Connecting
6.2 Permissible line system types
SIMOTICS S-1FT2 synchronous motors for SINAMICS S120
58
Operating Instructions, 07/2021, A5E50610821B AB
6.2
Permissible line system types
In combination with the drive system, the motors are generally approved for operation on TN
and TT systems with
grounded neutral
and on IT systems.
In operation on IT systems, the occurrence of a first fault between an active part and ground
must be signaled by a monitoring device. According to IEC 60364-4-41, it is recommended
that the first fault is removed as quickly as is practically possible.
In systems with a
grounded external conductor
, an isolating transformer with grounded
neutral (secondary side) must be connected between the line supply and the drive system to
protect the motor insulation from excessive stress. The majority of TT systems have a
grounded external conductor, so in this case an isolating transformer must be used.
6.3
System integration
6.3.1
Connection notes
6.3.1.1
Motor connection
NOTICE
Destruction of the motor if it is directly connected to the three-phase line supply
The motor will be destroyed if it is directly connected to the three-phase line supply.
•
Only operate the motors with the appropriately configured converters.
NOTICE
Damage to electronic components as a result of electrostatic discharge
Electrostatically sensitive devices (ESD) can be damaged or destroyed by electrostatic
discharge.
•
Observe the ESD protection measures.
•
Only grounded personnel with grounded tools may touch the component connections.
•
Heed the EMC information provided by the manufacturer of the converter.
•
The manufacturer of the plant/machine is responsible for the ensuring that the installation
is performed correctly.
•
Observe the data on the rating plate and the circuit diagrams.
•
Adapt the connecting cables to the type of use and the voltages and currents that occur.
•
Use prefabricated cables from SIEMENS (not in the scope of delivery). These cables reduce
installation costs and increase operational reliability.
•
Make sure that the inside of the connector is clean and free of cable cuttings and
moisture.
•
Check that the degree of protection is complied with at the seals and sealing surfaces of
the connectors.
•
Secure connecting cables against torsion, tensile and compressive strain, and protect
them against kinking. It is not permissible to subject the connector to continuous force.
