Electric shower

Hi Dennis, if the 63amp circuit breaker also has 30ma marked on it then this is an RCD device and is generally providing earth fault protection to the circuit breakers placed after it. It is not normally a fuse in its own right. Where is the existing electric shower connected? What size cable has been run? A 9.5kw shower will need a 10mm twin and earth cable on a 45amp circuit breaker with RCD protection. If you're unsure please contact a local electrician as it's important this is done safely. Best of luck, Rob

Think by your question you need to call a registered (not just qualified ) electrician in as this is a notifiable job to building control, who will notify BC on your behalf. if you do this yourself you risk a fine of up to £5000, if BC find out. And you need a certificate also. Better safe than sorry.

Dependent on the cable sizing, length of run and any other effects such as thermal insulation the cable has to pass through/under, The OCPD (MCB) would usually be 45/50 amps when supplying a 9.5kW shower, Alongside a 10mm2 Cable. I would call a registered Electrician to get this work carried out so it can be done in the safest manner and up to the correct standards.

The best advice is to get a competent person to test and inspect the existing circuit to see if it is safe and suitable for the upgrade you have proposed. It's really as simple as that. No need to speculate on cable sizes at this point in time :)