Safety of multiple solid cores in one crimp

[Ardet R]

Just thinking as I complete a domestic EICR what the forum's thoughts are on the risks and levels of danger involved in multiple solid core cables being crimped into one end of a through crimp to use as a terminal block.

Obviously the crimp is not designed for this but will hold them together, how much worse than a screw terminal though?

Any movement will likely start to release the cores slightly and with say five cables could well not have caught one core at all, however I tended to think that it would be reasonably  likely to remain connected, but may have been infected by the views of multiple poor practices.

Certainly I am not sure it is an electrically and mechanically sound connection.

Thank you.

example stock picture:

 

[Tony S]

Only one way to find out. Crimp three cores and then gently cut through the joint.

 

[Murdoch]

Snip it off and replace with a wago....

 

[Ardet R]

Only one way to find out. Crimp three cores and then gently cut through the joint.

I think I know I will find gaps.

Snip it off and replace with a wago....

Simple answer and probably the easiest, not quite sure why the installer did not do this in the first place, it is only a lighting circuit.

 

[Murdoch]

Simple answer and probably the easiest, not quite sure why the installer did not do this in the first place, it is only a lighting circuit.

There are installers out there who don't know about or carry wago's ................... normally over 60!

 

[Tony S]

There are installers out there who don't know about or carry wago's ................... normally over 60!

Oi, I resent that comment! Don’t tar all retirees with the same brush  msl1:

 

[roys]

Well I'm retired  but I must admit I think Wagos are great and use them on family and friends jobs.

As to the crimping of single solid drawn, don't know if it was an industry spark  think but we would never crimp a single solid drawn wire.

As for Ardets OP I would be cutting that of and putting a Wago on as mentioned by Murdoch

 

[binky]

I have tried such things in the past and it is difficult to get a good grip on to multiple cables, but assuming that has been achieved, then I'm not sure I would consider it a problem?

 

[Tony S]

Three 1.5mm² in to a 6mm crimp should be doable so long as the conductors reach the centre of the barrel.

 

[Ardet R]

I think the jury is out on the use of crimps on solid cores in normal use, some say never ever do it and some say it is OK.  I note the instructions on the crimps never mention solid core either positively or negatively, but if the crimp is soundly made  and distorts the core then it should be OK but not as effective at holding as on stranded conductors.

These crimps seemed solid but I did not risk pulling too hard or I may have had to do the repair during the inspection and I was already pushed for time.  They were being used for neutral connections on fed light switches and also for the cpcs in some cases.  6mm crimps for three cores and 2.5mm crimps for two cores on 1mm² T&E.

Thank you for the thoughts, I have put it down as improvement recommended in this case.

 

[Andy™]

I think the jury is out on the use of crimps on solid cores in normal use, some say never ever do it and some say it is OK. 

imo, no issue with solid core on uninsulated crimps. insulated crimps do work but they are not as strong as uninsulated. pic from a few years ago pulling uninsulated crimps apart with stranded & solid

 

[Tony S]

Something to bare in mind, the insulated crimps come from the automotive industry they were never designed for solid conductors.

 

[kerching]

There are installers out there who don't know about or carry wago's ................... normally over 60!

How very dare you!

..written by the FIRST PERSON IN THE ENTIRE WORLD to purchase a grey and a clear WAGO cannister box and all the associated brackets, clips, earth straps etc

and yes I am the wrong side of 60

just saying :slap  

 

[Ardet R]

imo, no issue with solid core on uninsulated crimps. insulated crimps do work but they are not as strong as uninsulated. pic from a few years ago pulling uninsulated crimps apart with stranded & solid

That is useful to see, the deformation of the core gives you hope for security of contact.

As you say the insulated ones are weaker, but if the crimp force is similar it should also deform the core (but would it stay)?

I crimp solid cores anyway, they seem OK in most cases.  I just do not do multiples into one crimp; though I do with bootlace ferrules, but different application and requirements.

 

[Sidewinder]

Crimps on solid are "ok" as long as they are stationary and not subject to vibration or movement I suppose, not my favourite thing, but they do work, ish.

Multiples, I would really not be keen on, and I doubt that the crimp quality would be correct, because the "filler" in the crimp, the wire,  would not be the csa to match the crimp die.

Multiples in bootlaces, ok, as long as you use the double bootlaces, otherwise one wire end, one crimp.

Certainly not 3 or 4 in one bootlace, and if it's machinery never any multiple protective conductors in one crimp, for protective conductors, always one crimp one wire end.

It's also a non-compliance with the standards for machinery to put multiple protective conductors in the same terminal, and would thus for new machinery where the OEM is using EN's to claim a presumption of conformity it would be against the law, and technically a fraudulent claim on the documentation.

IF, it's a modification to a machine then the WED requires compliance with the same standards as the MD, so same case.

 

[roys]

Sidey what does WED stand for, if I once knew I have forgotten.

 

[kerching]

Working Equipment Directive?

just wildly stabbing in the dark

 

[roys]

Ahh makes sense. I remember having to sign out of the Working Time Directive so that I could get worked for loads of hours.