Circuits for white goods

[DJ12345]

Hello everybody! I just wanted to ask, what would be the best practise to run circuits for white goods?
In my plan what i see is:
1. Fridge & Freezer 20 amp RCBO radial wired with 2.5mm
2.Washing machine 20 amp MCB Radial 2.5mm
3. dish washer 20 amp mcb radial with 2.5mm
4. Washing machine and dish washer 32 amp mcb wired 2.5mm ring final.

Please advice what is the best practise to do it? would it be too much having dish washer and washing machine on separate circuits or just wire them both on ring final?

Also advice me please with mcb sizes if i am correct about radials. As far as i rememmber from regs maximum mcb rating for radial is 16amp.

Thank you

 

[DPG]

Why RCBO for the fridge and MCBs for the rest?

 

[DJ12345]

Why RCBO for the fridge and MCBs for the rest?

I have seen it before, worked in few houses like that, thats why i am asking whats is the best practise.

 

[DPG]

I have seen it before, worked in few houses like that, thats why i am asking whats is the best practise.

Surely you will need RCD protection?

 

[DJ12345]

Surely you will need RCD protection?

CU has 2 Rcd in it.

 

[DJ12345]

Consumer Unit has 2 RCD protected sections.

 

[nicebutdim]

Consumer Unit has 2 RCD protected sections.

RCBO for fridge freezer protected by RCD?

 

[DPG]

Consumer Unit has 2 RCD protected sections.

So why the RCBO for the fridge? Can you give use a bit more info, it feels like a bit of a drip feed.

 

[stevethesparks]

Is the CU a high integrity unit?

 

[brianmoooore]

If this is a domestic set up, a single 2.5mm2 radial fed by a 20A RCBO is adequate for all three, if the water heating elements in the dishwasher and washing machine are 2kW.
If either are 3kW, then a 4mm2 radial fed by a 32A RCBO will do, but the washmac. and dishwasher shouldn't both be plugged into the same double 13A s/socket.

 

[DJ12345]

If this is a domestic set up

Yes it is.

and dishwasher shouldn't both be plugged into the same double 13A s/socket.

Unswitched socket behind devices on the wall and fused switched spur on the wall above worktop.

 

[DJ12345]

So why the RCBO for the fridge?

If device fails it trip only one protected circuit, not all circuit will be off in RCD unit

 

[DJ12345]

RCBO for fridge freezer protected by RCD?

no

 

[telectrix]

RCBO for freezer, rest in a 32A RFC with 20A D/P switches above w/top feeding single sockets below. unless you want a load of grief fitting grid switches.

 

[DJ12345]

unless you want a load of grief fitting grid switches.

I just thought about grid switches. Just have 4 circuits(dish washer, washing machine, hood, freezer).