Using RCBO as RCD

[Jim K..]

I read it as the nice one is not currently (or going to be) installed at that locale...

[spuorgelgoog]

Running out of space in the consumer unit, and the split-load kits only allow 2 x RCDs.

It occurred to me I could use an RCBO in one of the 'high integrity' ways next to the main switch, and link the load terminal of that to a group of 3 MCBs on their own bit of busbar, instead of using another RCD. RCD and RCBO are about the same price, and I save a module as the RCBO is single width.

I'd have to conjure up another section of neutral bar too.

Any reason why not? CU is BG, and I'd like to keep 3 x 20A heater circuits off the normal RCD and on their own separate section so it's easier to put them on a contactor or timer later if desired. Total load is 9.3 kW before diversity.

I have decided that enlarging the front panel opening to take another couple of ways would be gash, especially as it's flanged. (It would work with the latest flat-fronted metal Fortress design though.)

Owain

[tabbypurr]

Maybe you could add slots for 2 more RCBOs on the sides :)

NT

[spuorgelgoog]

A length of DIN rail screwed to the meter board ...

Owain

[tabbypurr]

Making your own fusebox was once common practice.

[stephenten]

Why not rip out both RCDs and all the MCBs and replace with RCBOs? The space taken up by two RCDs will give you space for 4 RCBOs which is four extra circuits on top of all your previously MCBed but now RCBOed circuits?

Just link up the two neutral bars and link up the two live bus bars....

[ARW]

Why not just fit 3 RCBOs?

[stephenten]

Perhaps he was after a triple split load wth three RCDs, three neutral bars and three live bars?

I.e move three MCBs onto its own 3rd RCD but has only spare space for a single width unit like a RCBO but not a double width unit like a RCD.

But yes you do make a good point as the three existing MCBs could be replaced with RCBOs and wired into the incoming live and incoming neutral.

[spuorgelgoog]

Cost. This is a cheap/temporary job, hopefully before I can sell up and move.

(I am taking that nice new BG Fortress 22-way CU with me, not leaving that behind.)

Owain

[spuorgelgoog]

My joinery really isn't good enough, and I don't have any asbestos lying about.

Owain

[dennis]

That's OK just use steel.

[Robin]

I've heard of people moving in to find the previous owner took the light switches and sockets but never the CU. OTOH so long as you don't lie when answering the questions to sellers ISTM there's just Part P. I don't know if you might face issues there: the legislation referred to the provision or replacement of a consumer unit and I don't know if that covers replacement with SFA :)

[tabbypurr]

Well there's always the 1890s forerunner - a piece of slate on a wood frame, with holes poked through it where wood screws go in to hold the bare fuse wires. No lid. I don't really recommend it though. The total cost of 1 used slate might appeal.

In the 1890s installing that would have been considered impressive. Today it would be considered reason for a custodial sentence.

NT

[ARW]

Then just move the RCDs along a bit to the right and use the free spaces you have created for the MCBs.

[spuorgelgoog]

Is correct. It was going to be, but I'm not leaving forty quid's worth of new steel CU when there's a manky plastic one can be made to look good enough to pass a surveyor.

I might take the Wylex isolator too, that was eighteen quid from Ebay. £38+ VAT from TLC!

Owain

[spuorgelgoog]

That was the original intention, but triple split load kits appear unobtainable from any manufacturer.

Owain