Dc Supply Voltage; General Information - Siemens SINAMICS S120 Equipment Manual

9.3 24 V DC supply voltage
9.3
9.3.1

General information

The 24 V DC voltage is required for the power supply of:
1. The electronics of the SINAMICS components via the integrated 24 V busbar
2. The electronics of the Control Units, Option Boards, Sensor Modules, and Terminal
3. The load voltage of the digital outputs
4. The motor holding brakes
Other loads can be connected to these power supply units if they are separately protected
from overcurrent.
Note
The electronic power supply has to be supplied by the user as described in the System Data
chapter of this documentation.
When connecting a DC power supply as specified in EN 60204-1:1997, sect. 4.3.3,
malfunctions may occur due to the voltage interruptions permitted for them.
NOTICE
If other consumers are connected to the power supply, connected inductance devices
(contactors, relays) must be fitted with suitable overvoltage protection circuits.
NOTICE
A regulated DC power supply is required to operate motors with a built-in holding brake.
The voltage is supplied via the internal 24 V busbars. The voltage tolerances of the motor
holding brakes and the voltage drops of the connection cables must be taken into account.
The DC power supply should be set to 26 V. The Control Supply Module supplies 26 V.
This ensures that the supply voltage for the brake remains within the permissible range
when the following conditions are fulfilled:
• Using Siemens three-phase motors
• Using Siemens MOTION-CONNECT power cables
• Motor cable lengths: max. 100 m
Booksize power units
Manual, (GH2), 06/2008, 6SL3097-2AC00-0BP6
Modules, as well as the process voltage of their digital inputs
Cabinet Design and EMC Booksize
9.3 24 V DC supply voltage
501