Power Supply And Connection Of Components - Siemens SINAMICS S120 Combi User Manual

Cabinet design and EMC
13.6 24 V DC supply
Only motors with a safe electrically isolated holding brake may be connected. The brake
cores must also be safely electrically isolated.
If the motor power cable is connected to intermediate terminals, the power cables and
brake cables must be routed separately (≥ 300 mm).
Only safety extra-low voltages (DVC A) that comply with EN 61800-5-1 must be connected
to the connections and terminals with ratings of between 0 and 48 V DC.
Note
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 (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. 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:
• Use of Siemens three-phase motors
• Use of Siemens MOTION-CONNECT power cables
• Motor cable lengths, max. 50 m
NOTICE
If other consumers are connected to the power supply, connected inductance devices
(contactors, relays) must be fitted with suitable overvoltage protection circuits.
13.6.2 24 V power supply and connection of components
The S120 Combi with the expansion axes (Motor Modules) and DC link components are
connected to the 24 V DC via the integrated 24 V busbars. The current carrying capacity of
these busbars is 20 A.
The power can be supplied in two ways:
1. When using an external 24 V power supply, e.g. SITOP, the 24 V connector must be
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DANGER
DANGER
used. The external power supply should be located very close to the load (max. cable
length 10 m). Miniature circuit breakers with tripping characteristic D are recommended
as overcurrent. The ground potential M must be connected to the protective conductor
system (DVC A).
SINAMICS S120 Combi
Manual, Edition 07/2012, 6SL3097-4AV00-0BP3