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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Electrical Questions >> elec shower https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1094752656 Message started by spot on Sep 9^th, 2004, 6:57pm

Title: elec shower
Post by spot on Sep 9^th, 2004, 6:57pm

???
heres one for you lot,
i have a 9.5kw shower and at the moment it has a 2.5m
cable going to the pull switch! then from there a 10m cable going to the c.u.
I know i will have to replace the 2.5m cable for 10m.
But here is the question.... the c.u has no RCD fitted so the shower is not protected. can i fit an in line RCD to the shower circuit??? rather than change the whole C.U ?

Title: Re: elec shower
Post by Beanzy on Sep 9^th, 2004, 8:23pm

Yep. Can buy them complete with MCB from TLC, or Screwfix, but may get better price from your wholesalers. Don't forget to sort out the earth bonding too. If unsure re this post a follow-up one on here and will update you.

Title: Re: elec shower
Post by The_Trician on Sep 9^th, 2004, 10:38pm

Don't know what make or age your CU is; but you might be able to get something which will fit straight into it.

More info needed though.

TT

Title: Re: elec shower
Post by L.Spark on Sep 10^th, 2004, 12:04am

Yep, cable will need to be changed, if it's a modern board you can get a RCBO, which is a combined RCD and a MCB (fuse), if it's an older board, the alternative is to fit a seperate box with a RCD in next to the board, and run the shower through this, the RCBO or RCD would been to be 45A.

Title: Re: elec shower
Post by Lectrician on Sep 10^th, 2004, 1:16pm

Of course, there is actually no requirement to provide an RCD for a shower circuit, as long as the disconnection time of 0.4 seconds can be achieved with a fuse or MCB, which in a domestic environment with 10mm shower cable should be fine. I would be extremely surprised if the Zs would be exceeded.

But then, for a few quid for an RCD, it would make you feel a little safer - mine has an RCD ;)

Yep, upgrade your supp bonding as well.

Title: Re: elec shower
Post by ChubbyPhaseWire on Sep 10^th, 2004, 2:14pm

Protection against electric shock
Bathrooms and shower rooms
Disconnection times for circuits supplying current-using equipment are no longer reduced to 0.4 s. However, 30 mA RCDs are to be fitted to the circuits of certain items of current-using equipment (see Table 1B)GN7.

Title: Re: elec shower
Post by spot on Sep 10^th, 2004, 6:53pm

Cheers for the info guys........
yes the C.U is an old type and cant hold an rcbo which would have been a top job! if i put in a new shower C.U would i have to run tails to the mains terminal block or could i get the supply from the original CU? ???

can you run-through the earth �bonding for the shower!
many thanks
spot......................................... ;)

Title: Re: elec shower
Post by plugwash on Sep 10^th, 2004, 7:47pm

what kind of CU is it there presently

remember the wylex standard CUs with isolators below 100A are not meant to take any protective device over 30A

and good f**king luck getting proetctive devices for any other brand of that age

Title: Re: elec shower
Post by Beanzy on Sep 11^th, 2004, 12:40am

Yes you'd have to sort the meter tails out. Which means you'll have to remove the main fuse and take full precautions. I'd hold fire on any of this one unless you have the necessary test kit. It's safer and probably much quicker to get a pro on this one, not really the realms of DIY. If it were a modern CU which just required the relevant MCB and you had access to test kit, or someone who knew how to drive it, then you could possibly do it. There's too much scope for error with this one as it is.

On the earth bonding issue this can help explain much;

http://www.niceic.org.uk/downloads/NL139supp.pdf

Also get hold of the IEE on site guide if you do or intend to do any DIY electrical work, it's a good base to get proper info before deciding which jobs you may want to do yourself, and which may be a can of worms for you.

Title: Re: elec shower
Post by L.Spark on Sep 11^th, 2004, 1:39am

wrote on Sep 10^th, 2004, 7:47pm:

lol, calm down ::)