Can someone let me know the science behind this please. I’ve been told that if there is a fault on a circuit the ZS values in the regs are there to give ADS in a time that is not going to cause considerable harm. My question is if disconnecting times don’t comply what is the dangers that arise I know it’s physics but have seen marshalling bars carrying current through earthing conductors all day and we don’t get a shock of them. Thank you for you help in advance guys just want to clear up some unanswered questions.
" I know it’s physics but have seen marshalling bars carrying current through earthing conductors all day and we don’t get a shock of them."
As long as the CPC/earthing conductors are properly connected then if you touch the conductors you will become a parallel resistance at the same voltage with a body resistance anywhere up to 1000+ times higher than the conductor path and will not experience a shock current.
If however, the earthing conductors are at a different voltage to the ground you are standing on then when you make contact you may experience a tingle. PME earthing systems present this problem.
" I know it’s physics but have seen marshalling bars carrying current through earthing conductors all day and we don’t get a shock of them."
As long as the CPC/earthing conductors are properly connected then if you touch the conductors you will become a parallel resistance at the same voltage with a body resistance anywhere up to 1000+ times higher than the conductor path and will not experience a shock current.
If however, the earthing conductors are at a different voltage to the ground you are standing on then when you make contact you may experience a tingle. PME earthing systems present this problem.
