PairGain HLU-431, Быстрое руководство по установке

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Testing 350-431-116-01, Revision 01
18 January 8, 1999 HLU-431 List 1F
reinserted onto the outgoing HDSL pairs through a holding coil and then sent
on to power the doubler. This equipment is used to provide high voltage
metallic isolation between the HLU and the cable network. Such isolation is
required when the HLU can be exposed to Ground Potential Rise (GPR)
faults that can occur. For example, if the HLU is located in a power utility
substation or on a high voltage tower. The maximum input voltage that the
dc-to-dc converter can tolerate is 150V which makes it compatible with the
HLU-431 List 1F whose maximum output voltage is 140V. For more
information on the HDSL-compatible HVP equipment, contact Positron at
303-688-5800.
Although compatible with HiGain, the placement of Positron
equipment in HiGain HDSL circuits does slightly degrade
circuit margins. To ensure an adequate margin under all
operating conditions, PairGain recommends that the
maximum range of HiGain spans that contain Positron DC
isolation equipment be reduced from 35 dB to 31 dB.