minimun/max fuse rating for 10.5 elec shower

50 amp mcb all day long. Is this shower backed up by an RCD by any chance? And I hope you notified building control or got BC consent before you started. If not you risk being fined up to £5000.

Not only will you require a 50 amp circuit breaker, RCD protection is also required for ALL circuits supplying electrical equipment and accessories that are located in a room containing a bath or shower. You will also need to ensure that main bonding conductors are present at your water and gas inlet pipes if they are of metallic construction, and that the bonding conductors, if present, are adequately sized. Finally, all the electrical work you have done will need to be certified, and if you live in England or Wales, you should carefully consider what Deacon Electrical Services have advised.

Hi, A 40 amp fuse would not be adequate. It would need to be 50 Amp. Without seeing the installation you could not be advised because of a number of factors which would affect the cable sizing of the installation.

Hi There, you would need a 50 amp fuse, as doing a few basic calculations 10.5kw divided by 230 equals 45.6 amps. Also taking into consideration the installation method and length of cable run this could also change things. Hope this helped Mike

It should be a 50 amp circuit, however as most appliances are not required to work at full demand it is possible that if the 40 amp was fitted you may 'get away with it'. I have come across installations such as you speak of with the owners using the shower and experiencing no issues or as one client of mine said it only trips occasionally usually when there is no one in the house to reset it!!