can i do this?

[matt456]

i am going to put a spur from a ring main for my niceic inspection, the installation is proteted by 1 rcd over 2 cu's is this ok? im not wiring a new circuit just taking a spur off of the ring. Does the ruling of the 17th where you should have 2 rcds in place come in to play? the installation is around 15 years old.

 

[Mark.W]

As long as the ring is protected by an RCD then I see no problem. Which cu is the ring in?

 

[matt456]

The second cu is for storage heaterpoints which are used currently as radial sockets and connected to on peak electric, the system was designed to the 16th so is itjust a recommendation I would make?

 

[Mark.W]

Yes, any socket outlet up to 20A should be protected by an RCD, so I would put it on the cert, and recommend one be put in!

 

[matt456]

As long as the ring is protected by an RCD then I see no problem. Which cu is the ring in?

The rcd feeds a Henley block which then feeds both boards, as long as there is 30 ma protection I am ok to do the spur? The fact the whole install is covered by one rcd not 2 is ok as it was installed years ago? I will recommend on the minor works that it could be split up and have 2 30mas fitted?

 

[Mark.W]

As far as I was aware, the RCD had to directly protect the sockets. It sounds like they are currently protected by a main switch, and the whole installation is protected by an RCD. Not sure on this one.
Someone will be along in a bit to give some better advice.

 

[matt456]

Sockets are protected I think as trip times are fine when checked with rcd tester

 

[zupos40]

Sockets are protected I think as trip times are fine when checked with rcd tester

I would say that this installation do not complies with BS7671:2008 Reg 314.1(iv), that why we have more then 1 rcd in CCU now.

 

[matt456]

What's the alternative then? It could be a pricey skt the way things are going and I need it doing for my niceic inspection, some of the rules they make are getting silly. Should I fit a second rcd in front of the other cu?

 

[zupos40]

What's the alternative then? It could be a pricey skt the way things are going and I need it doing for my niceic inspection, some of the rules they make are getting silly. Should I fit a second rcd in front of the other cu?

I hard to give a difinite answer, but have you considered place the ring you are adding on Rcbo or removing the ring from the CCU and place in a seperate RCD module and supplying it in 6mm from the 32A cb. in the CCU.

 

[matt456]

is that the only way? i might do a light under the stairs instead as this could be easier than a socket. If i priced that extra socket for a customer then that would be in excess of £150.00!
no wonder cowboys are still in existence.
anybody else have any ideas

 

[Gravid]

Hey up Matt, that reg that Zupo says was what i was trying to find last night. Sounds to me like it needs upgrading, I'm not sure but i think the division of ccts came in with the 16th.

Its not just for the socket though is it you'll making their installation comply with todays regs, and making it good for 10 yrs +.

What about bonding to is that in place?

 

[matt456]

I hard to give a difinite answer, but have you considered place the ring you are adding on Rcbo or removing the ring from the CCU and place in a seperate RCD module and supplying it in 6mm from the 32A cb. in the CCU.

surely this would then make it 2 rcds inline so if the circuit tripped out it would take the other with it? Not sure if i explained myself clearly. im not adding a new ring or anything just spurring one socket as a minor works for my inspection. This seems a very costly way of adding an additional socket?

 

[chocolate]

It's not ideal having 1 RCD module protecting the whole installation. But as you say, that was there already. You are adding to an existing circuit ( assuming all main bonding, etc ) is sorted.
What sort of circuit breakers / fuses are in use ? If normal MCBs or rewireable fuses, then acceptable as they comply. If the POP-OUT type, then you shouldn't add to that circuit - they no longer comply.
Check it is a ring. Add your spur and whatever you're adding. Do the testing bits and bobs, making sure the numbers you get are acceptable. Then as long as you are happy.
Ideally, you'd redo the lot to the way you thought it should be. But that would cost loads of money, and the customer would probably shut the door behind you.

 

[matt456]

thats what i was thinking, it has to work for both parties as long as there is rcd protetion and main earthing then it should be ok. i will see what the inspector says!!