Redundant Power Supply - Siemens SCALANCE X-300EEC Compact Operating Instructions

Connecting to the power supply (SELV)
● The power supply is connected using a 4-pin plug-in terminal block.
● The power supply can be connected redundantly. Both inputs are isolated. There is no
distribution of load. When a redundant power supply is used, the power supply unit with
the higher output voltage supplies the IE Switch X-300 alone.
● The power supply is connected over a high resistance with the enclosure to allow an
ungrounded set up. The two power inputs are non-floating.
Terminal block assignment (4-pin)
Table 5- 4
Pin number
Pin 1
Pin 2
Pin 3
Pin 4
To wire up the power connector, use a copper cable of category 18-12 AWG or cable with a
cross-section of 0.75 to 2.5 mm².
5.4.1.3

Redundant power supply

Redundancy with the 24...48 V power supply of the IE Switch X-300EEC
The X-300EEC is available with a single or redundant power supply unit to supply 24...48 V
DC. Each power supply unit is monitored for power failure.
The IE Switches X-300EEC therefore provide the following options for redundancy of the
24...48 V DC power supply:
● Redundant power supply with 1 power supply unit
You can connect a redundant power supply to each 24...48 V DC power supply unit.
● Redundant power supply units 24...48 V DC
Connect 1 power supply to each power supply unit.
Since both power supply units have 2 connectors for redundant power supply, you can
connect 2 power supplies to each of the two power supply units. This should, however,
only be necessary in extremely rare situations.
Note
Connection with redundant power supply units 24...48 V DC
If you connect an X-300EEC with redundant power supply units 24...48 V DC to two
power supplies, you will need to connect the power supply to terminal "L1" on both power
supply units.
Only "L1" is monitored on each connector.
SCALANCE X-300EEC
Compact Operating Instructions, 11/2015, A5E02630809-09
Pinout of the 24 to 48 V safety extra-low voltage (SELV)
Assignment
L1+ (24 to 48 VDC)
M1
M2
L2+ (24...48 V DC)
Connecting
5.4 Power supply
45