question about 9.5kw electric shower installation

[shintrobo]

Hello!
I want to install 9.5kw electric shower in my bathroom. I have wylex MCB with 80A 30ma RCD (2x32A for ring socket and 6A central heating are already connected through RCD)

Do I need 50A nsb50-b or is it O.K. with 40A?

What do I need to get if I conect through RCD? or can I connect without RCD?

 

[electronicsuk]

Sorry to break it to you, but from your post it's clear that what you need to do is step back and realise that you don't have even the first clue about how to carry out this work. It's also notifiable under part P of the building regs, you can carry out the work legally if you notify the LABC first and pay their fee, but from your lack of knowledge it seems unlikely that your work will pass their inspections.

You need to go away and decide whether it will be cost effective for you to do this work once you've paid the LABC fees. If you decide in favour, have a read up on basic electrics in the WIKI before you come back. Otherwise, take the sensible action and call a spark.

 

[Softus]

I want to install 9.5kw electric shower...
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Do I need 50A nsb50-b or is it O.K. with 40A?

If you're referring to the rating of the breaker, it needs to be enough for the maximum current that the shower will draw, which will be 40A. You will need to select the correct type of breaker for the circuit. You will need to gain the knowledge required to carry out that selection.

What do I need to get if I conect through RCD?

You will need to use cable that will carry this current safely. The size of conductor depends on the distance from the CU and the route that the cable takes, because cable length affects voltage drop, and insulation and other environmental factors affect its current carrying capacity. You will need to gain the knowledge required to select the right cable conductor size.

or can I connect without RCD?

No, you should not connect it to the non-RCD side.