Shower RCD or new CU?

[ukants]

Hello all,
I'd like to add RCD protection to my electric shower but can't decide which way to go about it.
At present my CU is a Wylex 6 way, old rewire fuse job that I've converted to MCBs (1 way not used), so the shower is protected by a 32A MCB but no RCD. Am I right in thinking that Wylex don't do plug in RCDs and so would I fit a 63A 30mA RCD (like this: http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=A331831&ts=06724&id=90026 ) just after the 32A breaker? Would this be notifiable to the LABC?
Alternatively, I'm thinking about completely updating my CU to a split load version but not sure if I'd be spending money for no reason, as I've no garden so it's unlikely an indoor socket will be used for outside appliances. I'm in my second year of the C & G 2330 and, if I go down this route, would like to do the change myself, once I've notified the LABC, but would I be allowed to? Or does a CU change still have to be done by a fully qualified sparky regardless of notification?
PS...just like to express my disappointment that United Utilities who run the supply in this area refuse to add isolation switchgear between the service fuse and the CU...which I was quiet willing to pay for . Is this the norm now?

Regards,
Ukants

 

[PompeySparks]

It's good that you want to go down official channels with Building Control...

I have to warn you I have read about five posts recently with different building controls in different areas applying different rules!

Hopefully, you'll have one of the more co-operative BC's!

EDIT: One BC I heard of would not allow the customer to change a CU by themselves because the BC did not consider them competent - another was happy for the customer to do it as long as they got a competent Electrician to certify it!

 

[Adam_151]

The first thing to do would be to speak to building control and see how they deal with notifications, some have a habbit of being arkward gits, though most of them would probably be happy to accept an EIC from you (might insist that you have 2391... but that doesn't take very long to do, its a much shorter course than 2330)

As for the actually job, if you did the extra RCD after the fusebox you'd be limited to 30A which would mean a very poxy shower.

So I think its either a CU change, or henley in something like this : http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=A331829&ts=31265&id=42858 next to the existing CU

As regards to Isolation, when you get it isolated (however you do it) fit you own isolator, as to getting isolation, you can either

A) See if you can get a REC meter monkey to remove the fuse, let you fit your isolator and refit it

B) Pull the fuse yourself and the seals were cut before you got there by the fuse fairy

C) Pull the fuse youself and fix the seal afterwards with a dot of superglue

D) if you have balls don't bother with isolation (not recommended!!!!)

Remember if you pull the fuse, to kill the load on it first

EDIT : WTF @ me (Opposed !=regards) (posting when drinking is bad m'kay...)

 

[PompeySparks]

Yes certainly not 'D' (although you'd be amazed at how many people do!) - No job is worth risking your life like that for - also it's working live and is against the Electricity at Work Regulations (although, admittedly, EAWR does not apply to domestic works... hence Part-P)!

The supplier would have to find conclusive PROOF that it was YOU who pulled the seal (catch you on camera!?) to ever take action...

 

[ukants]

Pompey and Adam - thanks for your advice it really does help. I'm going to speak to the LABC again on Mon to see what I can and cannot do and I'll let you know the outcome. When I spoke to United Utilities (service provider) last week they told me they only deal with full disconnections and for a fuse pull for alterations I'll have to contact Npower - my meter/billing people, which I didn't realise. I thought one dealt with the 'hardware' and one with the 'software' . You learn something everyday.

Regards,
Ukants

 

[ukants]

Well...I'm still having probs sorting when npower can come and who's allowed to do what etc etc...but in the mean time a couple of questions:

It seems that the tails from service fuse (60A) to metre is 25mm (if you can see the image that's grey insulated cable) but 16mm (black cable) from metre to CU: http://img122.imageshack.us/img122/1614/pict00513jh.jpg

Certainly the grey cable feels thicker than the black one but is there a definate way of telling. If this does turn out to be the case, is it ok? I'd have thought all tails should be the same size. When an isolator is added between metre and CU, should the new tails between isolator and CU be 25mm even if it turns out one or both of the others are 16mm?

Also, could one of these 63A CUs be used as an isolator http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=A331831&ts=79807&id=61591#

or am I better off with a 100A DP switch in a suitable enclosure?
(I note that 60A DP switches are hard to find or even more expensive than their 100A counterparts ( http://www.tlc-direct.co.uk/Main_Index/Consumer_Units_Index/Mk_Sentry_Mcb_and_Accessories/index.html ), so I presume a 100A will be as good as, if not better, for isolation, even thought he service fuse is only 60A.)

Cheers,
Ukants

 

[Adam_151]

No problem with using a 100A isolator, its would be a good idea to do so, incase the service fuse is ever upgraded: recommend you use one of those: http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=A331832&ts=85705&id=53010 in one of these: http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=A331831&ts=85737&id=74436

16mm tails are ok for 60A, but use 25mm for any new stuff incase the service fuse is ever upgraded, so there are less tails to replace (the exception might be from a henley block to a shower CU where you know the load is never going to be more than 50A for example)

I think Npower is the wrong company, think they are just the people who take money off you, not the people who fix things

 

[ukants]

Thanks for that, Adam. Think that that isolator and 25mm tales are the way to go (when it eventually happens! )

I think Npower is the wrong company, think they are just the people who take money off you, not the people who fix things

I agree - this was my original thought (see my reply above) - but United Utilities and Npower can't seem to make their mind up!