Siemens SIMOTICS S-1FT7 - Electrical Connection; Permissible Line System Types; Circuit Diagram of the Motor

S-1FT7 synchronous motors
Configuration Manual, 09/2018, A5E45099423B AA
367
Electrical connection
8
8.1
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.
8.2
Circuit diagram of the motor
1
Feeder cable
4
Encoder
2
Power Module
5
Brake
3
Motor
Figure 8-1 Circuit diagram