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Optional Hookup for High Power PoE Devices
ET1551U Units
Note: This installation is for connecting to devices that do not have their own separate power supply and
need to be powered via PoE.
In some cases the PoE device connected at the transmitter end needs more power than can be supported over a
long Twisted Pair run. You can usually identify these cases by watching the POWER LED of the transmitter, located
on the “Network Port”. If the power light cycles ON for less then 1 second and then is off for 3 or 4 seconds when
the PoE device is connected, but it turns ON and operates normally without a PoE device connected, this would
indicate you are having a current limit problem.
At the camera location securely mount the ET1551 transmitter. The ET1551 can provide full 802.3at power to oper-
ate most IP cameras and other PoE devices, when powered directly from a 48VDC supply. Either use the PS48
Power Supply from Nitek or other 48VDC power supply to operate the units. The illustration below shows the use of
the PS48 supply. Other DC power supplies can be used with the supplied power connector if desired but must be
48 to 56 VDC for proper operation.
Distance from
Network Port
PoE Device Power
Available
30ft/10m 33
watts
325ft/100m 26
watts
Transmitter used as
PoE Injector*
*
Results with 48VDC power to the
Transmitter optional Power Port
48VDC Powered Transmitter Hookup Diagram
PS48
ET1551
Twisted Pair from
Head-end
Link
Port
IP Camera
Network
Port
115 VAC
Optional
48VDC
Supply