ABB ACS800-67LC, Руководство по оборудованию

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Planning the electrical installation 59
Suitable power supply networks
Converter can be installed in TN-C-S and TN-S systems (most generally used in wind
turbine installations).

TN-C-S power supply network
In TN-C-S power supply network separate neutral and protective conductors are used.
The supply, however, uses a common conductor for both the neutral and the earth. This
combined earth and neutral system is called the protective and neutral conductor (PEN) or
the combined neutral and earth conductor (CNE). A system shown below is usually called
the protective multiple earth (PME) system.

TN-S power supply network
In TN-S power supply network earth terminal is connected by the supply protective
conductor (PE) back to the star point (neutral) of the secondary winding of the supply
transformer, which is also connected at that point to an earth electrode. The earth
conductor usually takes the form of the armour and sheath (if applicable) of the
underground supply cable. A system diagram is shown below.
Secondary of
supply transformer
ACS800-67LC
Customer terminals
L1 L2 L3 PE
L N
L1
PEN
L2
L3
Transformer
Secondary of
supply transformer
L1
N
L2
L3
PE
ACS800-67LC
L1 L2 L3 PE
Customer terminals
L N
Transformer