Permissible Line System Types - Siemens SIMOTICS S-1FK2 Operating Instructions Manual

Connecting

6.2 Permissible line system types

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.
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SIMOTICS S-1FK2 synchronous motors for SINAMICS S120
Operating Instructions, 02/2022, A5E46089564B AD