Electric shower cable thickness

[ban-all-sheds]

I'm not mocking anyone... just thought someone would be able to give advice which even if it covers the worst case scenario eg, if I want the most powerful shower over 50 metres, what would the spark do when installing?

He'd work it out.

Just like you can, if you are neither too thick or too lazy.

• //www.diynot.com/wiki/electrics:mcbtocable
  
  
• http://www.tlc-direct.co.uk/Book/4.3.1.htm
  
  
• http://web.archive.org/web/20080213151445/http://www.kevinboone.com/cableselection_web.pdf
  
  
• http://www.tlc-direct.co.uk/Book/4.3.11.htm
  
  
• http://www.tlc-direct.co.uk/Book/5.3.1.htm
  
  
• http://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html
  
  
• http://www.tlc-direct.co.uk/Book/8.1.1.htm
  
  
• //www.diynot.com/wiki/electrics:part-p

He'd know pretty much what size of cable to put in right?

So will you know, when you've worked it out.

So that's what I'll put in - it's 10mm at the mo, the old shower worked perfectly for the 7 yrs we've been there and it was a B&B b4 that which ran for 6 yrs so if there was a problem, I'm sure it'd have happened by now?

I haven't had a car crash in the last 13 years. I'm about to leave and drive up a motorway. Shall I not wear my seatbelt?

no need for taking out 3 weeks to read 96,000 pages of gumpf in a bid to try and become a qualified electrician!

No need at all - just get someone who is.

Simples.

F*ck me, it ain't rocket science!!

Well that's ruled out the possibility of it being beyond you.

Which just leaves the fact that you can't be bothered to do it properly.

Get an electrician.

 

[OilLecky]

I've not checked this site for some time but am horrified to find this thread.

Mr Split: As you have been advised, this job is not a DIY task. There are many factors that determine cable size for a set load, not just the load itself.
This is not the kind of thing that you can take on with "a knowledge of physics". You need to have access to and understand the workings of BS 7671:2008 and you need to notify building control if you intend carrying out an installation of a shower yourself so that they can inspect it. They will most probaly want to see your calculations for the cable size which you probably cannot provide.

Safe yourself some trouble and get a qualified electrician in.

 

[Deansplit]

Well guys I appreciate all the advice, but as you know I thought there'd be a quick safe answer, or as mentioned an good safe 'over compensation' type suggestion. My electrician friend was away on holiday when I started this thread but is now back. I explain my requirement, mentioned what I was told here, even posted a few answers and this is his reply:

"10mm is plenty big enough. Shower should also be protected by a 30 milliamp RCD as well as a fuse/circuit breaker"

This is exactly what I was looking for - I can take it from here, as I did when I installed my sauna. But why couldn't have anyone here given this type of answer?

 

[1john]

Because it may or may not be correct under certain circumstances.

 

[riveralt]

Well guys I appreciate all the advice, but as you know I thought there'd be a quick safe answer, or as mentioned an good safe 'over compensation' type suggestion. My electrician friend was away on holiday when I started this thread but is now back. I explain my requirement, mentioned what I was told here, even posted a few answers and this is his reply:

"10mm is plenty big enough. Shower should also be protected by a 30 milliamp RCD as well as a fuse/circuit breaker"

This is exactly what I was looking for - I can take it from here, as I did when I installed my sauna. But why couldn't have anyone here given this type of answer?

Did he also advise to inform your Building Control. How to calculate the R1 and R2 numbers and what you should expect; Insulation resistance values required; how to test for Ze and Zs. How about the Prospective Earth Fault current and Prospective Short circuit current measurements - and since your are going to use an RCD how to measure the trip times.

What do Building Control feel about your capabilities to fit this shower?

But then given the poor level of knowledge you have demonstrated in these pages and your obvious inability to follow simple instructions, as outlined by BAS, you probably will fail to inform Building Control.

After all an englishman's home is his castle - until it burns down...

 

[securespark]

But why couldn't have anyone here given this type of answer?

Because it's just far too generalised.

I thought there'd be a quick safe answer

You know what's coming, don't you?

Over to BAS....

Like I said before, if you want sound advice from qualified sparks, you need to provide far more information than you have volunteered so far.

You do seem hell-bent on getting this shower up and running regardless, so good luck to you.

 

[ban-all-sheds]

There is a quick, safe answer: Get an electrician.

There is a less quick, but just as safe an answer: Learn to do it yourself. And that means LEARN to DO it YOURSELF, not ask other people to tell you "insert wire A into hole B" without you having a clue what's going on.

• //www.diynot.com/wiki/electrics:mcbtocable
  
  
• http://www.tlc-direct.co.uk/Book/4.3.1.htm
  
  
• http://web.archive.org/web/20080213151445/http://www.kevinboone.com/cableselection_web.pdf
  
  
• http://www.tlc-direct.co.uk/Book/4.3.11.htm
  
  
• http://www.tlc-direct.co.uk/Book/5.3.1.htm
  
  
• http://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html
  
  
• http://www.tlc-direct.co.uk/Book/8.1.1.htm
  
  
• //www.diynot.com/wiki/electrics:part-p

 

[OilLecky]

So he's got a sauna and a shower as a DIY installation.
I wonder what insurance company would not invalidate the policy for any subsequent claim?