Trailing Socket?

[JohnW2]

The fact that it's a white plastic box doesn't have to mean there is no cable restraint.

As your photo illustrates, that is strictly true, but I would suggest that it is probably very unlikely that a person who was happy to leave a socket attached to a pattress box lying loose on the floor would bother to hunt out one of those very few boxes which does have cable restraint.

Kind Regards, John

 

[plugwash]

I don't think there is much "possibly" about it - that reg explicitly reaquires that there should be "no appreciable strain" on connections

And yet we all wire our houses using solid core cable and accessories that have to be wired up before they are put into place, inevitablly putting strain on the connections when the accessory is pushed into place.

 

[ban-all-sheds]

Prepping cables to insert into a socket and then pushing that socket into a back box puts more strain on the conductors and terminals than a trailing socket as described, and that can happen multiple times over the life of the circuit.

 

[JohnW2]

And yet we all wire our houses using solid core cable and accessories that have to be wired up before they are put into place, inevitablly putting strain on the connections when the accessory is pushed into place.

We do (well, apply stress, which could possibly result in 'strain'), and it's not something I'm totally comfortable about - I doubt that I'm the only person who has occasionally seen the consequences of that. However, I'm not sure that there is any realistic alternative - since neither a widespread change to the use of stranded conductors and/or much deeper back boxes would really be realistic.

However, I'm not sure that the fact that stress (hence potential strain) is essentially unavoidable in that situation is a viable excuse for not providing aspects of strain relief when it can be done effectively.

Kind Regards, John

 

[ban-all-sheds]

I agree it's not an excuse.

But which regulation is it not an excuse for contravening except 134.1.1?

 

[JohnW2]

As above, 526.6

 

[ban-all-sheds]

In that case, as I and plug have pointed out, every act of installing a socket (and most other accessories) contravenes the regulations.

 

[JohnW2]

Exactly - but, as I said, the fact that one has little choice but to run the risk of contravening that regulation whenever one installs an accessory, that is not (as I thought had been agreed) an excuse for not complying with the regulation when one can.

 

[ban-all-sheds]

But the regulation has no clauses relating to whether there is a choice or not.

 

[JohnW2]

No-one said it did - and that is the reason why one risks contravening the regulation when installing accessories. I really don't think you are actually condoning the omission of strain relief when it is practical to provide it - so again we seem to have a case of arguing for the sake of arguing. I'm out.

 

[ban-all-sheds]

I'm not condoning it, but I don't see how it can be a contravention of 526.6.

You're developing a bit of a habit of branding anybody who doesn't change their mind and agree with you after a few posts as "arguing for the sake of it".

 

[JohnW2]

Since, what 526.6 "actually says" includes no exceptions for connections in particular circumstances, it appears to require that no connection be subjected to "appreciable mechanical strain". In a situation in which 'mechanical stress' will inevitably be applied to connections (e.g. when pushing connections to an accessory into a back box) , the only way of ensuring that such stress does not result in "appreciable strain" would be to employ some appropriate means of 'strain relief'. Since that is very rarely practical/possible with accessories, we don't do it, but that doesn't alter the fact that such an omission constitutes a contravention of what 526.6 "actually says/requires". Just as with "non-combustible CUs", a regulation should not require something which is 'impossible', but this one appears to do that.

 

[EFLImpudence]

It depends, I suppose, on whether you think fitting a faceplate, which you have connected, places any strain, by definition, on the connections.

 

[JohnW2]

It depends, I suppose, on whether you think fitting a faceplate, which you have connected, places any strain, by definition, on the connections.

As was said by those who started this line of discussion, with solid conductors and normal sized back boxes, it is inevitable that there will be some 'mechanical stress' on the connections. Whether that stress results in "appreciable strain" on the connections depends upon a host of factors (not the least being the definition of "appreciable"!), but it's certainly far from impossible.

As I said before, I rather doubt that I am the only person who has ever experienced the phenomenon of a seemingly satisfactory connection to an accessory 'going wrong' (loosening, or even 'coming out') after the accessory and its connections have been 'pushed back' into the back box (particularly with higher-CSA solid conductors) - and, if/when that happens, it is presumably 'proof' that "appreciable strain" has been applied to the connections.

However, as I've said, the recent line of the comments seems to have got a little silly since, even if it can be argued that, strictly speaking, one cannot ensure compliance with 526.6 in some situations, I don't see that as a reason/excuse for not complying in other situations in which compliance is straightforward.

Kind Regards, John

 

[DetlefSchmitz]

This is really silly. If a wire comes loose while you are pushing an accessory into a back box, it is because you didn't make the connection correctly, and you didn't give it a good tug, which should put way more 'strain' on the wire as a deliberate test. If you did do it properly then this is the last time it will be strained for a long time.

It must be evident that this is outside the scope of the quoted regulations. Sometimes people seem obsessed with trivia. The regulations book is not really a bible, just a best effort by a random group of self interested 'experts'. It really doesn't bear this detailed analysis.