socket

[Buzz-light-bulb]

Little scenario for you all.

I've been doing an eicr today and come across a double socket wired as a radial on a 2.5mm t-e, which is protected by a 32 amp rcbo.
Technically this cannot overload as the cable can withstand 27 amp ref method c. Unless mr DIY comes along and starts adding new sockets which I am not responsible for so my question is would you leave it

 

[Geoffsd]

I was questioning the 32A bit more than the RCBO bit - if the maximum the plugtop fuses will allow you to draw is 26A why would you 'need' a 32A OCPD, especially considering the maximum current rating of the cable is 27A?

I was answering that.
A 32A MCB would do the same.

This seems to be the argument - does one cable coming out of the RCBO make it a radial, or is it 'just the same as' spurring off a 32A ring final, even though it isn't the same because there isn't a ring final there?

Both. Move one of the rings to this RCBO if you would then think it acceptable and 'normal'.

With a 2.5mm ring you might want a 32A OCPD to avoid 'nuisance tripping' due to a larger number of sockets,

Ok, but on a ring your only allowed a 32A OCPD.

but in what kind of situation would you need to be able to draw anything near 20A from one double socket?

So the cable won't be overloaded, then? Q.E.D.

If there is a reason for needing so much current I would expect there to be a need for more sockets, which would invalidate the argument that it's 'just the same as' spurring off a 32A ring.

I think this is where you are confused.
Current is drawn by the load. A 32A OCPD won't allow more to 'leak' through and damage the cable.

This sounds like installing something not because you need it but because you've found some loophole in the regs and using it as an argument for it being 'allowed'; IMO the question should be 'why would you'?

I don't think anyone would design it as such form scratch but it is fully compliant with the regulations.

I can't picture what it is but there might have been a good reason for doing this; on the other hand someone might have done it because as far as they knew sockets go on a 32A OCPD, in which case it should probably be changed for a 20A to avoid unnecessary confusion.

I believe someone said 'we don't have to design for numpties'.

You could if you want.

I note (I think) no one has complained that the cable is too small.

 

[NickD]

In what kind of situation would you need to be able to draw anything near 20A from one double socket?

On a cold winter day (3kW heater) when your hair's wet (2kW hairdryer).

 

[Adam W]

I note (I think) no one has complained that the cable is too small.

Generally speaking the cable would be harder to replace than the RCBO, hence why the discussion has centred around changing the RCBO.

 

[mobile]

coding

I wouldn't code it but would add a comment on cert to cover myself. Your only testing the system for safety as it stands at present time not what some moron might do in future, that's a slippery slope to insanity.

 

[Adam W]

I note (I think) no one has complained that the cable is too small.

Generally speaking the cable would be harder to replace than the RCBO, hence why the discussion has centred around changing the RCBO.

 

[Adam W]

On a cold winter day (3kW heater) when your hair's wet (2kW hairdryer).

You could say that about any 20A radial, never mind one with only 1 socket on it.

 

[Hawkmoon]

The only reason I would even consider mentioning it on the form is to prevent some misinformed electrician/whoever in the future bad mouthing me to the customer, saying that I should have picked it up as a defect.

My entry would discuss its compliance, with no recommendations.

 

[NickD]

Returning to an earlier poster's (somewhat overlooked?) point:-

https://www.google.co.uk/search?q=unfused+2+way+adapter&tbm=shop

Unfused 2-way adaptors readily available to buy now cheaply and which will be 'in the wild' for decades. 82 year old Mrs Scroggins buys one and plugs three 3kW heaters into her landing double socket, one for each bedroom. Potential 39A draw on a 27A cable protected by Type B 32A 60898 / 61009. Trip time at 39A is way off the curves, so in excess of 2.5 hours, if ever, during which time the cable is being exposed to about double its permitted heating power.

Yes I appreciate it's exactly the same problem if the socket is a spur off the ring.

 

[dazza1981]

Returning to an earlier poster's (somewhat overlooked?) point:-

https://www.google.co.uk/search?q=unfused+2+way+adapter&tbm=shop

Unfused 2-way adaptors readily available to buy now cheaply and which will be 'in the wild' for decades. 82 year old Mrs Scroggins buys one and plugs three 3kW heaters into her landing double socket, one for each bedroom. Potential 39A draw on a 27A cable protected by Type B 32A 60898 / 61009. Trip time at 39A is way off the curves, so in excess of 2.5 hours, if ever, during which time the cable is being exposed to about double its permitted heating power.

Mrs scrogging needs to use her noggin...... but i see what your saying !!!

 

[NickD]

She bought the adaptor on the high street having confirmed it was BS rated. She bought her heaters new from Argos. She has bodged nothing.

 

[GLENNSPARK]

Returning to an earlier poster's (somewhat overlooked?) point:-

https://www.google.co.uk/search?q=unfused+2+way+adapter&tbm=shop

Unfused 2-way adaptors readily available to buy now cheaply and which will be 'in the wild' for decades. 82 year old Mrs Scroggins buys one and plugs three 3kW heaters into her landing double socket, one for each bedroom. Potential 39A draw on a 27A cable protected by Type B 32A 60898 / 61009. Trip time at 39A is way off the curves, so in excess of 2.5 hours, if ever, during which time the cable is being exposed to about double its permitted heating power.

Yes I appreciate it's exactly the same problem if the socket is a spur off the ring.

assess likely usage.

but as i says...you can note it...no code.

 

[GLENNSPARK]

I think there's a danger of confusing "Is this an absolute top-notch covered-all-the-bases, cable-cannot-be-rogered-by-incompetent-additions-or-rogue-equipment design?" with "Does it actually require improvement and if so on what grounds, preferably supported by the regs?"

?????

what do you work to then nick?

 

[GLENNSPARK]

Then again we are told to flag up "Some circuits which require RCD protection under the current regs have none" as a C3...does that require​ improvement?...my brain hurts.

thats about additional protection....not overload...

 

[shanky887614]

?????

what do you work to then nick?

He works to mr cockburns books

 

[telectrix]

He works to mr cockburns books

that'll be OK then, as it's bonded to the metal window handles.