Crimps in consumer unit?

[SparkyJoe]

Well it seems ive been doing it wrong for the past 10 years, along with loads of other people ive worked with. as ive always used crimps on solid core cables.

 

[Spark1979]

Well it seems ive been doing it wrong for the past 10 years, along with loads of other people ive worked with. as ive always used crimps on solid core cables.

Me too, oops! Always thought crimps were for solid cables too always give them a good tug and to my knowledge never seen a burnt out crimp, but I have been proven wrong many times - mostly by the wife though

 

[supertoad]

i thought solid core was ok in crimps also

 

[Darkwood]

Solid core crimping in banned in most industries like rail, NASA, Aviation etc etc but stranded or allowed it kind of spells it out for you as its been proven time and time again to be an unreliable crimping method...

And here's the reason... when you crimp a stranded cable with correct ratchet crimper it shapes the crimp in a manor that it holds its structural integrity and give good surface area contact, with stranded this is easily achieved as the crimping action shapes the strands into a tight formation and because they are loose they adapt to the crimp shape.
Now a solid core doesn't mold into the crimp shape and create a situe where the crimp deforms around it which can't guarantee the crimps structural integrity and also surface contact can sometimes be at two points only the top and the bottom with pockets around the core.
The final issue is flexing of cables if a standed cable is moved and wiggled all the energy is absorbed in the flexing of the strands where-as solid core tranmits a large percentage of the energy into the crimp joint where it becomes prone to loosening even after just a few occasions as this is also coupled with a deformed crimp joint.

 

[KAS1]

I think anyone who's been involved in any major industrial electrical contracts would know this about crimps, but people who have spent all their working lives on house bashing wouldn't lol

 

[KAS1]

Just shows even after 10 years people are still learning, nobody knows it all that's what we're all here for to share things we know

 

[Octopus]

Back to the OP, what load is there going to be on the new sockets? If its small I'd do a spur from the CU to a FCU, then to the sockets. Far better IMHO

 

[KAS1]

Back to the OP, what load is there going to be on the new sockets? If its small I'd do a spur from the CU to a FCU, then to the sockets. Far better IMHO

I like this answer as well , I bet you wouldn't of even asked the question.

 

[amlu]

crimped lots of cables on house bashing, never had any problem, good ratchet crimper and insulated blue crimps do the job for 2.5 cable. its not nasa, those cables wont fly to space.
you can stick them in some wago too.

 

[KAS1]

Where would you use crimps house bashing?

crimped lots of cables on house bashing, never had any problem, good ratchet crimper and insulated blue crimps do the job for 2.5 cable. its not nasa, those cables wont fly to space.
you can stick them in some wago too.

 

[Jdsparky]

Take one leg out and put to a socket next to consumer unit then on to other sockets then return to cu if you don't want any joints, be it crimps, connector blocks or other methods....nice easy test point aswell for Rcd tripping times in future cus that's all it would get used for lol

 

[sparkless]

always crimps, never knew about the solid core thing tho,
'spose I'll never get that job at NASA now

 

[Engineer54]

How many people on here would crimp a lug on a piece of MICC ?

ME, and have terminated MICC cores far more time's than i care to remember using crimped terminations!!

 

[Engineer54]

Never had the problems that have been mentioned above, crimping solid core cables. The only bad crimps i've seen using a good crimping tool and good crimps, have been down to operator error!!
Though i don't like the PVC insulated crimps, i prefer the heat shrink type, and better still bare crimps, with heat shrink tube covering!!

 

[vaughant]

What's wrong with solder and heat shrink?
Would be as good as the original then?

 

[timbobelfast]

Where would you use crimps house bashing?

Only place I would use crimps and lugs when hoose bashing would be on the bonding conductors or at the rod if its a TT

 

[telectrix]

and on fly leads when using SWA!.

 

[kingeri]

Where would you use crimps house bashing?

I don't understand that question. Anywhere where you'd need to make a sound connection....

 

[Engineer54]

On virtually every project i've been involved with, on final distribution boards every termination into protective devices, relays, contactors and the like within those distribution boards have ALL been crimped terminations of one type or another!!

As far as i've seen, rail signaling cables and the like are basically all stranded cables anyway, as are cabling and wiring on the trains themselves, The same as your typical car, stranded wiring is used throughout for obvious reasons. Your typical electrical installation isn't subject to continuous vibration or anything like it, so why try and impose rules based on criteria that it won't be subject too!!


As for the wiggling free thing, you can say exactly the same thing about every screwed wire/cable connection ever made, ...So do we ban these now??


Let commonsense rule for a change!! lol!!

 

[Darkwood]

I see your reasoning E54 but consider a bunch crimps within a consumer unit YES! untouched and no vibration they may well serve there purpose but any following spark who makes additions, test or alterations and moves the cables cannot know or guarantee the integrity of the original joint hasnt been compromised simple saying it isnt subject to continuous vibration or anything is a poor argument to justify what amongst many industries has been deemed to be bad practice and a unreliable jointing method (refering to solid core crimping using standard ratchet and crimps).
Just because you may not of had or experienced any issues with this method does not justify it in a debate, all cable connection methods used throughout any industry has been scrutinised tested and examined to determine whether acceptable and crimping with standard ratchet and using standard crimps fails the test because of the reasons in my previous post -the solid core keeps shape while the crimp deforms around it which is not how the manufacturers designed it.. the crimp needs to take the shape its designed to do and the cable needs to mould to this crimp shape which isnt an issue when cores are stranded.

The reason why its a grey area in our industry is its been accepted that this isnt a wide spread practice as those who crimp often know it shouldn't be done and many alternatives exist, its just the case that your average domestic sparky tools up with a crimper and thinks its versatile and usable for all types of cable which had they done their research they will find it is not.

I was taught at college about the various crimping methods and tools we were shown blown up images of incorrect crimping methods and why and one showed a solid core and the crimp itself had fracture lines and contact free pockets around the core meaning surface area contact was minimal, i see often those argue against me saying they never had an isssue etc etc but with no other backing of the argument... if you want il try digging out my 25yr old college papers and forward the pics

Just an Edit to re-iterate we are discussing using the standard ratchet crimp and standard crimps here other forms of crimp are acceptabe on solid and are so designed i.e. data cables, telephone crimps etc