Ring main not originating in the DB.

[andygosmore]

It's obviously not good practice, but is there a specific reg prohibiting a 4mm from the board to a remote rcd a few metres away, & then a 2.5mm ring from the rcd, round the sockets then back to the rcd. I've come across it on a PIR, and unsure whether to pull it up or not.
Thanks
Andy

 

[ackbarthestar]

None as far as I can see. It doesn't feature as a conventional circuit in the OSG, but then if you do the sums and check the installation method and any other correct factors, it should be Ok.

I believe they call that type of circuit a 'loolipop'

A note on the PIR/EICR stating there are loolipops in the house should do it !

 

[jase]

in effect the 4mm is just acting as a submain to the RCD and then a ring main off of it, this would be no different than an SWA going down to a remote RCD board in the shed and a ring main coming of of that,
as long as the calcs work out

 

[Engineer54]

For futher reading on this subject, check out ''SIMILAR THREADS'' at the bottom of this page!!

 

[Dannyspark]

It's obviously not good practice, but is there a specific reg prohibiting a 4mm from the board to a remote rcd a few metres away, & then a 2.5mm ring from the rcd, round the sockets then back to the rcd. I've come across it on a PIR, and unsure whether to pull it up or not.
Thanks
Andy

I can't remember the exact reg number, but I'm sure their is a requirement to fuse down at any point where their is a reduction in csa. From your description it sounds as though you only have an RCD locally protecting and not a fuse/mcb?

 

[GT1]

2 x 2.5mm isnt a reduction in CSA from 4mm though..
It's an increase in CSA.

 

[ackbarthestar]

2 x 2.5mm isnt a reduction in CSA from 4mm though..
It's an increase in CSA.

Because its ac it make sense that it would be oversized on the first half cycle and undersized on the second ?:dizzy2:

 

[ezzzekiel]

LOOLIPOP - i love it