UK Insulating copper tube splices

[John-]

Hi, what are people using to re insulate a copper through crimp In a metal adaptable box please? Also my SWA CT650H crimp tools don't want to crimp splices - E.g On the 10mm setting a good tug and the splice falls off, setting to 6mm will crimp nice and snug. But thats not great. Any guidance on this also please would be appreciated.

cheers

John

 

[Pete999]

Hi, what are people using to re insulate a copper through crimp In a metal adaptable box please? Also my SWA CT650H crimp tools don't want to crimp splices - E.g On the 10mm setting a good tug and the splice falls off, setting to 6mm will crimp nice and snug. But thats not great. Any guidance on this also please would be appreciated.

cheers

John

Several layers of a decent heat shrink, what do you use?

 

[James]

Several layers of a decent heat shrink, what do you use?

Heat shrink, gone are the days where a few layers of tape would be ok!

 

[DefyG]

Don't know about the crimping issue, perhaps try another brand of splice crimps?
Personally like Pete, several layers of heat shrink but have seen joints within short length of pvc conduit and also 'self amalgamating' tape used, which presumably becomes a solid insulation and not a tape!!!

 

[Flanders]

I rap a good layer of insulation tape round it the cover with heat shrink. Just remember to slide the heat shrink over one end of the cable before crimping it together

 

[telectrix]

Heat shrink, gone are the days where a few layers of tape would be ok!

since when ? red , black, or green. all available from local DIY store.

 

[R-fur]

Some people argue that tape does not comply with 416.1 as it can be unwound.

 

[John-]

I rap a good layer of insulation tape round it the cover with heat shrink. Just remember to slide the heat shrink over one end of the cable before crimping it together

Thats what i have done. I used some very thick clear stuff i got with a load of Robus LED strip. Not got much left. Do you have a link for the stuff you use please?

 

[Pretty Mouth]

Self amalgamating tape for me. Not as pretty as heatshrink, but one size fits all, and can be wound on afterwards

 

[John-]

Looks like this could be good:

View: https://www.amazon.co.uk/dp/B0742FJGFL/ref=cm_sw_r_cp_api_fab_LqIEFbK8WN1PB

 

[Lucien Nunes]

Yes, adhesive-lined 3:1 ratio is my preference too, e.g.
RS adhesive lined heat shrink
When properly fitted, products like this will provide insulation that is equivalent in durability and dielectric strength to the original cable insulation. Many basic heatshrink products have a thin wall and are much less durable.

With 3:1, choose a size about twice the diameter of the joint; this allows the tubing to shrink by 50% (which doubles the wall thickness) but leaves a margin of shrinkiness so that it grips firmly. On large joints especially, preheat the joint so that the adhesive doesn't cool and solidify too quickly when it makes contact. Once cooled and set, it should be difficult to peel off the joint even with a knife or cutters; like normal insulation you can hack into it but it stays stuck firmly in place.
[automerge]1601844860[/automerge]
Re the tool, I suspect a mismatch between dies and splices. Are they SWA branded|? A properly crimped splice should be completely impossible to remove in any way at all. Under tension the cable should stretch and snap, leaving the joint intact.

 

[John-]

Yes, adhesive-lined 3:1 ratio is my preference too, e.g.
RS adhesive lined heat shrink
When properly fitted, products like this will provide insulation that is equivalent in durability and dielectric strength to the original cable insulation. Many basic heatshrink products have a thin wall and are much less durable.

With 3:1, choose a size about twice the diameter of the joint; this allows the tubing to shrink by 50% (which doubles the wall thickness) but leaves a margin of shrinkiness so that it grips firmly. On large joints especially, preheat the joint so that the adhesive doesn't cool and solidify too quickly when it makes contact. Once cooled and set, it should be difficult to peel off the joint even with a knife or cutters; like normal insulation you can hack into it but it stays stuck firmly in place.
[automerge]1601844860[/automerge]
Re the tool, I suspect a mismatch between dies and splices. Are they SWA branded|? A properly crimped splice should be completely impossible to remove in any way at all. Under tension the cable should stretch and snap, leaving the joint intact.

Thank you for the detailed response. Re the crimps. No they are not. Naively i didn't appreciate you had to pair crimp and crimp tool... i guess I will be redoing a load of crimps now then...

 

[pc1966]

The SWA-brand lugs seems to be slightly thicker copper than many of the ones you get from other places so the hex-style of crimp is not quite enough. Maybe the dent-style of crimp tool is more forgiving:

Heavy Duty Semi Ratchet Crimping Tool

This versatile crimping tool combines a heavy-duty design with ratchet action to take on a wide variety of tough jobs. It has the capacity to crimp copper tube lugs and connectors from 1.5 to 16mm², with high compression pressure ensuring safe, consistent and precise crimping.• Ratchet-type...

www.toolstation.com

For covering then I too would choose the glue-lined heatshrink if available.

 

[Darkwood]

I suspect your crimper is a shaped crimper but would suggest you'd be better with an indent crimper for these types as they are more forgiving with brand variation, as Lucien points out, your probably getting a mismatch in suitability of the crimper and crimp brand which even if it feels tight may be a poor crimp and fail under load or fault condition.

The CT1095i is a indent crimper in the same range and this will be better if you source your crimps from various manufacturers, the ones you have enclose the crimp fully and rely heavily that the crimps are shaped and sized to suit the crimper to give a good joint.

 

[R-fur]

shrinkiness

shrinkiness, great word