MCB`s and my shower

[motofox]

Hi, my electric shower is an 10.5 kw. iv installed 10mm cable and ahve bought a new consumer box complete with 10 mcb`s and a rcd already installed. iv had to buy another mcb to put in tho rated at 50amp. with this be okay for a 10.5kw shower

 

[luminaire]

It would need to be 50A.
Hope your RCD is big enough to take the load.
Also I presume you know this work is notifiable to your LABC.

 

[Jim2287]

shower switch needs to be 50 amp also

 

[Albert]

the MCB value depends on the load but more important is the capacity of the 10mmsq cable. The capacity of the cable depends on the method it was installed, for example: if it was clipped to the wall or other part of the building (method 1), and no external or thermal influences it can carry 63A, if it was passed via isolation and other influences it will be reduced to under 43A (method 4).

Remember that the MCB purpose is to protect the cable, and always should be less that the cable capacity. You are the one who put in the cable you are the one to decide whether it is ok or not.

The RCD will protect against indirect contact earth fault, the MCB will protect against overloading and a electric short (this is only simple explanation)

I hope that the above information will help you with your discission.

 

[motofox]

Thanks for that, the RCD is rated at 80amp 30ma . One last question, is there a problem with the 10mm feed cable touching the plastic polypipe water feed pipe to the shower, well it would actually pass under it . thanks in advance..

 

[Albert]

should not be a problem if the pipe is cold water, if it carries hot water I would try to protect the cable.