Why do people twist CPC's?

Graham The Spark: 
 

The latest video from “Doctor Electric” on YouTube has really annoyed me(titled "Best ZS Ever)!

What is it with these YouTube “Sparks” that they think they can just start up a channel and think they're god?

On this video Doctor Electric shows viewers how to twist the CPC's to get a better ZS!! UNBELIEVEABLE!!!

https://www.youtube.com/watch?v=448_LH9GKDo

Using the drill to twist C.P.C.s together tightly looks like a good way to damage them. I may just twist together the ends of C.P.C.s for a cm or so to provide a good reliable connection in a socket terminal, but I would never use a drill and twist the whole length. Also, if somebody wants to test for ring continuity at a socket untwisting the C.P.C. is very difficult.

I don't like C.P.C.s bring just pushed singly into socket earth terminals as they may not be reliably gripped. One may be only loosely gripped.

Z.

You will create a lot of interest if you post this item on the I.E.T's B.S. 7671 Wiring and Regulations' Forum I am sure,

Z.

Back in the olden days, before even my time, it was usual to twist  the shielded  CPCs of T&E outside the junction box with no other form of connection other than the odd blob of solder occasionally, often on top of the box it so it became impossible to open the box without the CPCs being untwisted. Of course it was quite common for lighting circuits not to have a CPC. Then in the 60's it was considered good practice to gently twist the CPCs so that if the screw came loose in the connector you still had a good connection to earth. This was before we inspected everything to death and a test of ring continuity at the main board and a global IR test and you were good to go live plus a test for polarity if you were conscientious. A figure of eight was a knot not a test. Since then I have snapped any number of twisted CPCs  while trying to undo them to modify, fault find  or test circuits. Usually when they have been twisted back to the point of entry into an enclosure you know the break is going to occur where it enters so it is almost impossible to make a joint. If they have been twisted with a drill the chance of snapping is very high. Of course when they have been twisted they will al have been stuffed into one piece of green sleeving which is impossible to get off and it is impossible to get the twisted shape of the single wire into the G/Y sleeve you have with you and when you try to straighten it,  it snaps.
I agree with Z about the problem of putting multiple singe wires into a connector but a tug test on each one should find the loose one or two and then you can spend a happy hour or two trying to get them all in a configuration which allows the screw or cage clamp to grip on them all. A little twist at the end does solve this even though you know future electricians will probably curse you.

It's quiet in here isn't it, one could nod off quite easily.

kfh: 
 

 

It's quiet in here isn't it, one could nod off quite easily.

It is not as quiet here as Netherworld whence this post originated.

I remember seeing the twisted earths (earth continuity conductors) above junction boxes when I was younger. No screwed terminal or even a Scruit, just twists of conductor. I thought nothing of it at the time and considered it normal. Even the 3 core or 7 core tinned copper stranded earth wires were just twisted outside a junction box. That was probably accepted practice in the 40s, 50s and 60s.

Z.

Although I am famous to a twisting aversion I will admit to twisting cpcs on switchboxes for the last few mm for the reasons stated, Sometimes I double em. I never twist a long length and never never never the whole length then sleeve it. I always ensure plenty straight left to remake a couple of times. A drill! dog forbid! What does he use to remove sheathing, an axe?

That made me wince. Thankfully, the barbarism was at the beginning so I didn't have to watch it through.

The biggest problem with that sort of video is that people will copy him.

Why do people twist cpc's?

With A TOCD to BS EN 60998-4, you have no choice.

gkenyon: 
 

Why do people twist cpc's?

With A TOCD to BS EN 60998-4, you have no choice.

I am at a loss to see the connection with Bufonidae?

Z.

gkenyon: 
 

Why do people twist cpc's?

With A TOCD to BS EN 60998-4, you have no choice.

Unfamiliar with the acronym or initials I did an Internet search:

”TOCD usually manifests as pure compulsions and rituals and does not have the fear element that something bad will happen if the ritual isn't completed.

These rituals are preceded by a physical sensation rather than an anxiety based thought.”

https://www.tictocktherapy.co.uk/post/the-difference-between-ocd-and-tourettetic-ocd-tocd

Regards the video, I couldn’t face watching all of it so I skipped through to the highlights, first they show you how to test ring continuity at a socket, then how to to twist the CPC’s together making it impossible to do what they just demonstrated. 

Graham The Spark: 
On this video Doctor Electric shows viewers how to twist the CPC's to get a better ZS!! UNBELIEVEABLE!!!

Probably arises from the standard practice In days of yore to increase conductor contact, and before the need to unravel twisted conductors before EICR's etc. Yeugh!

Jaymack