All boils down to the accepted definition of extraneous conductive part
Seems to be a grey area
Seems to be a grey area
Has no one noticed the error on the OP's picture,
sure he's an electrician,
sure he can make pictures,
sure he cant get work as he cant explain bonding to customers,
sure he doesn't even know which side of the gas meter and water stop tap to bond to !!!!!!!!!!!!!
(Bonding is on the wrong side of gas meter at the moment)
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a subtle point but, yeah you could show the shock potential from the services at different voltages.
I guess the the key, stripped down point is that any metal coming into your house has the possibility of being at a different voltage to another piece of metal entering your house, by linking them together that possibility stops.??
I may be showing my ignorance here but..
If you touch a live object you will get a shock
If you touch a live object with one hand and some earthy metal with the other you may get a bigger shock as the fault path is better, and it will go across the chest.
The CPC is there to take a fault current to the protective device and clear the danger
fineThe bonding is there to create an equipotential zone so metals do not have different voltages
But...
Say you have bonding but the CPC fails The metalwork throughout the house (That is connected) will rise to the same potential as the faulty item via the bonding. Thus no potential difference will exist between the metal work so you will not get a shock.
But because their is no fuse to clear, the fault it will remain.
If for some reason some earthy metal entered the house, when touch you would get a shock.
Am I right in saying that an extraneous conductive part is something metal that comes in to the premises from outside the equipotential zone (ie a water supply pipe) and thus may not be at the same potential as the MET. But an extraneous conductive part is NOT just something metal inside the premises that could become live due to a fault (such as central heating pipes), these are called exposed conductive parts?
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