Compliant junction boxes

[anniesdad]

Hi all, (Chris) i’ve put the down lighters in the soffits and they look pretty good if I do say so myself.

Can I ask if all junction boxes are considered compliant as long as they clamp the outer cable securely? I’ve used standard screw up connectors (the ones you get in strips) to join the conductors at each light. This connector is held within a rigidplastic box that has screw up clamps gripping the outer cables. They are not fixed but accessible by popping out the downlighter, reaching in and pulling out. Would these JBs also be suitable for unaccessable locations like the ceiling void? Im not really sure what a maintenance free connector is? Is a standard ceiling rose still compliant because this has no clamp for the flex / cables?

Thanks in advance

[csearle]

Hi all, (Chris) i’ve put the down lighters in the soffits and they look pretty good if I do say so myself.

Can I ask if all junction boxes are considered compliant as long as they clamp the outer cable securely? I’ve used standard screw up connectors (the ones you get in strips) to join the conductors at each light. This connector is held within a rigidplastic box that has screw up clamps gripping the outer cables. They are not fixed but accessible by popping out the downlighter, reaching in and pulling out. Would these JBs also be suitable for unaccessable locations like the ceiling void? Im not really sure what a maintenance free connector is? Is a standard ceiling rose still compliant because this has no clamp for the flex / cables?

Hiya, good job.

Yes cables should be supported or restrained at the entrance to junction boxes and enclosures.

Connectors are fine in accessible locations but not in inaccessible locations because the grub screws can work loose as, over time, the ductility of copper reduces the springiness with which it reacts to the pressure of the screws. Extraneous vibrations and those induced by the effect of alternating current flowing through a magnetic field can help screws work loose too.

Maintenance-free connectors have no requirement for periodic adjustment (e.g tightening of grub screws). They are usually sprung-loaded push-fit or lever connectors. There are many respected people, some here in this forum, that are skeptical about the longevity of such connectors.

A ceiling rose usually has a restraint on the flex, either because the cores are routed through S-bends to hold them or by having a distorted plastic washer around the flex to prevent it moving back through the exit-hole. The cable entries have no restraints so perhaps there is an argument for requiring clips to prevent movement if a cable is tugged. Ceiling roses are a funny one because the cross sectional area of the live conductors reduces without a corresponding increase in sensitivity of the over-current protection. An abomination. Mind you on the European continent they find it safe enough to have no fuses in their plugs to protect any of their flexes.

Regards,
Chris

[JMN2]

I read somewhere that 80% of new houses in Germany and USA are wired with Wago connectors, this German brand has junction boxes too. I used them in my one project and found them handy.

[anniesdad]

Thank you. These wago connectors and boxes are great. Really quick. I'm using the 222 lever connectors which will take 2.5ml cables in each entry. I've found that I can get 2 X 1mm cable in each entry and they're nice and secure and work well. Do you know if this is frowned upon?

[csearle]

Thank you. These wago connectors and boxes are great. Really quick. I'm using the 222 lever connectors which will take 2.5ml cables in each entry. I've found that I can get 2 X 1mm cable in each entry and they're nice and secure and work well. Do you know if this is frowned upon?

Well, as I said earlier, some are skeptical, but I often work together with other electricians hereabouts and we have all pretty much been obliged to move over to Wago or Ideal connectors. There is no doubt that they are quick, useful, and re-useable. The doubters ask what state they will be in in 20 to 40 year's time.

Regards,
Chris
PS To your point: I would not put more than one wire in each entry because a) that is probably not what the manufacturer intended, and b) there is I believe a danger that the spring might make a better contact with one wire than the other, which might lead to corrosion and over-heating of the less-well-made junction.

[anniesdad]

Ok thank you One wire per hole it is. Just bought these newer wago 221s which take 5 wires, they seem even better, more compact and its so great not having to screw in to clamp conductors from awkward angles. Yes I too wonder what they will be like in 20 years time. I’ve taken photos of where the junction boxes are but they just about to be covered with 150 ml celotex and plastering