C1 Water pipe, metal from outside
C2 Waste water pipe, metal from outside
C3 Gas pipe with insulating insert, metal from outside
C4 Air-conditioning
C5 Heating system
C6 Water pipe, metal e.g. in a bathroom
C7 Waste water pipe, metal e.g. in a bathroom
D Insulating insert
MDB Main distribution board
DB Distribution board
MET Main earthing terminal
SEBT Supplementary equipotential bonding terminal
T1 Concrete-embedded foundation earth electrode or soil-embedded foundation earth electrode
T2 Earth electrode for LPS if necessary
LPS Lightning protection system (if any)
PE PE terminal(s) in the distribution board
E/PEN PE/PEN terminal(s) in the main distribution board
M Exposed-conductive-part
1 Protective earthing conductor (PE)
1a Protective conductor, or PEN conductor, if any, from supplying network
2 Protective bonding conductor for connection to the main earthing terminal
3 Protective bonding conductor for supplementary bonding
4 Down conductor of a lightning protection system (LPS) if any
5 Earthing conductor
IEC60364-5-54原文是:
543.4.3 If, from any point of the installation, the neutral/mid-point/line and protective functions are provided by separate conductors, it is not permitted to connect the neutral/mid-point/line conductor to any other earthed part of the installation. However, it is permitted to form more than one neutral/mid-point/line conductor and more than one protective conductor from the PEN, PEL or PEM conductor respectively.
The PEN, PEL or PEM conductor shall be connected to the terminal or bar intended for the
protective conductors (see Figure 54.1a), unless there is a specific terminal or bar intended for the connection of the PEN, PEL or PEM conductor (examples are given in Figures 54.1b and 54.1c).