User's Manual

RX INN Installation Guide Page: 14
header J1 and is not surge protected or EMI filtered. The UART0 serial connector is not
accessible when the board is installed in its enclosure.
Power Connection
The input power to the RX INN is through an external DC power supply to the Power
Connector, or via passive PoE at Ethernet port, ETH0. Both the PoE and the coaxial power
inputs are electrically isolated from all other circuitry on the RX INN to 1500Vrms.
If power is connected to both the power jack and the passive PoE simultaneously, no harm
will be done, but in that case, the RX INN will draw current from the supply on the power jack.
The External supplies must be connected with the correct polarity. A supply connected in the
reverse polarity will not cause any harm to RX INN or itself since there is reverse polarity
protection built into Pronghorn Metro main board; it simply won’t power anything. The polarity
is explained in the following table.
J11, Power
Jack Pin
Signal Name J10*, Ethernet
Pin
Signal Name
1 – Center 48V-DC-Power+ 4,5 48V-passive-PoE+
3 – Outer 48V-DC-Power- 7,8 48V-passive-PoE-
1,2 Ethernet Tx pair**
3,6 Ethernet Rx pair**
*NOTE: If passive PoE power is inadvertently applied to the other Ethernet
port, J9, there is no risk of damage. Nothing will happen.
**NOTE: Do not energize pins 1,2,3,6 on any Ethernet port with PoE
power! That could cause damage to the RX INN and void warranty. (If an
IEEE802.3af compliant PSE is inadvertently attached, there is no risk of
damage. The PSE will not energize these pairs because it requires the PD to
identify itself as IEEE802.3af compliant.)
The voltage from the external supplies must be within the PoE range +36V to +60V, (+48V
nominal) at the input to RX INN.
Up to 25W can be supplied on a continuous basis to the four MiniPCI slots. The architecture
of the RX INN’s power supply allows this 25W to be delivered all at 3.3V, all at 5V, or in any
combination of 3.3V and 5V not exceeding 25W.
Regardless of the port used to power the RX INN, the supply must be able to provide enough
current for the RX INN application including the radios.
The PoE input and 48VDC local power inputs are both electrically isolated from the
Pronghorn Metro’s other circuitry by 1500V
RMS
isolation. This is important in outdoor and
remotely mounted applications to control ground loops, to minimize noise, and to assist with
managing surges.
NOTE: In the event power supplies are connected to both the power jack and
passive PoE inputs simultaneously, each external supply must offer electrical
isolation. Since the conductors from each supply will be brought in proximity
to one another spurious energy on the Ethernet lines could be conducted into
the power supply connected to the power jack. Pronghorn Metro isolates its