New Electrical circuit. Suggestions for a "HUB"

I reckon that it would mean that the 'capacity' statement was incorrect. If the 'capacity' was 60 litres, to my mind that means that one can't get 65 litres into it.
Presicely, so if you can get 4 x 2.5 in ...


No-one, not even the technical support guy at MK I spoke to, seems to know what 'socket outlet' means in that context - i.e. whether a double socket has one or two 'socket outlets'!!
A two gang is known as a 'double socket outlet'

'the man from MK' was just as confused as the rest of us (saying that the specs were written by the marketing dept!!)
Fair enough.

Do many companies assign the listing of Technical Specifications to the Marketing Department.
 
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I reckon that it would mean that the 'capacity' statement was incorrect. If the 'capacity' was 60 litres, to my mind that means that one can't get 65 litres into it.
Presicely, so if you can get 4 x 2.5 in ...
As I said, I don't recall having seen this sort of argument about 'manufacturer's documentation' before. I have always thought that those who feel constrained by the regs "to follow the MIs" would feel that they had to 'comply with' things in manufacturer's documents such as the 'terminal capacities' we are discussing - don't you think they would?

I would have though that 'rating' (e.g. current rating 'or 'voltage rating) is no more 'an instruction' than is 'capacity' - it usually merely relates to what sort of tests have been undertaken. We all know that, for example, cables intended for ELV use etc. can usually tolerate voltges far in excess of their 'voltage ratings', but I don't thing many would feel that they were complying with BS7671 if they 'ignored' that aspect of the manufacturer's documentation.

Life will be rather different if the proposed change in what BS7671 says about MIs comes into force next year.
No-one, not even the technical support guy at MK I spoke to, seems to know what 'socket outlet' means in that context - i.e. whether a double socket has one or two 'socket outlets'!!
A two gang is known as a 'double socket outlet'
Maybe, but that doesn't really make it any clearer as to whether a 'double socket outlet' is 'one socket outlet' or 'two socket outlets'. The document we're looking at doesn't use that terminology - it talks about "3 gang", not "triple socket outlet" or anything like that.
Do many companies assign the listing of Technical Specifications to the Marketing Department.
Goodness knows - as I reported at the time, 'the man from MK' seemed as surprised by, and as unhappy with, this as I was. The one thing he seemed clear about was that it was not safe for an MK double socket to supply 2 x 13A loads for long periods of time.

Kind Regards, John
 
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3. You do not 'hub' electrical circuits, its either a ring, or a radial. In both cases, the wiring goes from socket to socket, not to a central spider point.

Although ironically, the more conventional use of the word "radial" is to describe distribution from a central point.
 
3. You do not 'hub' electrical circuits, its either a ring, or a radial. In both cases, the wiring goes from socket to socket, not to a central spider point.
Although ironically, the more conventional use of the word "radial" is to describe distribution from a central point.
Indeed - and I have certainly seen at least partially 'star-wired' radial circuits. There is nothing non-compliant about the concept.

Kind Regards, John
 
Apologies. I was being rather 'general' in my description. I was trying to direct the OP to the usual way of installing a radial circuit.

I note that the 'regs' does not show a spider arrangement for a radial circuit.

But yes, any arrangement of any number of electrical points on a single circuit can be described as a radial, providing the circuit does not finally meander its way back to the consumer unit again.
 
Apologies. I was being rather 'general' in my description. I was trying to direct the OP to the usual way of installing a radial circuit.
I realise that, and wasn't criticising you - I was merely responding to a follow-up comment.
I note that the 'regs' does not show a spider arrangement for a radial circuit.
True (depending, I suppose,on how you define 'a spider arrangement'), but the couple of examples of radial circuits it shows in Appendix 15 do at least have multiple branches, some originating from JBs.

Kind Regards, John
 
This "hub" was in a friend's house behind a hinged panel just below the ceiling in the hall.


Several of the JBs were wired as a ring final about 25 feet from the CU. From each of these ringed JBs was a cable to a socket.

Other JBs were involved in lighting. Even the door bell ( ELV ) was wired via the JB at the end.
 
I don't suppose you can dispute that they are "accessible for inspection" :)

The star is an interesting circuit design and could in theory be advantageous if it allows convenient cable routes.

<thought experiment>
Does anyone see anything wrong with running 4mm t&e to a JB, then 2.5mm t&e out to the sockets to create a 32A circuit without the problems associated with broken rings or having to run a 4mm radial? I guess that only supplies 20A per socket but that's no different from spurring. The big issues I suppose is that it creates this problem with every socket and also finding a JB suitable would be a major PITA.
</thought experiment>
 
But yes, any arrangement of any number of electrical points on a single circuit can be described as a radial, providing the circuit does not finally meander its way back to the consumer unit again.

I envisage a feed from CU to JB, then from the JB to each socket, with every socket then looping back to the JB. A "Rings Final Circuit" or "Olympic Rings Final Circuit" or maybe a "Spirograph Final Circuit". With an uber junction box in the centre, the Lord of the Rings.
 
Does anyone see anything wrong with running 4mm t&e to a JB, then 2.5mm t&e out to the sockets to create a 32A circuit without the problems associated with broken rings or having to run a 4mm radial?
Provided each 2.5mm² only feeds one socket (single or double), that sounds to me like a perfectly acceptable 32A radial circuit - provided you could find, or improvise, an appropriate JB.

Kind Regards, John
 
<thought experiment>
Does anyone see anything wrong with running 4mm t&e to a JB, then 2.5mm t&e out to the sockets to create a 32A circuit without the problems associated with broken rings or having to run a 4mm radial? I guess that only supplies 20A per socket but that's no different from spurring. The big issues I suppose is that it creates this problem with every socket and also finding a JB suitable would be a major PITA.
</thought experiment>
No need for JBs, just put the main consumer unit or other distribution panel in there, with one circuit for each outlet.
 
Yeah a star circuit would definitely be more convenient from the perspective of cable routing.

However it's also more problematic to have installed by what I'm to understand and it's not what any future sparks/residents would expect so I'll stick with tradition and do it the time tested way.

I have actually found an outlet in the far end of my main living room I didn't know even existed which is actually pretty funny. As the living room is next door to this "project room" I'm going to start there with radial add-on as it's on the same wall

I'll Then use the existing single outlet in the "project room" and do the same. This means I can cover 2/4 walls from existing outlets.

That should give the some 6 odd new outlets I require.

All the walls are brick here so I really hope existing channeling is in place for the wires
 
Yeah a star circuit would definitely be more convenient from the perspective of cable routing. However it's also more problematic to have installed by what I'm to understand and it's not what any future sparks/residents would expect so I'll stick with tradition and do it the time tested way.
It's obviously your decision but, if a 'star' arrangement (from a 'hub') of a radial circuit would be more convenient to install, as has been discussed here, there's nothing electrically wrong with it (provided it's done correctly). If you could find an electrician who actually understands electrical installations (rather than just cookbooks and regulations), (s)he ought to be prepared to install such a circuit (if they agree it's the most convenient way to do things) - and provided it was adequately documented, it should not really be a problem for a competent electrician in the future, either.
I have actually found an outlet in the far end of my main living room I didn't know even existed which is actually pretty funny. As the living room is next door to this "project room" I'm going to start there with radial add-on as it's on the same wall ... I'll Then use the existing single outlet in the "project room" and do the same. This means I can cover 2/4 walls from existing outlets. ... That should give the some 6 odd new outlets I require.
I'm not totally sure what you are saying here - if you are talking about extending existing circuits, without any intervening fuses (which would limit all new sockets on the extension to 13A total load), you could only do as you describe if the existing circuits are radial (not ring) ones protected by a fuse/MCB no greater than 20A.

Kind Regards, John
 

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