Specifications

17
Schneider Electric
Review (continued)
Power system earthing arrangements
TT system
Note that overvoltages may be caused by separate earth electrodes for which the
potentials vary differently.
TN-C system
If the distribution system is TN-C, it is highly recommended to adopt a TN-S system
right from the building entry point.
The various power system earthing
arrangements are equivalent for the safety
of persons and have little effect in relation
to EMC.
Certain features of the different
arrangements must nevertheless be taken
into account.
E52281
Shielding connected
at both ends
Loop capable
of capturing
radiated fields
Flow of high
disturbing currents
Shielding connected
at both ends
PEN
Cabling Guidelines