Wiki entry on Junction Boxes

[JohnW2]

The wiki entry on Junction Boxes (here) relies heavily on a link to Ashley's booklet entitled "Junction Box Guide to 17th Edition" (here).

Although it contains plenty of useful information, this 'guide' builds up to, and I presume is designed to promote, Ashley's "Maintenance Free Connections" (as described on p10 of the guide). The guide very strongly implies (virtually says) that use of these products in inaccessible locations is acceptable in terms of BS7671:2008. I honestly can see no reason to believe that is true, in which case this is potentially misleading, and maybe the wiki should be at least annotated to that effect?

Kind Regards, John.

 

[westie101]

Unless provision is made for access, where boarding, carpet or other
similar covering is laid over a junction box with screw terminals, it
may not be considered accessible and maintenance free terminals
should be used.

This drew my attention, it seems that as long as provision is made for access (e.g. a floor trap in a wooden floor under a carpet) screw type can be acceptable. If no means of access is made and one has to be made at a future date screw terminals cannot be used but maintenance free types can!

 

[JohnW2]

Unless provision is made for access, where boarding, carpet or other
similar covering is laid over a junction box with screw terminals, it
may not be considered accessible and maintenance free terminals
should be used.

This drew my attention, it seems that as long as provision is made for access (e.g. a floor trap in a wooden floor under a carpet) screw type can be acceptable. If no means of access is made and one has to be made at a future date screw terminals cannot be used but maintenance free types can!

Interesting. Where did that come from? Except for special situations which do not apply here, BS7671:2008 (526.3) only allows joints in non-accessible locations if they are made by "welding, soldering, brazing or a suitable compression tool" - and I can't see that the Ashley "maintenance free" product comes into any of those categories.

Kind Regards, John.

 

[ban-all-sheds]

maybe the wiki should be at least annotated to that effect?

DIYnot.com Wiki

What is a Wiki?

A wiki is a website where users can add, remove, and edit every page using a web browser. It is like an encyclopedia that anyone can edit and contribute towards.

 

[JohnW2]

What is a Wiki?
A wiki is a website where users can add, remove, and edit every page using a web browser. It is like an encyclopedia that anyone can edit and contribute towards.

Needless to say, I know that

I just though that, since you were the person who wrote it and 'majored on' the link to this potentially misleading 'guide', you might like to deal with it. However, if you'd prefer me to do it, I will.

Kind Regards, John.

 

[sparkiemike]

Unless provision is made for access, where boarding, carpet or other
similar covering is laid over a junction box with screw terminals, it
may not be considered accessible and maintenance free terminals
should be used.

This drew my attention, it seems that as long as provision is made for access (e.g. a floor trap in a wooden floor under a carpet) screw type can be acceptable. If no means of access is made and one has to be made at a future date screw terminals cannot be used but maintenance free types can!

Interesting. Where did that come from? Except for special situations which do not apply here, BS7671:2008 (526.3) only allows joints in non-accessible locations if they are made by "welding, soldering, brazing or a suitable compression tool" - and I can't see that the Ashley "maintenance free" product comes into any of those categories.

Kind Regards, John.

Ashley/Hager did have a FAQ on this issue on their website, I can't find it, but did keep a copy for my records.

FAQ: MAINTENANCE FREE JUNCTION BOX

Q: How does the Ashley Maintenance Free Junction Box enable compliance with regulation 526.3 in BS 7671: 2008?

A: Regulation 526.3 identifies exceptions from the requirement for connections to be accessible for inspection, testing and maintenance, one exception being a joint forming part of the equipment complying with the appropriate product standard.

Equipment is covered by the definition of electrical equipment, which includes any item for such purposes as generation, conversion, transmission, distribution or utilisation of electrical energy, such as accessories.

An appropriate product standard would validate that inspection, testing and maintenance is not required. Appendix 15 of BS 7671 provides additional information with respect to the intent of 526.3 i.e. “use maintenance-free terminals / connections”.

The Ashley Maintenance Free Junction Box has passed tests from appropriate product standard(s) including:
:- long term connection test to ensure continued performance over time
:- voltage drop to verify the integrity of the joint
:- temperature rise to verify the joint does not overheat
:- corrosive atmospheres: sulphur dioxide test & salt mist to prove there is no degradation of the joint due to corrosion
:- vibration to prove there is no degradation of the joint due to movement
:- shock to prove there is no degradation of the joint due to shock waves
:- short-time withstand current (short-circuit) to prove there is no degradation of the joint due to fault currents
:- pull out to prove the connection has sufficient retention means
:- Load cycling test to prove there is no degradation of the joint due to heating and cooling.

When installed in accordance with manufacturer’s instructions in a circuit complying with BS 7671, the Ashley Maintenance Free Junction Box does not require further inspection, testing and maintenance and therefore enables compliance with the intent of regulation 526.3.

In addition to the above tests the Ashley Maintenance Free Junction Box complies with BS EN 60670-22 which covers Junction boxes.

 

[ericmark]

134.1.1 Good workmanship by competent persons or persons under their supervision and proper materials shall be used in the erection of the electrical installation. Electrical equipment shall be installed in accordance with the instructions provided by the manufacturer of the equipment.

If the manufacturer says it's maintenance free then it is maintenance free. Simple.

The idea of spring loading connections has been around for a long time. 1984 I was using spring loaded earth connections with SWA epoxy resin cable joints and I will admit I did not have much faith and would have preferred a jubilee clip. But I have not to date found there to be a problem.

The spring loaded connection blocks started arriving with German equipment around 1990 and again I did not like them. But I have seen many wires necked off where repeated maintenance has finally taken it's toll and also the problem with lose connections which prompted the checking of wires in screw connections but again as yet not found a problem with a correctly inserted spring type terminal.

So I reluctantly have to admit the spring retention of wired works.

What is assessable? Have pry bar will investigate. OK epoxy resin does make it in-assessable but under carpets, and floor boards does not stop one having assess it just makes it harder.

When building Sizewell power station some items were installed then the concrete wall was completed when I said what happens if it needs replacing the answer was simple. Knock down the wall. If behind a 2 foot thick concrete wall is assessable then what is counted as not being assessable?

 

[JohnW2]

[Ashley/Hager did have a FAQ on this issue on their website, I can't find it, but did keep a copy for my records.

Thanks. I have to say that it sounds like very iffy wriggling to me....

....one exception being a joint forming part of the equipment complying with the appropriate product standard.
.....
When installed in accordance with manufacturer’s instructions in a circuit complying with BS 7671, the Ashley Maintenance Free Junction Box does not require further inspection, testing and maintenance and therefore enables compliance with the intent of regulation 526.3.

I really don't see that this is within the spirit (or probably word) of 526.3(v). To the best of my knowledge there is no specific standard for JBs with maintenance-free connections, so there is really no "appropriate product standard" with which to satisfy 526.3(v). Ashely's FAQ goes on to mention that their product complies with BS EN 60670-22 which covers Junction boxes, but that is surely irrelevant, since that's a general standard which screw-terminal JBs also comply with.

Whilst it could well be that the Ashely/Hager product actually is reliable enough to be inaccessible, I'm extremely sceptical as to whether use of them in non-accessible locations would be compliant with BS7671- what do others think?

Kind Regards, John.

 

[westie101]

All joints made on our system a screw connectors in resin joint shells (OK most are snap off designed to break at a specific torque) off course they are then buried!
(fair enough if they fail we just replace one joint with,.usually, two)

Earth connections are by roll springs onto lead sheaths

Older overhead connectors were a spring grip type, still in use and still available.

It is quite common for legislation not to set a specific standard but outline a requirement, so if one company has designed something, that sort of sets the standard. As long as they have comprehensively tested their design and ensured it meets any requirements (and no doubt talked to the relevant authorities) there is nothing wrong with that.
We see and use a lot of equipment that came through this route.

 

[JohnW2]

All joints made on our system a screw connectors in resin joint shells (OK most are snap off designed to break at a specific torque) off course they are then buried!

Even in terms of BS7671, "joints designed to be buried" are exempt from the accessibility requirement {526.3(i)}, together with compound-filled or encapsulated joints {526.3(ii)}.

All It is quite common for legislation not to set a specific standard but outline a requirement, so if one company has designed something, that sort of sets the standard. As long as they have comprehensively tested their design and ensured it meets any requirements (and no doubt talked to the relevant authorities) there is nothing wrong with that. We see and use a lot of equipment that came through this route.

I agree with all that, but somewhat doubt that it applies in the case we are talking about - and I very much doubt that Ashley/Hager will have discussed their product with any relevant authorities (apart from anything else, if they had received the blessing of authorities, they'd surely be boasting about that in their promotion?!).

Kind Regards, John.

 

[westie101]

apart from anything else, if they had received the blessing of authorities, they'd surely be boasting about that in their promotion?!).

Having talked to folk who have been directly involved with such things, the authorities never give things their blessing (they have no standard to compare things to) but similarly never condemn them (it keeps them in the clear if things go wrong). They do however unofficially discuss them and give pointers. Manufacturers can't then involve the authority in any advertising.

 

[ban-all-sheds]

FAQ: MAINTENANCE FREE JUNCTION BOX

Q: How does the Ashley Maintenance Free Junction Box enable compliance with regulation 526.3 in BS 7671: 2008?

A: Regulation 526.3 identifies exceptions from the requirement for connections to be accessible for inspection, testing and maintenance, one exception being a joint forming part of the equipment complying with the appropriate product standard.

Equipment is covered by the definition of electrical equipment, which includes any item for such purposes as generation, conversion, transmission, distribution or utilisation of electrical energy, such as accessories.

An appropriate product standard would validate that inspection, testing and maintenance is not required. Appendix 15 of BS 7671 provides additional information with respect to the intent of 526.3 i.e. “use maintenance-free terminals / connections”.

The Ashley Maintenance Free Junction Box has passed tests from appropriate product standard(s) including:
:- long term connection test to ensure continued performance over time
:- voltage drop to verify the integrity of the joint
:- temperature rise to verify the joint does not overheat
:- corrosive atmospheres: sulphur dioxide test & salt mist to prove there is no degradation of the joint due to corrosion
:- vibration to prove there is no degradation of the joint due to movement
:- shock to prove there is no degradation of the joint due to shock waves
:- short-time withstand current (short-circuit) to prove there is no degradation of the joint due to fault currents
:- pull out to prove the connection has sufficient retention means
:- Load cycling test to prove there is no degradation of the joint due to heating and cooling.

When installed in accordance with manufacturer’s instructions in a circuit complying with BS 7671, the Ashley Maintenance Free Junction Box does not require further inspection, testing and maintenance and therefore enables compliance with the intent of regulation 526.3.

Sorry, but IMO that's just b****cks.

To say well this aspect complies with that standard, and this other aspect complies with this other standard, therefore this JB qualifies as "a joint forming part of the equipment complying with the appropriate product standard" is self-serving cynical nonsense, spouted for commercial gain.

A triumph of marketing over engineering, which they know they'll get away with because enough people will assume that if they wrote it it must be true.

 

[ban-all-sheds]

134.1.1 Good workmanship by competent persons or persons under their supervision and proper materials shall be used in the erection of the electrical installation. Electrical equipment shall be installed in accordance with the instructions provided by the manufacturer of the equipment.

If the manufacturer says it's maintenance free then it is maintenance free. Simple.

Equally simple is that 526.3 does not exempt "maintenance free" junction boxes..

IMO they do not comply, and were I ever to do a PIR and find them I'd code it accordingly.

 

[JohnW2]

Sorry, but IMO that's just b****cks.
To say well this aspect complies with that standard, and this other aspect complies with this other standard, therefore this JB qualifies as "a joint forming part of the equipment complying with the appropriate product standard" is self-serving cynical nonsense, spouted for commercial gain.
A triumph of marketing over engineering, which they know they'll get away with because enough people will assume that if they wrote it it must be true.

As you will realise from the response I gave, I agree totally, even if my wording was perhaps a little less forceful.

When I started this thread, I rather assumed that there was not going to be any support for the notion that use of the Ashley/Hager product in an inaccessible location would be compliant with BS7671. However, if there is going to be a 'debate', I guess we'd better wait for it to reach some sort of conclusion before either of us thinks about annotating the wiki!

Kind Regards, John.

 

[sparkiemike]

Thanks. I have to say that it sounds like very iffy wriggling to me....

Don't know what that means... me or Hager?

....one exception being a joint forming part of the equipment complying with the appropriate product standard.
.....
When installed in accordance with manufacturer’s instructions in a circuit complying with BS 7671, the Ashley Maintenance Free Junction Box does not require further inspection, testing and maintenance and therefore enables compliance with the intent of regulation 526.3.
I really don't see that this is within the spirit (or probably word) of 526.3(v). To the best of my knowledge there is no specific standard for JBs with maintenance-free connections, so there is really no "appropriate product standard" with which to satisfy 526.3(v). Ashely's FAQ goes on to mention that their product complies with BS EN 60670-22 which covers Junction boxes, but that is surely irrelevant, since that's a general standard which screw-terminal JBs also comply with.

I think you missed out some key words "in addition"

Whilst it could well be that the Ashely/Hager product actually is reliable enough to be inaccessible, I'm extremely sceptical as to whether use of them in non-accessible locations would be compliant with BS7671- what do others think?

Kind Regards, John.

I think if you are looking for a definitive standard you will be disapointed. However the regs do allow for new inventions; see 120.3 and 120.4. Hager have made what in my opinon is a good JB and issued a statement that satisfies me with regards to 526.3.