Running ring through RCd

[emphasis303]

Hi guys

Im going to connect to a 32mcb in the consumer unit and wanted to know if it were possible to run a ring through an rcd? So in effect I would have two cables going in and two going out.

The Rcd will be protecting an outbuilding.

Cheers

 

[RF Lighting]

Can't you just put an RCBO in the CU?

 

[emphasis303]

I was initially thinking that but the cu can sometimes be a job on its own to get through all the junk in the garage, so i was going to have an rcd right by the door for ease of access.

 

[RF Lighting]

How often are you expecting to have a fault severe enough to trip the RCD?

Mine has tripped twice in 10 years. Once as the element on the steam iron failed, and once as my father hedge cuttered the lead off the hedge cutter.

 

[emphasis303]

lol ur probably right

rcbo it is

cheers rf

 

[sparkwright]

what make is your CU? and approximately how old is it?

 

[emphasis303]

its a wylex it was installed with a complete rewire in 1994 so its getting on but its brilliant, all wiring is like new, the only thing its lacking is any rcd protection but ive been thinking of changing it in the next few years.

 

[sparkwright]

i may be wrong, so further investigation may be needed, but your cu may be from the old nn range which i don't think accepts the current range of wylex rcbo.

you can easily check this by having a quick look at the wylex rcbos in b and q; about the only place open today that sells them.

if your cu is obsolete you have two options;

1) isolate all power and remove your ring cables from the desired circuit. run one 6 mm twin and earth from cu to a 2 module stand alone enclosure containing an rccb. connect the original ring cables to the output side of this rccb. join all earth wires up.

make sure the rccb is rated above 32 a. it should be noted that this rating is not is not be confused with the overcurrent protection of a mcb or an rcbo.

2) the best and most cost effective method would be to replace the entire cu with a 17th edition dual rcd cu. this will give you the added safety of all your circuits being rcd protected. all sockets should be protected. all concealed wiring less than 50 mm deep would be protected.

are you planning on doing this yourself?