Is it acceptable to connect a radial to a spur via a 13A plug?

[Live&Learn]

Hello.

I hope you are all well. I've done a search but can't seem to see this addressed already, sorry.

I was at a business and I noticed they had a radial connected to a socket via a plug.

I understand you can add a radial (say 4 double sockets) on to a fused switched spur (off the ring), but what if that "fused switched" was just a 13A plug? To me technically that is the same but I'm not sure it is allowed to put a plug at the end of a radial.

Any thoughts please?

 

[pete01]

Cant see why not.

 

[plugwash]

Afaict it's not forbidden and there can sometimes be good reason to do it.

but care should be taken to ensure that the cable is suitable for the application and is adequately restrained.

 

[JohnW2]

I understand you can add a radial (say 4 double sockets) on to a fused switched spur (off the ring), but what if that "fused switched" was just a 13A plug? To me technically that is the same but I'm not sure it is allowed to put a plug at the end of a radial.

Some may regard it as a little 'naff' but, as has been said, there's no reason why you shouldn't do that.

As you say, electrically it's exactly the same as 'hardwiring' the spurred sockets via an FCU with a 13A fuse in it. Perhaps more to the point, it's not materially different from plugging in a multi-outlet 'extension cable' (of which countless millions are in service). Such extensions come with a means of attaching them to a wall, and it would be very silly if that were 'allowed' whereas it would not be 'allowed' if the sockets were, say, attached to the wall by surface pattress boxes!

 

[mikehammer69]

I would argue it's a somewhat unsuitable use case

A multi outlet extension with holes in the back is a random gadget of which there are many

A domestic plug usually connects appliances in the immediate vicinity ie; via ~2m lead where you can see what's being energized

Domestic sockets are usually connected to fixed wiring rather than energized possibly remotely via a plug

Operates the same in practice as a FCU if not unplugged so heyho anyway

 

[robinbanks]

So, notionally, one of these:

Any thoughts please?

Don’t worry about it. If they plug 8 kettles in and power them all up that fuse is a goner well before anything else sets on fire

 

[ebee]

Nothing in the overall principles prohibits it providing that all of the rules for safety apply, cable fit or purpose to carry the current and mechanically protected where appropriate etc . Yes might be considered ruf but hey ho providing no more dangerous than all the usual things we wouldn’t flinch at then no problem. Electricity is (potentially) dangerous but we obey certain rules to assist in mitigating those risks to an “acceptable” level. It is far more dangerous to allow a majority of people to drive cars in an insane manner without any due regard for everyone else.

 

[JohnW2]

I would argue it's a somewhat unsuitable use case

As I wrote, some people (perhaps even including myself to some extent) might intuitively regard it as 'naff' or 'rough', but I'm far from convinced that such is a particularly rational viewpoint. What makes you feel that it is "somewhat unsuitable"?

A multi outlet extension with holes in the back is a random gadget of which there are many .... A domestic plug usually connects appliances in the immediate vicinity ie; via ~2m lead where you can see what's being energized ... Domestic sockets are usually connected to fixed wiring rather than energized possibly remotely via a plug .... Operates the same in practice as a FCU if not unplugged so heyho anyway

All true - but if one is trying to be 'rational', that all begs the question "So what?".

 

[Ragnar_AT]

The main question is strain relief. I‘ve seen this a few times with standard pattress boxes and 20 mm of inner cores on show.

 

[plugwash]

The main question is strain relief. I‘ve seen this a few times with standard pattress boxes and 20 mm of inner cores on show.

Agreed. The cable needs to be adequately restrained such that it doesn't get ripped out of the socket. An extension socket gives you this "for free", an ordinary domestic socket on an ordinary patress box does not.

Another issue is what type of cable to use. T&E is less than ideal if moved frequently. flex is less than ideal in typical socket terminals. Ferrules are problematic if you want more than one wire in a terminal. Rapid fix sockets are a potential solution to this.

Another issue is resilience to damage. Regular domestic sockets in the UK are usually made of Urea-Formaldehyde which is hard wearing and fire resistant, but is a bit on the brittle side. Extension sockets are usually made of tougher materials.

I don't think any of these issues are show stoppers, just things to be taken into consideration.

So, notionally, one of these:

I do not recommend the UK version of the brenstuhl "super solid line" I have had one fail with the individual socket fronts breaking free of the body. Granted I abused the thing by opening the shutters and inserting Europlugs, but still even with such abuse I find the failure concerning.

 

[Murdochcat]

If it’s plugged in it’s not part of the fixed installation. It’s an extension lead

 

[SUNRAY]

If it’s plugged in it’s not part of the fixed installation. It’s an extension lead

Frequently been there before and not everyone agrees.

 

[SUNRAY]

Tonight I've been working on a system which consists of a number of multiway sockets which I haven't yet counted but about a dozen and all running on a single and 2 double sockets. Total load about 50 LED lights of 30 to 50 watts. In at least one place there are 3 in a chain and included in the middle of that is a standard single gang fixed socket (as is happens a PB box in the ceiling) which is supplied by a 13A plug plugged into a multiway.

 

[JohnW2]

Agreed. The cable needs to be adequately restrained such that it doesn't get ripped out of the socket. An extension socket gives you this "for free", an ordinary domestic socket on an ordinary patress box does not.

True, but that's equally true whether the other end of the cable is connected to an FCU or a plug.

If I understand correctly the situation described by the OP, the 'spurred sockets' are attached to a wall (or whatever), in which case I imagine that the cable would also be attached to the wall (or whatever), thereby providing the strain relief.

Another issue is what type of cable to use. T&E is less than ideal if moved frequently....

As above, I didn't think we were talking about a cable which would be 'moved' (at all). However, it's not necessarily totally easy to get T+E into a BS1363 plug.

... flex is less than ideal in typical socket terminals.

Is that really true? Is there not, in fact, an argument that stranded conductors are preferable to solid ones in screwed terminals?

Another issue is resilience to damage. Regular domestic sockets in the UK are usually made of Urea-Formaldehyde which is hard wearing and fire resistant, but is a bit on the brittle side. Extension sockets are usually made of tougher materials.

We're not talking about 'extension sockets' but (presumably) standard urea-formaldehyde resin ones. I (and others) only mentioned 'extension leads' to indicate that what the OP described is not materially different from ('ubiquitous') extension leads

I don't think any of these issues are show stoppers, just things to be taken into consideration.

Definitely agreed.

 

[JohnW2]

If it’s plugged in it’s not part of the fixed installation. It’s an extension lead

As we have seen, that's somewhat open to debate. If that were always true, it would presumably open up the possibility of all sorts of loopholes which people might try to exploit in order to evade the Wiring Regs

In any event, I think the scope for 'debate' is probably considerably reduced by this explicit statement in Approved Document P, which presumably reflects the intent of the authors of BS7671 ...