Phoenix Contact 2700290, User Manual, Page: 16 / 154

Smart Managed Compact Switch
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PHOENIX CONTACT 8089_en_03
2.2 Installing the Smart Managed Narrow Switch
2.2.1 Connecting the 24 V DC supply voltage
The SMN is operated using a 24 V DC voltage, which is applied via COMBICON. If required,
the voltage can also be supplied redundantly (see Figure 2-4).
Figure 2-3 Supplying the SMN using one voltage source
Redundant 24 V DC supply
Figure 2-4 Supplying the SMN using two voltage sources
If redundant power supply monitoring is active (default setting), an error is indicated if only
one voltage is applied. A bridge between US1 and US2 prevents this error message.
However, it is also possible to deactivate monitoring in web-based management or via
SNMP.
OUT
24 V DC
US1 GND US2 GND R1 R2
In order to reset the SMN on power up, the power supply must be interrupted for at least
3 seconds.
OUT
24 V DC
US1 GND US2 GND R1 R2