how to isolate fuse box power

[plugwash]

unless there is a seperate isolator which there usually isn't you cannot isolate the complete fuse box.

With the main switch on the fusebox off everything except the incoming mains terminals in the fuse box should be isolated. Those termainals should be covered. It pays to be very carefull when opening it though because sometimes the covers for the incoming terminals are missing or the terminations are sloppy leaving live metal exposed.

 

[Pensdown]

a friend of mine has just fitted a shower and he has asked me if i can fit a fuse to his fuse box and also what amp fuse should be fitted.

Why did your friend ask you - are you an electrician?

 

[kkynaston]

lets get the story right then you all can finish having your laugh and move on to some other mug

Sorry, It's just that we have had some cracking posts here over the past months.
Anyway...

It really is a job for a spark. There are many important factors to consider. It is not just a case of sticking in a fuse. Have a search of the forums for installing showers, and the like. Maybe get your friend to read them

 

[ericmark]

Hang on chaps he makes a valid point if at work and not DIY the Electricity at work act is valid and this does stipulate to isolate else where. So if the supply authority has not provided an isolator then only way is the pull the fuse but the fuse has a seal so under The Electricity Safety, Quality and Continuity Regulations 2002 we are not allowed to remove the seal so only correct way is to call the supply agent and ask them to withdraw the fuse.
Yes I know that's not the way most of us do it but that is what should happen I would be interested to see what the LABC would require where someone has applied under Part P to add a circuit to a consumer unit as they are responsible for site safety and if they allowed anyone to open the consumer unit without isolating else where they would be creating a president and the old coal board case would then come in again. I think case law is really fascinating. I know as foreman any dangerous jobs I would do myself but I was warned against this because of this "By demonstration" case.
Remember the fuse is sealed for two reasons, one to stop or detect theft and two more important to ensure the correct size of fuse is fitted and because of the latter the supply authority can never give permission to withdraw the fuse.
Eric

 

[JACKC]

Having read through some of your previous posts and lack of good advice heeded by yourself, sparkies on here have no other choice but to laugh at you and your persistant attempts to kill yourself.
Do it any way you want as you know you shouldn't be doing it anyway.

 

[ericmark]

You say "Having read through some of your previous posts and lack of good advice heeded by yourself, sparkies on here have no other choice but to laugh at you and your persistant attempts to kill yourself.
Do it any way you want as you know you shouldn't be doing it anyway."
I haven't really advised on any course of action here have I? All I have done is point out it is a valid question to which I have no real answer. And with 30 years plus in the trade it was not my actions that nearly killed me it was the removal by another spark of my isolation lock and had it been my fault I am sure I would have not received the payout I got.
In industry the smallest breaches of health and safety could mean dismissal and had I removed a suppliers lock I would have been down the road yet it seems in the Domestic market often seals are removed and people get away with a rap on the knuckles and it is in the main because of this corner cutting that nothing has been done. I am sure if the supply authority was called out each time we needed to work on a consumer unit within a very short time isolators external to the consumer unit would be fitted.
Eric

 

[ban-all-sheds]

Hang on chaps he makes a valid point if at work and not DIY the Electricity at work act is valid and this does stipulate to isolate else where.

Can you expand on this?

Sounds as though what you are saying is that the EAWR 1989 require an electrician to pull the fuse or equivalent in order to fit an MCB into a CU.

Not something I've ever seen suggested before....

 

[ericmark]

Yes Ban-all-sheds that is what one is suppose to do. I would not for one minute expect anyone to do that, but again there was an accident in Brum where the electrician was asked to fit a light in a panel.

He switched off the panel at the panel and proceeded to fix the light connect cable to lamp then try to thread it down the back of the main plate to connect to terminal block at the bottom.

Unfortunately the incoming cable also behind the plate had been badly stripped back, and some insulation was missing off one phase wire.

The earth already connected to the lamp which was in turn already earthed to panel metalwork touched this and resulted in ionization and an explosion which throw the guy across the room breaking bones and causing burns and the accident was blamed on him for not isolating else where.

Until this I most likely would have done same myself. I worked with another electrician who had been on same job.

999 times out of 1000 nothing would go wrong and to me the fault was
1) not putting some insulation tape on end of cable before trying to thread. and
2) the original electrician for not repairing cable after nicking it.
But that was not finding of HSE who said it was guys own fault for not isolating else where.
I don't think this would ever happen with a consumer unit and just a little care and most of us could work in one without the slightest danger but if we follow rules to letter we should isolate else where.
Or wear all the goggles, gauntlets etc that the meter change guys are suppose to wear.
As I said I don't advocate that we all start doing that, but if we were to do by the letter of rules and regulations we should.
Just like you should apply hand brake at a stop sign. And I don't do that either.
po bodies nerfect!
Eric

 

[ban-all-sheds]

I don't think this would ever happen with a consumer unit

A domestic CU is indeed different to the type of board you described, particularly regarding the visibility of the incoming tails, which takes care of Regulation 14.

and just a little care and most of us could work in one without the slightest danger but if we follow rules to letter we should isolate else where.

No - if you follow the rules to the letter then isolating elsewhere is only required if it's necessary to prevent danger.