2 spurs from a Junction Box....worried?

[johnduffell]

where does it say there may be other means of meeting 433.1?

It doesn't have to say that specifically, you just have to meet it. Just because they gave a few options for free doesn't mean that's exhaustive. If you follow the guidance, you will definitely meet the regs, if not, you have to decide for yourself.
This is a very common pattern also used in all parts of the building regulations nowadays. The building regs just say something very hard to use, and the Approved Documents give specific examples that should cover most situations.

 

[johnduffell]

It doesn't say you shouldn't wire a banana form a junction box to a tomatoe in a ring final, dies that mean you can.

actually it specifically states they have to be copper conductors

but more generally, the regs are generally pretty clear about what standards cable, accessories and junction boxes must conform you.

 

[MFS Electrical]

It doesn't have to say that specifically, you just have to meet it. Just because they gave a few options for free doesn't mean that's exhaustive. If you follow the guidance, you will definitely meet the regs, if not, you have to decide for yourself.
This is a very common pattern also used in all parts of the building regulations nowadays. The building regs just say something very hard to use, and the Approved Documents give specific examples that should cover most situations.

Fair enough I’d be inclined to follow the regs though that way if you ever did end up on the chopping block you just point out the note at the front of the regs about complying with EAWR

 

[MFS Electrical]

Let me ask the question in another way...

You've just been asked to inspect the OPs property for an EICR and you find this junction box, it's been changed to a maintenance free one so that's no longer an issue.

How would you code the fact there are two spurs taken from the one junction box and what regulation would you quote to substantiate that coding?

C3 not to current standards citing reg 433.1 and mention Appx 15.
I think the wording is quite clear in saying that Appx15 is showing the design options. As in the options on how to spur from a ring rather than the diagram being one of many different options.

Out of interest how would you justify not coding it?

 

[johnduffell]

C3 not to current standards

c3 is actually "improvement recommended" (as it would improve the safety of the installation) According to Electrical Safety Council’s Best Practice Guide 4,

So in fact, even if it were non compliant, it shouldn't be the subject of a classification code unless it affects the safety of the installation.

 

[MFS Electrical]

c3 is actually "improvement recommended" (as it would improve the safety of the installation) According to Electrical Safety Council’s Best Practice Guide 4,
View attachment 45070
So in fact, even if it were non compliant, it shouldn't be the subject of a classification code unless it affects the safety of the installation.

Nice catch id still C3 it because it could affect the safety of an installation there may even be an argument for a C2 because it could be potentially dangerous,in the event of an overload

 

[SparkyChick]

Very rare I disagree with your stance on electrics but I think your enterpretation based on if it doesn't say you can't do something in the regs then you can do it.

It doesn't say you shouldn't wire a banana form a junction box to a tomatoe in a ring final, dies that mean you can.

433.1 says what you can do.

Thank you for those kind words.

I think my hard line stance makes it come across that way, but that's not really what I'm getting at.

In the course of this thread, I've read 433.1 several times and it makes no mention of junction boxes. It's focus is on cable loadings and ensuring that they are adequately protected against overload through the correct selection of cable size and appropriate OCPD.

Specifically 433.1.204 states the rules for cable sizing for ring finals.

Since these two spurs are designed correctly, i.e. the correct size cable and only one double socket outlet on the end of each, the spurs themselves comply. The ring final itself complies because it is wired in an appropriate cable and protected by an appropriate OCPD.

So the three elements here comply in their own right. Providing the junction box used can handle the expected load (whether or not this is accessible is another discussion), there is no reason that I can see how this arrangement can be deemed to be a non-compliance.

The appendix 15 argument if taken to it's logical conclusion means you can never have a single socket outlet on a ring final, or take a spur from the origin, or have more than two double socket outlets after a fused spur, or have a grid switch system... why? Because they aren't shown on the diagram. The diagram provide guidance on how to comply, it's not a definitive list of what you can do (as it states, the diagram shows options).

And part of why I'm taking a somewhat hard line stance is because I'd like to see more substantiated 'it's against regs'. If I make statements to that effect I try and provide appropriate regulation numbers as it may help someone understand more. And in this case, no body has been able to explain to me how this arrangement doesn't comply without resorting to the appendix 15 argument.

 

[SparkyChick]

C3 not to current standards citing reg 433.1 and mention Appx 15.
I think the wording is quite clear in saying that Appx15 is showing the design options. As in the options on how to spur from a ring rather than the diagram being one of many different options.

Out of interest how would you justify not coding it?

At the moment, I couldn't justify a code because I genuinely do not believe it contravenes any of the regulations in 433.1. Hence why I'm asking which regulation it contravenes and why.

I would possibly inspect it and look for signs of thermal damage to the junction box and the cabling that may suggest an overload situation, but the arrangement itself whilst a little unorthodox doesn't appear to breach 433.1 for the reasons I've outlined above.

 

[Lucien Nunes]

id still C3 it because it could affect the safety of an installation there may even be an argument for a C2 because it could be potentially dangerous,in the event of an overload

Nooooo! Not the overload argument again!

There is no more risk of overload with what the OP has done, than with two spurs taken from different points on the ring. Subject to the junction box making a sound connection, which is a caveat we've been accepting all along.

I will state categorically that this method is just as safe as any other. The only debate is about whether it technically complies as a configuration, which I think it does.

 

[MFS Electrical]

Thank you for those kind words.

I think my hard line stance makes it come across that way, but that's not really what I'm getting at.

In the course of this thread, I've read 433.1 several times and it makes no mention of junction boxes. It's focus is on cable loadings and ensuring that they are adequately protected against overload through the correct selection of cable size and appropriate OCPD.

Specifically 433.1.204 states the rules for cable sizing for ring finals.

Since these two spurs are designed correctly, i.e. the correct size cable and only one double socket outlet on the end of each, the spurs themselves comply. The ring final itself complies because it is wired in an appropriate cable and protected by an appropriate OCPD.

So the three elements here comply in their own right. Providing the junction box used can handle the expected load (whether or not this is accessible is another discussion), there is no reason that I can see how this arrangement can be deemed to be a non-compliance.

The appendix 15 argument if taken to it's logical conclusion means you can never have a single socket outlet on a ring final, or take a spur from the origin, or have more than two double socket outlets after a fused spur, or have a grid switch system... why? Because they aren't shown on the diagram. The diagram provide guidance on how to comply, it's not a definitive list of what you can do (as it states, the diagram shows options).

And part of why I'm taking a somewhat hard line stance is because I'd like to see more substantiated 'it's against regs'. If I make statements to that effect I try and provide appropriate regulation numbers as it may help someone understand more. And in this case, no body has been able to explain to me how this arrangement doesn't comply without resorting to the appendix 15 argument.

In that case it may well be technically compliant because there isn’t a reg forbidding it so it’s wrong because it just is good point about the grid switches etc hadn’t thought of that.

Nooooo! Not the overload argument again!

There is no more risk of overload with what the OP has done, than with two spurs taken from different points on the ring. Subject to the junction box making a sound connection, which is a caveat we've been accepting all along.

I will state categorically that this method is just as safe as any other. The only debate is about whether it technically complies as a configuration, which I think it does.

I was thinking more overloading the actual junction box itself rather than the wiring... but I do see your point potentially anything could be plugged into any socket and cause an overload anywhere