Siemens SINAMICS SM150 - Voltage Sensing Module; SMC30 Sensor Module; Precharging

3.5.4 Voltage Sensing Module
The Voltage Sensing Module VSM10 measures the actual line voltage values for the Active
Line Module.
3.5.5 SMC30 Sensor Module
The SMC30 (Sensor Module Cabinet-Mounted 30) evaluates motor encoder signals. The
sensor module transfers the speed and actual position value to the Control Unit via the internal
DRIVE-CLiQ communication interface.
Note
If an encoder fails, the mode can be switched over to "encoderless".
3.5.6 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
● Precharging resistors
● Contactor for switching on and off
● Circuit-breaker
Detailed information about interconnecting the precharging components is provided in the
circuit manual. The component mounting locations are provided in the layout diagram.
Designation Value
Precharging time
1)
25 s
Precharging current in three-phase 400 V supply 20 A
Discharging time of the DC link T
DISCH
1)
≈ 25 min.
1)
The time can vary depending on the system
Description
3.5 Description of the components
SINAMICS SM150 6SL3845-7NN46-7AA2
36 Operating Instructions Rev.201910281345 EXAMPLE