Overview; Description And Features; Metallic Fallback - ADC PG-PLUS PLL-720 Technical Practice

SCP-PLL720-020-03H
O
VERVIEW
®
The PG-Plus PLL-720, PLL-721 List 2's, PAU-710 List 4B, provide interface with the respective RT for four
and six POTS subscribers.
D
ESCRIPTION AND
A PG-Plus application, consisting of one COTS, one COLU and one RT, (see
transport of multiple DS0, over a single, unconditioned wire pair using HDSL technology. Using existing cable,
PG-Plus provides for higher bandwidth needs of residential and business customers by providing multiple POTS
interfaces on a single HDSL twisted-pair wire.
PG-FLEX PLUS PG-FLEX PLUS PLUS PG-PLUS PG-PLUS
PG-FLEX
PMU-712 PMX-744 PMX-744 PLL-721 PLL-721
LIST LIST LIST LIST
PWR PWR PWR PWR
ACTIVE ACTIVE SYNC SYNC
MARGIN MARGIN
TEST TEST BYPASS BYPASS
FAULT FAULT FAULT FAULT
DSX#1
DSX#1 POTS1 POTS1
DSX#2
DSX#2 POTS2 POTS2
DSX#3 DSX#3 POTS3 POTS3
DSX#4 DSX#4 POTS4 POTS4
DSX#5 DSX#5 POTS5 POTS5
DSX#6 DSX#6 POTS6 POTS6
DSX#7 DSX#7
DSX#8 DSX#8
Alarm relays
Remote ACO
Craft port
The COLU uses ADC HDSL technology to provide digital transmission without the need for repeaters, loop
conditioning, or pair selection. The COLU can be installed in the PCS-718 19-inch or the PCS-719 23-inch COTS.
The COLU operates in the standalone mode with no other COTS circuit cards required. Advanced features such
as performance monitoring, alarm reporting, and testing require the addition of the PG-Plus PAU or PMU. Line
power is provided to the RT by the COLU.
The COLU performs the interface functions between the analog POTS circuits of the CO switching system by
mapping one POTS line onto one DS0 for transmission to the RT on the HDSL pair. To obtain maximum reach,
the HDSL line to the RT is operated at the minimum rate to support the payload.
M F
ETALLIC ALLBACK
Metallic fallback provides a direct connection from the CO to one subscriber under fault conditions. Service is
provided to the first POTS subscriber on the affected system. At the RT, the system exits metallic fallback and
attempts to synchronize if either the first POTS or the HDSL Tip to Ring pair is shorted for at least 3 seconds, and
then released for at least 3 seconds. Otherwise, the COLU checks for the presence of an RT every 5 minutes. If an
RT is present, the system begins HDSL synchronization acquisition.
Relays in the COLU and RT provide a path for SDT and metallic fallback operation. These relays are used to
establish a circuit to POTS # 1 during fault conditions and to provide for drop testing of the selected subscriber
line from the CO location.
PLL-720, PLL-721 List 2's
F
EATURES
COTS
PG-PLUS PG-PLUS PG-PLUS PG-PLUS PG-PLUS PG-PLUS PG-PLUS PG-PLUS PG-PLUS PG-PLUS PG-PLUS
PLL-721 PLL-721 PLL-721 PLL-721
PLL-721 PLL-721 PLL-721 PLL-721 PLL-721 PLL-721 PLL-721
LIST LIST LIST LIST LIST LIST LIST LIST LIST LIST LIST
PWR
PWR PWR PWR PWR PWR PWR PWR PWR PWR
SYNC
SYNC SYNC SYNC SYNC SYNC SYNC SYNC SYNC SYNC
MARGIN
MARGIN MARGIN MARGIN MARGIN MARGIN MARGIN MARGIN MARGIN MARGIN MARGIN
BYPASS
BYPASS BYPASS BYPASS BYPASS BYPASS BYPASS BYPASS BYPASS BYPASS BYPASS
FAULT FAULT FAULT FAULT FAULT FAULT FAULT FAULT FAULT FAULT
POTS1
POTS1 POTS1 POTS1 POTS1 POTS1 POTS1 POTS1 POTS1 POTS1
POTS2
POTS2 POTS2 POTS2 POTS2 POTS2 POTS2 POTS2 POTS2 POTS2
POTS3 POTS3 POTS3 POTS3 POTS3 POTS3 POTS3 POTS3 POTS3
POTS3
POTS4 POTS4 POTS4 POTS4 POTS4 POTS4 POTS4 POTS4 POTS4 POTS4
POTS5 POTS5 POTS5 POTS5 POTS5 POTS5 POTS5 POTS5 POTS5 POTS5
POTS6
POTS6 POTS6 POTS6 POTS6 POTS6 POTS6 POTS6 POTS6 POTS6
Other RTs
Figure 1. Typical PG-Plus Application
January 6, 2003
PG-PLUS PG-PLUS
PG-PLUS
PLL-721 PLL-721 PLL-721
LIST LIST
LIST
PWR PWR PWR PWR
SYNC SYNC SYNC SYNC
MARGIN MARGIN MARGIN
HDSL Pair
BYPASS BYPASS BYPASS
FAULT FAULT FAULT
FAULT
POTS1 POTS1 POTS1 POTS1
POTS2 POTS2 POTS2 POTS2
POTS3 POTS3 POTS3
POTS3
POTS4 POTS4 POTS4
POTS4
POTS5 POTS5 POTS5
POTS5
POTS6 POTS6 POTS6
POTS6

Description and Features

Figure 1) provides bidirectional
PRL-770
PRL-771
1