I suppose that where the utility services are still metalic then main protective bonding would be required and where there is a chance of shock from a circuit fault or from a broken PME supply neutral (if it exists) then the supplememtary bonding is to guarattee that the fault voltage within the special location doesn't rise higher than a voltage that would be likely to kill or cause a serious injury.
I suppose that where the utility services are still metalic then main protective bonding would be required and where there is a chance of shock from a circuit fault or from a broken PME supply neutral (if it exists) then the supplememtary bonding is to guarattee that the fault voltage within the special location doesn't rise higher than a voltage that would be likely to kill or cause a serious injury.
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