Neutral - Earth Link in Main Switchboard

The use of initials like CPC confuse me as the live phase wire is [L] not [P] and earth[E]

The regs are written in a "living language".. (i.e. it keeps changing). At the moment..


Brown wires are "line" (hence L is OK again).

Blue wires are neutral (N)

Green/yellow ones are protective conductors - often either protective bonding conductors or protective earth (PE or earthing symbol). Protective conductors associated with a particular circuit are circuit protective conductors (and in some system - e.g. separated systems supplying more than one item - aren't actually earthed at all).


Combined neutral and earth conductors are PEN (Protective Earth and Neutral) (or sometimes referred to as CNE - Combined Neutral Earth - especially by those who doubt the safety of that approach and so like to deliberately omit any reference to "protective" in that context!)


The term "live" now means any Line or Neutral conductor - i.e. the normal current carrying conductors in normal service (but not a PEN, and ignoring protective conductor currents).


Mike's already described the different system for describing how an earthed system is arranged (which doesn't apply to non-earthed systems, of course, even when they have green/yellow protective conductors)


   - Andy.

The use of initials like CPC confuse me as the live phase wire is [L] not [P] and earth[E]

The regs are written in a "living language".. (i.e. it keeps changing). At the moment..


Brown wires are "line" (hence L is OK again).

Blue wires are neutral (N)

Green/yellow ones are protective conductors - often either protective bonding conductors or protective earth (PE or earthing symbol). Protective conductors associated with a particular circuit are circuit protective conductors (and in some system - e.g. separated systems supplying more than one item - aren't actually earthed at all).


Combined neutral and earth conductors are PEN (Protective Earth and Neutral) (or sometimes referred to as CNE - Combined Neutral Earth - especially by those who doubt the safety of that approach and so like to deliberately omit any reference to "protective" in that context!)


The term "live" now means any Line or Neutral conductor - i.e. the normal current carrying conductors in normal service (but not a PEN, and ignoring protective conductor currents).


Mike's already described the different system for describing how an earthed system is arranged (which doesn't apply to non-earthed systems, of course, even when they have green/yellow protective conductors)


   - Andy.