Discuss Connecting/commoning RCBO Functional Earths. What do you do? in the Electrical Wiring, Theories and Regulations area at ElectriciansForums.net

Mark42

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What do you do with those untidy functional earth wires, especially if you have a lot of RCBOs in one board?

I suppose one is supposed to take each lead to the same terminal as the circuit’s CPC. But that can mean trying to reliably fit a skinny bit of stranded flex behind maybe a 6mm earth. Notwithstanding the perceived regulations/guidance, this is never satisfactory.

I’ve recently been using 1.5mm G/Y terminals on a short bit of DIN rail to take four or five commoned FE leads each, then commoning these terminals back to an earth bonding point with short bits of 2.5 G/Y solid.

The attached photo is part of a Hager board done this morning.

Adding a bit of curly wrap keeps things neat and prevents the board resembling the Flying Spaghetti Monster. The leads carry stuff-all current so bunching is irrelevant.

Is there any reason this might be unacceptable? I’m alone here in the wilds of Norfolk so do value second opinions! :)

Cheers, Mark
 

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shouldn't the 2.5mm common fly leads be cream to denote the fact, that they themselves are functional earths ;). and without being a jobsworth it looks very neat think I may also steal :D as for the fine strands on the fly leads I put bootlace crimps on the ends and this seem to give them enough strength to be terminated in the relevant circuit terminal, then I use the this stuff.

0000F676.jpg
 
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panel trunkingh is good stuff, but most CU's are hard enough to fit cables in neatly, panel trunking just compounds this.

Can use stickybacks with cable ties, just wipe the board dwn first, so they stick properly
 
panel trunkingh is good stuff, but most CU's are hard enough to fit cables in neatly, panel trunking just compounds this.

Can use stickybacks with cable ties, just wipe the board dwn first, so they stick properly

I use the stickybacks too, on the domestics it can get a bit fiddly :D
 
shouldn't the 2.5mm common fly leads be cream to denote the fact, that they themselves are functional earths ;). and without being a jobsworth it looks very neat think I may also steal :D as for the fine strands on the fly leads I put bootlace crimps on the ends and this seem to give them enough strength to be terminated in the relevant circuit terminal, then I use the this stuff.
View attachment 1401

Oh no! You are ABSOLUTELY right. I hadn’t thought of that. The terminals should maybe be cream too. It’s not going to get changed though, there are limits :)

I too am a huge fan of slotted trunking. Here’s some panels I made earlier, in Thailand for an AMX home automation project. It’s brilliant stuff for keeping cables in the right place, and for making alterations and additions easier.

Mechelec – Thanks, and yes, I was taking my time this morning: this job’s in my own house, so different standards apply! Doesn't really take long, though. And at the risk of sounding a boring old g!t, I find that doing things neatly often saves time overall in not having to chase mistakes later :)

OK and I think a well-finished TP DB is a gorgeous thing of beauty. Although, as my girlfriend says, perhaps that’s when it’s time for my injection :eek:
 

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shouldn't the 2.5mm common fly leads be cream to denote the fact, that they themselves are functional earths . ...
Hmm... I've slept on this one and changed my mind. NO, because the 2.5's and the DIN terminals are effectively an extension of the DB’s earthing arrangements and are therefore correctly designated G/Y.

The functional earths from the (removable) RCBOs (ie earth conductors which are current-carrying even under non-fault conditions), are correctly coloured cream, and equally correctly terminate at a G/Y arrangement!

The colour change has to occur somewhere, or one would get into a reductio ad absurdum argument, where the earth links should become cream all the way back to the service head, earth rod, or even sub-station neutral, whenever an RCBO or SMPS is used in an installation.

Your call :)

I’m enjoying this :)

What on earth is all that for in your house?????
Hi Jason

It’s from a house I built in Phuket, Thailand, which is now for sale. Those boxes were for power supplies and first-fix terminations for an AMX and Elan home-automation system. There was much more: it was an over-the-top proof-of-principle design. Everything was centrally-controllable and programmable in software via touch-screens: Aircon, 192 channels of lighting via Futronix digital dimmer panels, irrigation, ventilation fans, swimming pool, Tvs, 24 channels of distributed audio, security, room occupancy detection, biometric locks, CAT 5 network and even an attempt at voice control via a funky auto-switching Shure mic-controller. The latter idea was rubbish, don’t ever try it! I ripped it all out and sold the gear on EBay.

It was huge fun, all designed in my head, but to be honest with you I’m not actually a professional electrician. My real expertise is with bombs. But I’ve always liked to understand how things work.

Cheers

Mark Ribbands
 
About 5/6 years ago i was involved on a home automation ( tvs audio lighting security ) in edinburgh the pro kit these guys used didnt look half as neat as these tiland boxes you produced

as for having expertise with bombs thats not something Id advertise in a Forum open to the public M8y
 

Hmm... I've slept on this one and changed my mind. NO, because the 2.5's and the DIN terminals are effectively an extension of the DB’s earthing arrangements and are therefore correctly designated G/Y.

The functional earths from the (removable) RCBOs (ie earth conductors which are current-carrying even under non-fault conditions), are correctly coloured cream, and equally correctly terminate at a G/Y arrangement!

The colour change has to occur somewhere, or one would get into a reductio ad absurdum argument, where the earth links should become cream all the way back to the service head, earth rod, or even sub-station neutral, whenever an RCBO or SMPS is used in an installation.

Your call :)

I’m enjoying this :)

I hope it didn't keep you up all night :D to be perfectly honest If I were looking at it on an inspection, the fact you can quite clearly see the conductors along their whole length would be enough for me :D My personal preference would be always to have the correct fly lead in the correct numbered terminal for the circuit to eliminate confusion and make maintenance easier but you know and I know the chances of an RCBO going wrong are slim, so you wouldn't need to be doing it that often :D

Mogga check out his website on contact info, I would love to see how he chases out walls ;)
 
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lol Penny I mind a thread about drilling into stone walls problem SOLVED Call mr Cash n Dash lol

that aside Iv seen the tv programmes about demolition n blowing up tower blocks n the like Hunners n hunners o cables all over the shop STUFF that for a game of soldiers Ill stick to the nice easy stuff even upto 400swas tyvm
 
When my Dad used to blow stuff up for a living he got a bit confused with the quantities :D managed to take out all the windows in a nearby hospital:eek: don't know if I trust him to work with me:D customer could lose everything.
 
Wylex box I sid recently with 4 rcbo's.
If there had been any more than 4 I think i wouldve copied that idea
 

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