PairGain HIGAIN HRU-412, Руководство пользователя

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Front and Rear Panel 150-412-107-03, Revision 03
8 November 19, 1999 HRU-412 List 7
Table 2. Rear Panel Components
Switch Setting Function
I-CPE 0 Sets the CPE current to 0 mA.
60 Sets the CPE current to 60 mA to power an external NID.
The CPE current control signals terminate on pins 32 and 34 of
the card-edge converter. These access pins are for factory test
only and are not used. Single slot remote enclosures and seven
slot enclosures use the pins to control the CPE options in older
HRU units. These enclosures must be optimized for 0 mA
current to prevent a conflict between external connections to
pins 32 and 34 and the settings of the I-CPE switch.
TLOS-LB DIS Does not allow the HRU-412 to enter its logic loopback state when
a loss of the T1 XMT signal from the CPE causes the HLU to
transmit the AIS signal toward the DSX-1.
EN Allows the HRU-412 to enter its logic loopback state when a loss
of the T1 XMT signal from the CPE causes the HLU to transmit the
AIS signal toward the DSX-1. While in this loopback state, the
HRU-412 transmits the AIS signal toward the CPE and returns the
network signal back to the network. The HLU displays TLOS in its
front panel display. This condition remains until a valid T1 signal is
received from the CPE or until the 3-in-5 in-band loopdown
command is issued. Once the TLOS initiated loopback occurs, it
will not reoccur until the CPE T1 signal has been reapplied and then
removed. This feature prevents the HRU-412 from oscillating into
and out of TLOS loopback when a loopdown command is issued in
the absence of a T1 signal from the CPE. This TLOS option must
never be enabled when the HRU-412 is used with old line units that
do not support this feature. These older line units (List 6 and
under) cannot loopdown an HRU-412 that is in a TLOS loop-up
state when they receive the 3-in-5 in-band loopdown command.
RLEV 0 Configures the T1 RCV level to 0 dB. This sets the T1 output signal
level from the HRU-412 toward the NI to 0 dB. Use this setting
when the HRU-412 is not functioning as a NID but is connected to
an external NID. It allows the external NID to set the appropriate NI
level.
15 Configures the T1 RCV level to -15 dB. This sets the T1 output
signal level from the HRU-412 toward the NI level to -15 dB. This
setting is recommended when the HRU-412 functions as a NID.
JP2 Allows the enabling or disabling of the sealing current. To enable,
connect JP2 across both terminals. To disable (default), remove
the jumper from the inner terminal and leave it attached to the
outer terminal only.