Consumer Unit RCD & split load

[AndyPRK]

I notice these were being sold off (split load). I assume this is because they are 16th edition ?

The only difference I can see with the 17th edition is the 2nd RCD. Is it now a requirement to have both RCD's for a split load ?

Can someone please give me some tips on how to configure the split load and what the reasoning is ?

Is it to cut one half off when you go on holiday ?
Is it so that half your house works when the RCD goes ?


I was going to put the alarm, fridge,boiler and 1 light circuit on the right red part.

I guess I should buy a 2nd RCD to go in it ? I notice in another thread it states that all sockets should be covered by a 30mA RCD.

Thanks for any tips


Note to self. Must read this:
http://www.electrium.co.uk/Wylex17th Edition.pdf

 

[Steve]

Its not a requirement to have all circuits RCD protected. BUT it is one way of meeting other regs. One such reg is that all un-armoured concealed cables buried less that 5cm must be RCD'd. Another is that all circuits in a bathroom must be RCD'd. Its hard not to RCD a circuit with all this flying about.

It is possible though. You could run cables through trunking, use SWA or MICC, bury cables 5cm deep (not possible most of the time).

You will struggle to build a 17th compliant board starting with a split load.

 

[AndyPRK]

I notice there are different rating leakage current RCD's available for this unit

30mA and 100mA

In what case would you use a 100mA ?

 

[ezekiel]

often on tt system to meet 30ma rcd requirements and all other circ under 100ma ?

 

[EdwardCurrent]

Sorry a bit slow here

Hello Andy,

All cables buried less than 50mm must be mechanically protected, within safe 'zones', and the 'protection' (conduit etc) must be earthed, otherwise, they need to be RCD protected.
Socket outlets for your fridge/freezer, smoke alarms etc do not need to be RCD protected, but must be mechanically protected as above.

The use of separate RCD's will enable you to divide the installation in such a way that in the event of a fault say on the shower circuit, that your bathroom lights don't trip at the same time etc.

I personally would look into RCBO's.

Hope this is of some help.

Ed

 

[AndyPRK]

I have an old system, with the earth spike in the ground

 

[Cremeegg]

You will struggle to build a 17th compliant board starting with a split load.

Rubbish - no such thing as a 17th edition board anyway.

Why not a "16th" split loader then fill the non RCD side with RCBO's - far more complaint than the so called 17th edition boards with 2 RCD's. Best way to use RCBO's all over.

 

[EdwardCurrent]

Hello Andy,

It sounds very much like a -TT- type service.
The changing of your C/U is notifiable, and the changing of it will involve testing and inspection, carried out by a 'registered' electrician. You are not thinking of changing the C/U yourself as a DIY project are you ??

Ed

 

[AndyPRK]

What's an RCBO anyway. A circuit breaker and trip built in one ?


I guess I could fit one or two on the non RCD side for good measure. lol.

Anyway do I buy a 30mA or 100mA RCD ?

 

[AndyPRK]

Hello Andy,
You are not thinking of changing the C/U yourself as a DIY project are you ??
Ed

No, no of course not.

 

[Cremeegg]

If you have to ask these questions you a) shouldn't be even thinking about doing the work b) need to get a registered electrician in and c) haven't read many posts on this site or d) used the search function.

 

[EdwardCurrent]

(Cremeegg)
I agree, and have read about 'PCA's' , (a partially compliant assembly). which is a dual RCD and isolator unit. Not fully compliant because of the disconnection of the other MCB's governed by the RCD.
It would appear that RCBO's are the way to go.
JohnD knew it all along .

Ed

 

[flameport]

I have an old system, with the earth spike in the ground

In that case, ALL of the circuits must have RCD protection. That board will only be of use if another RCD is fitted.

 

[JohnD]

hooray for RCBOs

 

[AndyPRK]

I have an old system, with the earth spike in the ground

In that case, ALL of the circuits must have RCD protection. That board will only be of use if another RCD is fitted.

There is already a trip before the CU though ?