Is this likely to be the theory underpinning the guidance for main bonding conductor resistance?
0.05 Ohm is what is considered ‘negligible resistance’. It could be 0.00 Ohm, but on the basis of a 5% tolerance for digital instrument accuracy, then a true value of 0.00 Ohm could display 0.05 Ohm on a test instrument.
So, 0.05 Ohm it is; nothing to do with Ohm’s Law or any other electrical principles just basically what a test instrument would be allowed to display when there is negligible resistance.
In practice this equates to approximately 27 metres of 10mm conductor for main equipotential bonding.
