Electrical connection
8.1 Permissible line system types
8.1
Permissible line system types
Permissible line system types and voltages
The following table shows the permissible line voltages of TN line supply systems for the
motors.
Table 8- 1
Permissible line supply
voltage
400 V
480 V
When using the SINAMICS S120 drive system, the motors are always approved for
operation on the following line supplies:
● TN line systems with grounded neutral point
● TT line systems with grounded neutral point
● IT line systems
When operated on IT line systems, a protective device should be provided that switches off
the drive system in the case of a ground fault.
In operation with a grounded external conductor, an isolating transformer with grounded
neutral (secondary side) must be connected between the line supply and the drive system.
This protects the winding insulation from excessive stress.
8.2
Motor circuit diagram
The circuit diagram of a stator looks like this:
Figure 8-1
156
Permissible line voltages of TN line supply systems, resulting DC link voltages and
converter output voltages
Resulting DC link voltage U
600 V (controlled)
528 V (uncontrolled)
634 V (uncontrolled)
Circuit diagram of a stator
Converter output voltage (rms value)
DC
U
a max
425 V (controlled)
380 V (uncontrolled)
460 V (uncontrolled)
Naturally cooled 1FW6 built-in torque motors
Configuration Manual, 07/2017, 6SN1197-0AE01-0BP3