In article ,
John Rumm wrote:
On 22/06/2015 11:18, Mike Clarke wrote:
On 22/06/2015 11:05, John Rumm wrote:
For your installation with relatively few circuits, the "nicest"
solution would be an "all RCBO" installation. That is one where you use
RCBOs (Residual Current Circuit breaker with Overload protection) - i.e.
a combined MCB and RCD in one. That way you get the best of both worlds
RCD protection on every circuit, but also perfect discrimination - a RCD
trip will only deactivate the circuit with the fault and leave the rest
untouched.

The OP mentioned separate upstairs and downstairs light circuits. It's
possible that the landing light might have "borrowed" the neutral from
downstairs. If so this would need to be rectified before RCBO's could be
used for these two circuits.

Indeed - there are a few potential problems to crawl out of the
woodwork. Probably worth anyone thinking o doing their own CU swap,
having a read through of:

http://wiki.diyfaq.org.uk/index.php?..._consumer_unit


I did mine in the late 70s - shortly after we moved in here. The
Electricity Board man came at 8am - first call - to isolate. I suggested
that if he came back at 10am to reconnect, I'd be able to put the kettle on
when he'd finished. He arrived at 10- on the dot - and we had the kettle
going shortly afterwards.