ex-pat living in Aus) received the following text from electrician that replaced the faulty unit:

"Main switch seems to have burnt out, dont thing it was a loose fitting connection as that is not burnt, only generally discoloured like much other.* looks as if the switch has overheated inside and melted surrounds, but rating is 100A.**Dont know if manufacturers have any comment"*

 
Don't like them busbars, funnily enough I was called out to a job yesterday, no power to downstairs ring. Started with the obvious at the CU, no power at the outgoing side of the MCB. Took MCB out to find the clip that it pushes into on the busbar, was loose. There were three the same, managed to find a spare way that was a tight fit and hey presto, restored power. Recommended new busbar at the very least.

First time I've come accross it but will think twice before fitting Crabtree gear now.

 
I suspect that those starbreaker busbars get too loose with multiple insertions. I doubt it has overheated because of an internal fault with the swich as most of the dammage seems to be in the busbar shroud.

 
I am the friend whose consumer unit it is !

The whole unit was installed new 2-year ago &, to the best of my knowledge, has remained undisturbed since that time. My tenant swears blind she never went near it. Nonetheless, it's puzzling what would suddenly cause this to happen.

Do you think it's wothwhile to get in touch with Crabtree themselves ? The whole place could have gone up in smoke after all ! Or, should I simply chalk it down to experience, swallow the cost of replacement & move on ?

Thanks.

 
Do you think it's wothwhile to get in touch with Crabtree themselves ? The whole place could have gone up in smoke after all ! Or, should I simply chalk it down to experience, swallow the cost of replacement & move on ?
Maybe worth contacting Crabtree, how helpful is the electrician who installed it? Is he a member of one of the Part P Schemes?

They quote a 1 year warrenty but you wouldn't expect this to happen, nor would they want the adverse publicity!

Good luck getting something sorted!

 
i'd go back to them, it can't be an installtion fault as its a push fit connection where the front cover should stop it from falling out completely.

the best i've had was a subbie fitted a new board and the left the property at 5pm, i was there to replace the board after the firebrigade left at 6-6:30 :)

loose tail, neutral i think it was. after having no electric all day when they guy left the tenant finally got all the things done she couldn't do in the day(washing machine, dryer, dishwaser, over for dinner, had a cuppa etc etc) and the board caught fire within 30mins of him leaving, unfortunate circumstances and just one loose cable, i always tighten tails and then check them again 15mins or so later and if still on site before leaving.

 
Thats quite worrying as we fit a lot of Crabtree Starbreaker boards, when I first saw the thread I thought loose conection or tails behind clamp when tightened, but it looks like a manufacturing fault to me :eek: CJS

 
I don't like those busbars either.

As Andy says you have no control over the quality of the connection. Nor can you check it or adjust it. Now, in theory, that is a good thing. I spent many years in my previous life (as a Professional Automotive R&D Engineer) designing adjustment and assembly variation out of all sorts of mechanical assemblies (mostly door systems stuff). And, in theory, it should be possible to design a plug together connection that always gives a good contact. However this is entirely dependant upon the quality of the design (the designer needs to have checked all variables in the manufacturing process to make sure that no tolerances overlap) and manufacture (the manufacturer needs to maintain quality and use all the usual tools to do so, eg SPC).

The trouble is that many industries simply don't pay well enough to get high calibre engineers who can do this stuff properly. On top of this we all know that Crabtree is CCC these days.

It's not possible to give an accurate analysis from the photos, but I strongly suspect a loose connection between the busbar and MS. As this connection is fixed and not adjustable by the installer then it can only be a manufacturing defect or design problem.

I would send the CU back to Electrium with a covering letter and a copy of the replacement invoice. I shouldn't mention it's a rented property (although I see that as irrelevant). Send the package by Special Delivery so you have proof of delivery and make sure to request a written reply within 14 days.

Take some more pics from various angles before sending it away and make a note of any manufacturing codes and dates on any of the parts (in particular look at the plastic moulded parts and look for a little "clock" with an arrow in the centre or some other info that looks like a date code). If you have one, use an ultraviolet pen to write your postcode on each part.

BTW: CCC = cheap Chinese cr@p

 
I am the friend whose consumer unit it is !The whole unit was installed new 2-year ago &, to the best of my knowledge, has remained undisturbed since that time. My tenant swears blind she never went near it. Nonetheless, it's puzzling what would suddenly cause this to happen.

Do you think it's wothwhile to get in touch with Crabtree themselves ? The whole place could have gone up in smoke after all ! Or, should I simply chalk it down to experience, swallow the cost of replacement & move on ?

Thanks.
IMHO it looks like a failure of the product, (most likely the push connection).

BUT....

the $100,000 question is..

Do you have a signed Electrical Certificate For the original install that would confirm that the product has been installed by a competent and qualified person?

An electrical certificate would have some test readings for the circuits such as Zs, which reads along the live (phase/line) conductors..

Through this push connection.

Good Zs readings would logically imply that when it was installed there was a good electrical connection at the now burnt out joint!

If NO certificate or readings are available... (although a bit of a long shot),.. It could be argued that the installing engineer/person/DIY didn't click push the switch fully home onto the bush bar? leaving a HR joint that has got progressively worse with time and use! :|

Was it installed by an electrician who was a member of one of the Electrical bodies? NIC / ECA / NAPIT / BSI / ELECSA ?

They may have tech support staff who may be able to offer a second opinion of the cause?

As long as you have Signed certs I would write a really stinky letter asking for explanations from Crabtree as to why their product has failed with possible horrendous consequences.

Considering they claim to have OUTSTANDING QUALITY? see here

http://www.electrium.co.uk/about_us.htm

And the quote from the above page:-

Crabtree, Wylex and Volex are renowned for their outstanding quality and excellent value for money. Specified worldwide, products are designed to satisfy the needs of specifiers, wholesalers, contractors and end-users in domestic, commercial and industrial markets alike, and are installed in many of the world
 
It looks like the spring loaded lock has come off which would allow the switch to dislodge itself over time from the busbar. I removed a switch from one of these the other month to run a cable up the back of the switch and it would not release then all of a sudden it did and the spring and metal clip when flying in bits.

 
It looks like the spring loaded lock has come off which would allow the switch to dislodge itself over time from the busbar. I removed a switch from one of these the other month to run a cable up the back of the switch and it would not release then all of a sudden it did and the spring and metal clip when flying in bits.
what!!!

and you didn't catch the bits!!!

tut tut Sir Ian!

thats a sure sign of a Lazy Spark!

A proper spark would have made a make-shift repair out of a pair of ladies stockings!

(oops was that Fan belts NOT CU main switches? :eek: :Blushing)

:^OROTFWLROTFWLROTFWLROTFWL

 
Firstly, thanks for all the replies.

To answer a couple of earlier questions, yes, the electrician who fitted it is NAPIT registered. At install he produced a multi-page installation certificate (Form 243 ?) comprising much that is totally meaningless to myself, but must no doubt be important !

This was all carried out in anticipation of renting the house out, so it needed to be done properly.

The guy who fitted it was a on-man-band & I'm not sure if he's still trading, but I'll see if I can track him down to discuss this.

I'll also contact Crabtree, but one key issue here is that I didn't buy it from them; I bought it from the electrician. So I can ask nicely, but I don't think I'm on very firm ground to pursue them hard.

Thanks all.

 
Sorry, I forgot to ask...

My letting agent rapidly arranged for a new consumer unit to be fitted to replace the damaged one.

Should I expect to see a new installation certificate (Form 243) &/or certificate of compliance for the new installation ? How soon after install should I be issued with these ?

Thanks.

 
Firstly, thanks for all the replies.To answer a couple of earlier questions, yes, the electrician who fitted it is NAPIT registered. At install he produced a multi-page installation certificate (Form 243 ?) comprising much that is totally meaningless to myself, but must no doubt be important !

This was all carried out in anticipation of renting the house out, so it needed to be done properly.

The guy who fitted it was a on-man-band & I'm not sure if he's still trading, but I'll see if I can track him down to discuss this.

I'll also contact Crabtree, but one key issue here is that I didn't buy it from them; I bought it from the electrician. So I can ask nicely, but I don't think I'm on very firm ground to pursue them hard.Thanks all.
IMHO by Tort law you did buy it from them as they manufactured the product

and they have a duty of care to the users of that product!

http://www.wisegeek.com/what-is-tort-law.htm

e.g.

If I had purchased a second hand Toyota off my friend 8 months ago..

and the accelerator pedal stuck!!!

It is Toyota's responsibility not my friend who I bought it off!

Just as the Electrician who supplied the product didn't make it.

it was Crabtree!

Provided the product had not been modified and is installed in accordance with manufactures instruction and current wiring regs they have legal responsibilities toward their product irrespective of which route it got you.

;)

 
Sorry, I forgot to ask...My letting agent rapidly arranged for a new consumer unit to be fitted to replace the damaged one.

Should I expect to see a new installation certificate (Form 243) &/or certificate of compliance for the new installation ? How soon after install should I be issued with these ?

Thanks.
YES new consumer unit requires new Electrical installation certificate

AND

a building regs compliance certificate..

as the work is notifiable under Part P building regs. :)

 
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