Ring Main Regulations

[taycast]

My house is about 6 years old. I have always suspected, but now just confirmed that my entire ring main (downstairs, upstairs, and the garage) are wired into one MCB. This MCB is protected by an RCD (?) There is another MCB marked "sockets" in the distribution board but I have switched this off and every socket in the house still works

Does it matter that all the sockets are wired under one breaker? Are there not rules which say that the ring should cover a max of 100m2 of floor, and that the cable run should be no greater than 50m ( both of which my house exceeds)? Thanks in advance of your thoughts

 

[breezer]

50m cable run is not right.

 

[taycast]

Do you mean you can have a ring main longer than 50m?

 

[breezer]

in theory you could cover a room on all 6 surfaces with sockets and so long as it was no bigger than 100m floor space its ok.

probably cost a fortune in sockets though

(oh just thought, how would you get in the room?)

 

[fireman22]

have you taken cover off fuseboard to see if there are cables going into other breaker?
what is the rating of the other breaker?
if you switch off your house breaker do your house sockets actually go off?
the rings may be interconnected in the fuseboard

 

[fireman22]

as the house is six years old i am sure it would not have been wired with only one ring............maybe

 

[taycast]

Thanks - if I switch off one breaker the whole house sockets go off. If I switch off the other one, nothing happens. If I switch off the RCD the whole house sockets go off. Both the MCBs are green, although I dont know what rating.

I haven't removed the cover as I am not sure how safe it is to do this. If I switch off the main switch in the board ( covering lights, sockets, cooker. immersion and smokies) is the board safe to take a look? Alternatively, the digital meter from the supplier has a white screw switch saying turn to switch off. Can I turn that to make the board safe to look at? Its a Tenby board with red mcbs for the lights, smokies, cooker, Immersion, and green for the sockets.

 

[fireman22]

if you have a main switch you can turn off that to isolated whole board, obviously you will need a torch. if there are no cables in the 2nd breaker but say four in the house breaker it may have a faulty breaker and both ring circuits have been put in one breaker so all sockets work, and someone has forgotten to get and change the faulty breaker, again maybe.
have a look

 

[fireman22]

as you say you have two green breakers i guess these are 32A, it should be written on them somewhere, it should have been wired for two rings

 

[fireman22]

if your house is six years old you should be able to get it sorted under the building scheme

 

[taycast]

Thanks fireman. Wee one's in bed now so will take a look tomorrow and see whats what behind the cover. Will let you know. Appreciate your thoughts etc.

 

[fireman22]

my pleasure, hope it helps

 

[securespark]

GREEN????

45A???????

 

[taycast]

Hmmm - I think I need to call in the professionals as I removed the cover and the breaker that I have switched off has three lives coming out of it. The breaker which covers all the sockets in the house has 2 lives coming out of it. Have no clue where the three lives are going. Maybe my house has rooms I dont know about!

 

[fireman22]

are you 100% sure when you turn off only one breaker you loose all sockets in the house? it sounds like an interconnection to me.