carshalton
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Why can`t you use Zs - Ze to accurately determine the value of R1 and R2
Thanks
Thanks
for most circuits, yes. but not for circuits with a combi, shower etcZs-Zdb should be more realistic though.
So how do you explain Zs = Ze + (R1 + R2)Hi mate,Z is the 'impedance' of the conductors in an AC circuit and is reliant on a number of factors. (measured live)
R is the resistance of a conductor - (normally a DC measurement whilst circuit is dead)
If you google 'impedance' you will immediately realise the difference between the two.
It therefore stands to reason that if you take one 'impedance' (Ze) from another 'impedance' (Zs), your answer cannot possibly be a 'resistance' (R1+R2)
Your answer will be another Z or 'impedance' - the difference between Zs and Ze.
It is an allowable calculation as an approximation of Zs, if it isn't possible to measure the actual Zs.So how do you explain Zs = Ze + (R1 + R2)
R1 + R2, though, should be a measure of conductor resistance only so, if you add what I said, to what 'Andy' said earlier:"For circuits rated up to about 100 A, in which the line and cpc conductors are part of the same wiring system or immediatly adjacent to each other and not separated by ferrous material the ac impedance is not signficantly greater then the dc resistance" In such case R1+R2 is approximately equal to Z1+Z2 and the use of a test instrument supplying a dc test current will generally be sufficent"
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