Flexible 'tails'

grahamro said:

1 strand out of 19 hardly counts as a whisker in my world.

it's over 5 % of the metal part of the cross-sectional area. However, with larger csa, given the skin effect, it may well represent sizeable amount of the actual conducting cross-sectional area at the point of entry to the terminal, especially as the dropped strand will be on the outside of the bunch !!

Luckily skin depth in copper is 8-9 mm at 50 Hz, so unless you've got lots of harmonics, at 35 sq mm the skin effect isn't too much of a problem.

I think the other Grahams point was  that unlike the superfine stranded stuff with 0.1mm cores or whatever this is still quite chunky - the chances of leaving a strand out and not realising in reality must be pretty small - comparable to cases where the meter changer forgets to tighten something - which is also very rare but not quite never. In terms of stress on the terminals, the  7 strand is quite wilful ;-)  It would be hard to imagine a terminal that holds 7 strands and fails to hold 19 - but for a maker not to have bothered to test it and say so , that I can easily believe.
M.

gkenyon said:

grahamro said:

1 strand out of 19 hardly counts as a whisker in my world.

it's over 5 % of the metal part of the cross-sectional area

Nearer to 1.5 mm² than 1.0 mm². You could make a whole circuit out of that!

Bit of confusion creeping in here
Mapj1 posted

I wonder if Eon are worried about a stray whisker short circuit problem, either real or imagined.

I replied

1 strand out of 19 hardly counts as a whisker in my world

By that I meant 1 strand out of 19 is way bigger than a whisker. I'm sure the whisker he refers to is in a multistrand flex which is not the sort of cable I was talking about.

To be honest I probably should have started the post with the heading 'Flexible tails'
All I can say is that if I rack up @ my local wholesalers and ask for 25mm2 Class 2 stranded circular conductors, I'm going to get some blank expressions..
Still doesn't explain e.ons policy oh and apparently they've ditched their 10 hour off peak tariff and are only offering a 7 hour off peak tariff but that's discussion for another day

Bit of confusion creeping in here
Mapj1 posted

I wonder if Eon are worried about a stray whisker short circuit problem, either real or imagined.

I replied

1 strand out of 19 hardly counts as a whisker in my world

By that I meant 1 strand out of 19 is way bigger than a whisker. I'm sure the whisker he refers to is in a multistrand flex which is not the sort of cable I was talking about.

To be honest I probably should have started the post with the heading 'Flexible tails'
All I can say is that if I rack up @ my local wholesalers and ask for 25mm2 Class 2 stranded circular conductors, I'm going to get some blank expressions..
Still doesn't explain e.ons policy oh and apparently they've ditched their 10 hour off peak tariff and are only offering a 7 hour off peak tariff but that's discussion for another day