Siemens X-400 - Manual (Page 67)

Operating Instructions for SCALANCE X-400 Industrial Ethernet Switches
C79000-G8976-C186-03
67
Installation and Commissioning
6
6.1 Installing / Removing the SCALANCE X414-3E
! Warning
SCALANCE X-400 is designed for operation with safety extra-low voltage (SELV).
This means that only safety extra-low voltages (SELV) complying with
IEC950/EN60950/ VDE0805 can be connected to the power supply terminals.
The power supply unit for the 24 V DC supply must comply with NEC Class 2
(voltage range 20.4 - 28.8 V DC, current requirement max. 2 A). If the device is
supplied with power redundantly, both power supply units together must comply
with NEC Class 2.
Exceptions:
● Power supply with PELV (according to VDE 0100-410) is also possible if the
generated rated voltage does not exceed the voltage limits 25 V AC or 60 V
DC.
● Power supply by a SELV power source (according to IEC 60950) or PELV
power source (according to VDE 0100-410) without limited power is also per-
mitted if suitable fire protection measures are taken by:
- Installation in a cabinet or suitable enclosure
- Installation in a suitably equipped, closed room
! Caution
The subject unit must be located in a Restricted Access Location where access
can only be gained by SERVICE PERSONNEL or by USERS who have been in-
structed about the reasons for the restrictions applied to the location and about any
precautions that shall be taken when operated in an air ambient of 50°C - 60°C