Siemens SINAMICS SM150

The DC link capacitors smooth the voltage and stop the energy in the DC link. The DC link
capacitors are maintenance free and self-healing. The drive is switched off when the circuit-
breaker is disconnected. The DC link is discharged by means of balancing resistors.
3.5 Description of the components
3.5.1 SIMOTION Control Unit
The D455-2 DP Control Unit is the central control module for the closed-loop and open-loop
control of the converter. The connections are wired internally to the customer terminal block.
Further information is available in the following documents:
● You will find information on the wiring in the circuit manual in the "Technical specifications
and drawings" appendix.
● You can find information on the interfaces and LEDs in the "D4x5-2" document.
3.5.2 Terminal Modules
The Terminal Modules are the central interface for digital and analog inputs and outputs. You
can optionally expand the interface to include additional Terminal Modules.
Further information is available in the following documents:
● You will find information on the wiring in the circuit manual in the "Technical data and
drawings" appendix.
● Information is provided on the interfaces and LEDs in the "Supplementary component
descriptions" document on the CD.
See also
Technical data and drawings (Page 197)
3.5.3 Precharging
To prevent overcurrents and temporary overvoltages in the DC link when the line voltage is
connected, the DC-link capacitors must be precharged. The DC link is precharged via the
auxiliary supply.
The precharging circuit comprises the following components:
● Precharging transformer
● Diode bridge
Description
3.5 Description of the components
SINAMICS SM150 6SL3845-7NN46-7AA0
Operating Instructions 04/2017 35