Tight angles with 25mm Tails

[La Poste]

Greetings.
I have been working with 25mm tails today and had some tight angles to do.
I wonder does anyone have a preferred method for bending tails, sometimes with a tight angle it's not easy to use my hands and I am loath to used pliers on the insulation.
What sort of angle do you think is safe to bend the 25mm cable?
How tight is too tight?
Thanks alot.

 

[Darkwood]

Cables have a calculation that should be applied to work out you minimum bending radius, from you post i must make you aware you are not complying to regulations and will be in fact stretching the conductors on the outside of the bend you shouldnt need to even consider using tools to achieve a bend, there is no such thing as a tight bend in relation to the cable size and if you find yourself doing this then you have designed the installation wrong, i can only assume your trying to sweep the cables into the main switch from a vertical approach, not only does this exceed allowable bending radius but also can put unwanted force on the switch and sometimes pushing it out of its position.

 

[telectrix]

agreed. bend it round your knee. tight enough

 

[SirKit Breaker]

agreed. bend it round your knee. tight enough

I would have to have small knees to get 25mm tails into your average CU. My method is to bend it by hand about 6 inch longer than it needs to be, cut to length, prepare the end, then feed into CU meter end first, drop CU end into isolator and nip up, fit meter end, then fully tighten CU connection.

 

[telectrix]

6" longer. that's a lot of waste, as my missus would say.lol

 

[Darkwood]

Having said that i can understand its sometimes ok to be tight bends in consumer units and sometimes neccessary although you will exceed min bend radius its not such a issue as you would get will a long length of cable as the cores rather than stretch will retract from the end so one of the few occasions that i see you can deviate from the regs as you wont be damaging the cores by stretching them and under-mining the current carrying capacity. p.s. its just speculation and i never said any of the above.......

 

[chiplard]

To terminate into the main switch ( if coming from below ) I bend it round a large screwdriver once I've stripped the insulation. The individual cores slide over each other which leaves them at different lengths, then cut to make them equal length and terminate. No worse than the bend you get when terminating 4mm in a socket.

 

[SirKit Breaker]

Fully agree with not using tools though, I once badly damage a 25mm tails using pliers in my earlier days.

 

[Benny2]

agreed with chiplard somtimes you have no choice the screw driver is a good tool, especialy the cheaper boards can be tricky with the likes of clip on mcbs and rccbs, i have nt got much hair left to pull out so need to get it right 1st time nowadays lol.

 

[La Poste]

Ok thanks for your replies.
The reason I asked is because the system in question is a TT system.
There are two boards one below the other and a 100ma S type 100A time delayed RCD to cover everything.
The 25mm tails go into the top of the S type RCD and 25mm tails come out the bottom.
These exiting tails then go into a Henly block and split into two sets of 25mm tails one for each board.
In my effort to make it all nice and neat I am finding that the angles are getting very tight and it's starting to look ugly.
However, is there another way?
Could anyone recommend a 100A flexible cable that I could use.
The flexible cable will be completely enclosed in the plastic enclosures of the boards.
Would 16mm tri-rated cable be adequate for use inside the boards?
Does anyone have any suggestions or recommendations for a cable that is easier to work with than 25mm tail cable when trying to fit it in tight spaces inside consumer units?
As I said the cable will come out of the outgoing side of the 100 ma S type RCD and then go into two sets of 100A isolator switches to feed two boards.
Thanks alot.

 

[telectrix]

i have used Radox 16mm single cable (120A) before now. easy bend .as long as it's enclosed.

 

[AlanWirral]

When going into a main switch from the bottom i just bend them by hand! I strip it first leaving a bit of colour showing also. Then when it's bent i clip off the excess length off the copper due to the bending..if you get me..

 

[Spudnik]

I would have to have small knees to get 25mm tails into your average CU. My method is to bend it by hand about 6 inch longer than it needs to be, cut to length, prepare the end, then feed into CU meter end first, drop CU end into isolator and nip up, fit meter end, then fully tighten CU connection.

Exactly how i do it.

Nothing worse than trying to do it the other way round.

 

[Graeme Harrold]

As above I bend everything to shape first, trim the ends square, leaving about 10-15mm of colour too. Once the bends are in place will I then slot it all into place.

 

[Bigboy247]

I think MK might be another main stream manufacture, they do a tails adapter which is rigid with the bends at the top for connection into the isolator, at the bottom are the two holes for 25mm tails which just come out of the bottom of the board so your tails go straight to the bottom of the fuse board nice and neat with no bends in the tails as the enter the board.Just cant remember who made them, sorry.