Line Contactors; Dc Supply Voltage; General - Siemens SINAMICS Series Equipment Manual

Cabinet Configuration and EMC Booksize
7.3 24 V DC supply voltage
7.2.4

Line contactors

Line contactors are required for electrical isolation of the drive line-up from the power supply
network.
For selection of the line contactor, the characteristic values in the technical specifications
apply. The cable routing, the bundling factor, and the factor for the ambient temperature
according to EN 60204-1 must be taken into account in rating the conductors to be
connected.
Caution
Line contactors must not be switched under load.
When the digital output is used to control the line contactor, the make/break capacity must
be taken into account.
You are advised to connect overvoltage limiters to the contactor coils to limit the opening
overvoltage. See catalog D21.2.
7.3 24 V DC supply voltage
7.3
7.3.1

General

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.
Notice
If other consumers are connected to the power supply, connected inductance devices
(contactors, relays) must be fitted with suitable overvoltage protection circuits.
7-6
Modules, as well as the process voltage of their digital inputs
Equipment Manuel for Booksize Power Modules
Manual, (GH2), Edition 06.2005, 6SL3097-2AC00-0BP2