DIY Doctor UK DIY Forums

Getting an electric shower 10.8kw.
Got 10mm t+e cable and route from shower room is easy up to the loft and across. But down to the supply is not. Will have to go through another bathroom. I intend to run cable vertically down wall about 2" away from another perpendicular wall. Wall is outside wall with plasterboard. As it is within 150mm is it ok to just cap the cable and fill with plaster?
Next problem is that although the house is only 20 yr old it has memera fuse box. How can an mcb be connected into this?
I just want to do the donkey work and let an electrician check and make the connections. I dont want to connect the mcb myself just want to know what preparations might be needed.
Any advice welcomed.

Hi nonplumber,
Although you are proposing to run in so called 'safe zone' in corner the circuit must have RCD protection at source.
There is, I feel, only one way you can do this with your old memera fuse board which is for your leckie to fit an add on 'shower unit' sold for the purpose.
These have RCD & MCB protection in a box which is prewired and just needs tails & earth connections via a set of 'Henley blocks' and the outgoing 10mm2 tw/e connecting in.
No doubt your registered 'part-p' leckie will know this, don't forget local 50A isolator switch for shower end also, and as other circuits in shower room ie lights are probably not on RCD the pipework still needs supplementary cross bonding,
best make contact with leckie first and agree on what you can do to save time/money, at the end of the day he will have to sign off the job as if he had done it all himself,
regards SPARX

Thanks Sparx.
That makes me feel better as I had already done the things you mentioned ie bought the RCD/MCB shower unit. Its still going to be a bit tricky connecting it to the fuse box but thats why leccy will do it!
[b]NEW question:-[/b]
How close can a 15mm copper feed to shower, coming down from the loft, be to the supply cable from the switch, again coming down vertically from the loft?

If the cable is isolated by some insulation material eg minitrunking then can be next to each other,