just finished installing two extra 240v sockets. i opened the consumer unit to find a single 10a MCB radial circuit to feed all sockets,heating and aircon unit and possibly the fridge and a single 6a MCB for the water boiler and possibly the fridge. (forgot to check which circuit for the fridge.) the RCD main switch is 40a. when we rewire houses we use a 32a MCB/RCD for socket ring circuits and 16a for radial circuits. the aircon unit alone uses 7amps which doesnt leave a lot for other stuff. do any of you techies know a reason for the 10a MCB as opposed to a 16a and is this the norm ? all cables are 2.5mmsq 3core flex(L+N+Earth) and relatively short in length so quite capable of carrying 16amp. is it to do with splitting the load for the 16a hookup post? 10a + 6a MCBs thats the only thing i can think of. suppose one advantage of the 10a is, i wont trip the 16a site supply 'cos it'll trip in the van first.