Dc Supply Voltage; General - Siemens SINAMICS S120 Equipment Manual

Cabinet design and EMC for components, Blocksize format
11.5 24 V DC Supply Voltage
Avoid, where possible, routing non-shielded cables, connected to the drive line-up, in the
immediate vicinity of noise sources, e.g. transformers. Signal cables (shielded and
unshielded) connected to the drive line-up must be laid at a great distance from strong
external magnetic sources (e.g. transformers, line reactors). In both cases, a distance of ≥
300 mm is usually sufficient.
Routing 24 V cables
When routing 24 V cables, the following must also be observed:
● No more than 1 conductor pair may be bundled together.
● 24 V conductors must be routed separately from other cables and conductors that could
conduct the operating current.
● 24 V cables must never be routed parallel to power cables.
● 24 V cables as well as power cables should be routed to the components so that they
never cover ventilation slots
Conditions of use for 24 V cables
● Ambient temperature 55 °C
● Limit conductor temperature, ≤ 70° C for operation with the rated load current
● Cable length up to 30 m for 24-V power supply cables or for signal cables without
additional circuit elements
11.5 24 V DC Supply Voltage
11.5.1

General

The 24 VDC voltage is required for the power supply:
1. The load voltage of the Control Unit digital outputs
The Control Units are supplied with power via the PM-IF. 24 V must also be connected in
the following cases:
– Commissioning / diagnostics when the Power Module power supply is switched-out.
– Using the digital outputs CU310-2
2. The electronics of Sensor Modules
3. The Safe Brake Relay (motor holding brakes)
Other loads can be connected to these power supply units if they are separately protected
from overcurrent.
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Manual, 06/2019, 6SL3097-5AL00-0BP1
AC Drive