Siemens SINAMICS S120 Equipment Manual page 22

Introduction
1.7 Additional information
Ground symbols
Table 1- 1
Testing the protection against electric shock when using frequency converters
Protection on indirect contact in the motor circuit of a converter and automatic disconnection
in case of a fault in accordance with DIN EN 60364-4-4 VDE 0100, part 410 is ensured if the
following conditions are met:
● The installation instructions provided in the documentation of the converter have been
followed, in particular, regarding
– Equipotential bonding
– Conductor cross section
– Fuse protection
● The valid standards were complied with during installation:
– DIN EN 50178 VDE 0160
– DIN EN 60204-1 VDE 0113, part 1
– DIN EN 60364-5-52 VDE 0100-520
– DIN EN 60364-5-54 VDE 0100-540
● Continuity of the PE conductor is ensured according to DIN VDE 0100-600 (IEC 60364-6)
Converters of the SINAMICS series meet the requirements defined in DIN EN 60364-4-41
VDE 0100, part 410 and comply with the specified break times.
Background
In the case of a short-circuit with negligible impedance to ground, the converter interrupts the
circuit within the shortest time (<< 100 ms). As a consequence, there is very high impedance
between the converter DC link and the output (> 1 MΩ) so that the possible voltage as result
of the voltage divider with the impedance of the ground connection between the motor and
converter is less than 50 VAC or 120 VDC.
20
Symbols
Icon Meaning
Connection for protective conductor
Ground (e.g. M 24 V)
Connection for function potential bonding
Manual, 06/2019, 6SL3097-5AL00-0BP1
AC Drive