Connecting; Supply Voltage X124 - Siemens SIMATIC S7-1500 Equipment Manual

Connecting

4.1

Supply voltage X124

24 V DC supply voltage (X124)
The SIMATIC Drive Controller is powered by an external 24 V DC power supply. Power
supplies from the SITOP family, for example, can be used.
Danger to life from hazardous voltage when an unsuitable power supply is connected
Design the 24 V direct voltage as protective extra-low voltage.
When an external 24 V DC power supply is connected, it must comply with the requirements
for protective extra-low voltage (PELV) according to UL 61010. A backup fuse that reliably
trips within 120 seconds in the event of a short-circuit at an ambient temperature of 0 °C
must also be available.
When OVC III circuits up to 600 V AC (phase to neutral voltage) are the primary supply of the
utilized power supply, ensure that the clearance between open contacts of the fuse or the
single-fault-secure circuit is 3.0 mm according to UL 61010.
When using an external power supply, ensure that the trip rating of the utilized fuse
corresponds to the maximum possible short-time short-circuit current of the utilized power
supply.
NOTE
Ground potential and enclosure (PE) are connected to one another internally with low
impedance. You must therefore observe the following:
• Insulation monitoring devices are not permitted in the 24 V power supply.
• If you are using external power supplies (e.g. SITOP), you must connect the ground
potential to the protective conductor terminal (PELV).
• You must provide adequately dimensioned equipotential bonding connections between
the 24 V power supply and all grounded, locally separate loads.
You can find information on equipotential bonding in the SIMATIC Drive Controller system
manual (https://support.industry.siemens.com/cs/ww/en/view/109766665).
SIMATIC Drive Controller
Equipment Manual, 11/2022, A5E46600370-AC
WARNING
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