Siemens SINAMICS S120 Manual page 357

NOTICE
Damage to further loads due to overvoltage
Overvoltage from switched inducted loads (contactors, relays) can damage connected
loads.
• Install suitable overvoltage protection.
Note
Malfunction because 24 V supply voltage is too low
If the 24 V supply voltage falls short of the specified minimum value on a device in the
assembly, a malfunction can occur.
• Select an input voltage that is high enough for there to be sufficient voltage on the last
device. Do not exceed the maximum value for the supply voltage. If required, supply the
voltage to the assembly at various locations.
Note
A regulated DC power supply is required to operate motors with a built-in holding brake. The
power is supplied via the 24 V connection (Safe Brake Relay). The voltage tolerances of the
motor holding brakes (24 V ±10%) and the voltage drops of the connecting cables must be
taken into account.
The DC power supply should be set to 26 V. This ensures that the supply voltage for the
brake remains within the permissible range when the following conditions are fulfilled:
• Use of Siemens three-phase motors
• Use of Siemens MOTION-CONNECT power cables
• Motor cable lengths: max. 100 m
AC Drive
Manual, (GH6), 07/2016, 6SL3097-4AL00-0BP5
Cabinet design and EMC for components, Blocksize format
10.5 24 V DC Supply Voltage
357