Local And Line Powering - ADC HiGain HRU-402 User Manual

150-402-100-03

Local and Line Powering

The HRU-402 List 1 can be line or locally powered. The remote unit always
chooses the local -48 Vdc from the power supply attached to pair 35 (-) and
17 (+) of the card-edge connector. To set local or line power for the HRU-402
List 1, switch the Local Power (LPWR) switch S1 to ENA (see
page 8 for switch location). When LPWR is set to DIS, the HRU must be line
powered.
The HRU-402 List 3 is locally powered. It cannot be line powered. This
feature makes the HRU-402 List 3 compatible with remote cellular phone
sites located in high voltage power towers. Such applications require the
HRU to be CD isolated from the network to avoid damage due to ground fault
potential risk. The -20 to -70 wide input voltage range also makes the
HRU-402 List 3 compatible with the standard -24V power supplier common
to cellular phone sites. The remote unit uses the power source attached to pins
35(-) and 17(+) of the card-edge connector
The earlier versions of the HLU-231 (Lists 1, 2, 3, 3A and 4) must first have
their Power Feed (PWRF) user option set to DIS when connected with a
locally powered HRU-402 List 3 unit.
The following line units automatically turn off their line power supply when
they are connected to a local powered HRU-402:
•
List 6 and higher versions of the HLU-231
•
All versions of the HLU-319 and HLU-388
Refer to the appropriate HLU user manual if you need more information
about its local powering capabilities.
If local power is lost to an HRU-402 List 1, the lost span loses sync. When
the HLU or HDU attempts to reestablish sync, it detects that the remote unit
is not locally powered and applies line power to it. The remote then powers
up and operates normally if it is within range to support line powering.
The HRU-402 List 1, when locally powered, must use a -48V power supply
capable of 110mA capacity (5.2 W).
HRU-402 List 1 and List 3
(Figure 25 on page
November 5, 1998
Product Overview
Figure 3 on
50).
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