PowerDsine PD-6548 - Manual (Page 10)

PD-6548
Power over Ethernet Solutions 10 Cat. No.: 06-6860-056
2 About the Power over Ethernet
Midspan
PowerDsine’s Midspans family, injects DC power over data-carrying Ethernet
cabling. The PD-6548 Midspan, supports 48 ports in a 10/100BaseTx Ethernet
network, over TIA/EIA-568 Category 5/5e/6 cabling. DC operating power, for
data terminal units, is fed over the unused pairs of the cabling (7/8 and 4/5).
The Midspan powers devices that are Power over Ethernet enabled, or are
equipped to receive power over Ethernet. These devices are called Powered
Devices (PDs). Devices that are not equipped to receive power over Ethernet,
may require an external power adapter in order to be powered. Contact
PowerDsine for such an adapter.
The Power over Ethernet Midspan main features are as follows:
„ Remote power feeding over standard Ethernet ports
„ Eliminates the need for AC outlets, local UPS & AC/DC adapters
near PDs
„ Universal range power input (100-240 VAC, 50/60 Hz)
„ Power management
„ Remote Web manager (optional)
„ Overload and short-circuit protection per channel
„ Port status indications
„ Standard 19-inch rack mountable
2.1 Power Management
When establishing a network, the total power required by PDs may exceed the
total power available from the Midspan. The built-in Power Management
feature does not allow the total power output to exceed the maximum power
available (refer to the Technical Specifications). When the total power
available is close to the maximum value, attempts to connect an additional PD
to a free port cause the corresponding port LED to blink green at an 0.5 sec.
rate, indicating an out-of-power budget, thus, this port will not deliver power.
The power distribution method is based on “First Come, First Served” logic.
Sometimes, connected operating PDs significantly increase or suddenly raise
their power requirements. If the required power exceeds the available power,
the Power over Ethernet Midspan starts to turn off ports in accordance with
their priority (the first turned off port is the lower priority port) until the total
power is once again under the maximum limit. Default priority is establishid by
port number: the higher the port number is, the lower priority it gets.