Phoenix Contact 1708 M12 POE, User Manual, Page: 21 / 34

Startup and function
105648_en_01 PHOENIX CONTACT
21
Example 3:
Overload by the PD at port 2
PD at port 2 is disconnected by the PSE system,
the LED at port 2 flashes at 5 Hz
FAIL LED: On
Relay: Open
Total power falls to 146 W, the
PoE LEDs of port 1 and port 3 to port 6 are active
Figure 3-3 Example 3 of the display behavior
3.4 Frame switching
The switch operates in store-and-forward mode. When receiving a data packet, the switch
analyzes the source and destination addresses. The switch stores up to 4000 MAC ad-
dresses with an aging time of 40 seconds in its address table.
3.4.1 Store and forward
All data telegrams received by the switch are stored and checked for validity. Invalid or
faulty data packets and fragments (<64 bytes) are rejected. Valid data telegrams are for-
warded by the switch.
3.4.2 Multi-address function
The switch learns all the source addresses for each port. Only packets with:
– Unknown source addresses
– A source address for this port or
– A multicast/broadcast address
30W
PD4
30W
PD3
PD2
26W
PD1
30W
PD6
30W
PD5 PD7
Rel ai s
Ü b erl a s t