RCBO instead of switchfuse for submain?

[Johnny-G]

I haven't seen this job yet (going in morning) but apparently the customer's builder has found that the majority of cables for upstairs circuits have been pulled through past a metal joist and it's skinned a few of them, their re-wire about 10yrs ago was a complete shocker so I'm not surprised.
The builder reckons it will be easy enough to stick a new CU upstairs with the affected cables in and run a new main to it (about 6m), splitting the tails in to a henley.
Can I use an RCBO (prob 40a)after the henley and just a main switch & MCBs instead of a switchfuse if the new tails require RCD proctection

 

[imago]

That seems like a lot of work to repair damaged cables? Is there another reason for moving/adding a CU?

 

[Johnny-G]

I don't know, I'm assuming that they're in the way of the work the builder is doing so they've got be moved anyway and it might be easier just pulling them back up than replacing the whole runs.

 

[Guest55]

Perfectly fine to use rcbo for submains
overload , isolation and rcd in one 20mm wide module

 

[Johnny-G]

Ta.
I'll have a chat with EDF first but just wondered if anyone knew of any obvious reasons why I couldn't.

 

[Guitarist]

DP RCBO in enclosure I assume?

 

[Johnny-G]

Of course, basically a switchfuse in all but name plus glorious RCD protection.

 

[Guitarist]

Of course, basically a switchfuse in all but name plus glorious RCD protection.

Sounds good mate.

 

[sjm]

Buy a Wylex REC2 main switch. Throw away the main switch and fit your RCBO in it's place, a Wylex RCBO would be perfect for fit. Your tails will fit perfectly into the Wylex unit as they are designed as a DNO isolator to take tails.

 

[rich.250]

Sounds like a plan but does the sub even need Rcd protection??