Indeed, at least 'partially', but on needs at least two things connected gto the CPC to create any 'parallel paths'.
You're welcome
I worked it out from the 1mm² and 10mm² which looked more accurate at 44 and 4.4 respectively although obviously they both are likely rounded as well.
that it didn't matter what values were given for Volt-drop - or anything else - the ratio of the sizes is all that matters regarding the ratio of the resistances
So why did you imply that Jupiter might be wrong and that the value might be 1.61?
I haven't attempted to check the calculations but I think John has already explained his statement.
Did you not read my post?
Of course not - but 2.5:1.5 does.
As you say, that 'looking more accurate' is really just 'cosmetic', given that they are undoubtedly rounded - there's no reason to think that copper conveniently has a resistivity that results in a conductor having a 'nice round resistance' in the units we have chosen to use!
I agreed with that back in post # 11.
That 'implication' is in the eyes/mind of the reader - it was not intended.
Quite. Perhaps I was wrong to bother, but I was merely trying to anticipate some clever clogs jumping in and saying that the Bs 7671 VD figures resulted in a ratio other than 5:3.
...and even those figures you have quoted will be 'rounded (to one and two DP respectively - few, if any, things in nature have 'totally round' values (in the units we chose to use).
If by "disconnecting everything" you mean disconnecting all CPCs from the earth bar then, yes, that would eliminate the effects of any parallel paths which involved three or more circuits, but I doubt that would apply to many such paths.
One has to be aware, as I'm absolutely sure you are so this may be for the benefit of others, that the % error between 43.50 and 44.49 is smaller than 17.50 and 18.49. As such looking at the figures for larger size wire and calculating down should produce more accurate
I was merely agreeing with the error that you clearly explained exists in other parts of the documentation. However a very quick calculation with pencil so possibly not perfect, the extremities of the rounded figures: 12.1/7.41 do not reach 5/3 so it appears something is not right.
For a start, you seem to have got that back to front. Per BS 7671 figures, the 44 (with the smaller potential percentage error due to rounding) id that for 1 mm² cable, but the 18 figure (with the larger potential percentage error due to rounding) is for 2.5 mm² cable - so, for the comparison of 1 mm² and 2.5 mm² cables, the 'the more accurate' figure (the one with the smaller potential error due to rounding) would be expected to be the one for the smaller size of conductor (the opposite of what you suggest).
Yes, although the discrepancies are fairly small, it is hard to explain why, from any one source, the ratio of resistances for two different CSAs should not always be exactly the inverse of the ratios of the CSAs.
Yes you are absolutely correct, what happened was terrible editing, I corrected one part but not the other.
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