ADC PG-PLUS PLL-720 Instructions for use

PG-PLUS
TECHNICAL PRACTICE
SECTION SCP-PLL720-020-03H
Model List CLEI Code
PLL-720 2S9L1AADA~~
PLL-721 2S9L1ABDA~~
4 POTS/6 POTS
CENTRAL OFFICE LINE UNIT
LIST
PG-PLUS
PLL-721
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
PG-PLUS
PLL-720
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
PWR

SCP-PLL720-020-03H
January 6, 2003 PLL-720, PLL-721 List 2’s
Revision History of This Practice
©Copyright 2003 ADC DSL Systems, Inc. All Rights Reserved.
ADC is a registered trademark of ADC Telecommunications,Inc. PG-Plus is a registered trademark of ADC DSL Systems, Inc. No right,
license, or interest to such trademarks is granted hereunder, and you agree that you shall assert no such right, license, or interest
with respect to such trademarks. Other product names mentioned in this document are used for identification purposes only and
may be trademarks or registered trademarks of their respective companies.
Information contained in this document is company private to ADC DSL Systems, Inc., and shall not be modified, used, copied,
reproduced or disclosed in whole or in part without the written consent of ADC.
Contents herein are current as of the date of publication. ADC reserves the right to change specifications at any time without notice.
Information furnished by ADC is believed to be accurate and reliable. In no event shall ADC be liable for any damages resulting
from the loss of data, loss of use, or loss of profits and ADC further disclaims any and all liability for indirect, incidental, special,
consequential or other similar damages. This disclaimer of liability applies to all products, publications and services during and
after the warranty period.
Revision Release Date Revisions Made
01 December 15, 2000 Initial Release
02 February 6, 2002 Release to rebrand document to comply with ADC standards
03 January 6, 2003 Updated Product Support Information

SCP-PLL720-020-03H Using This Practice
PLL-720, PLL-721 List 2’s January 6, 2003
USING THIS PRACTICE
Three types of messages, identified by icons, appear in the text.
INSPECTING YOUR SHIPMENT
Upon receipt of the equipment:
•Unpack each container and visually inspect the contents for signs of damage. If the equipment has been
damaged in transit, immediately report the extent of damage to the transportation company and to ADC.
Order replacement equipment, if necessary.
•Check the packing list to ensure complete and accurate shipment of each listed item. If the shipment is short
or irregular, contact ADC as described in “Returns” on page 55. If you must store the equipment for a
prolonged period, store the equipment in its original container.
Notes indicate information about special circumstances.
Cautions indicate the possibility of equipment damage or the possibility of personal injury.
Electrostatic Discharge (ESD) susceptibility symbols indicate that a device or assembly is
susceptible to damage from electrostatic discharge.You must wear an antistatic wrist strap
connected to the appropriate ground connection prior to performing installation procedures.
You must also observe normal ESD precautions when handling electronic equipment. Do not
hold electronic plugs by their edges. Do not touch components or circuitry.

Inspecting Your Shipment SCP-PLL720-020-03H
January 6, 2003 PLL-720, PLL-721 List 2’s

SCP-PLL720-020-03H
PLL-720/721 List 2’s January 6, 2003 i
TABLE OF CONTENTS
Overview ____________________________________________________________________________ 1
Description and Features....................................................................................................................1
Metallic Fallback................................................................................................................................1
Specifications .....................................................................................................................................2
Power Consumption and Heat Dissipation ........................................................................................3
Monitoring, History, and Diagnostics .................................................................................3
Performance Parameters ......................................................................................................4
Alarms .................................................................................................................................4
Alarm Types ........................................................................................................................5
History .................................................................................................................................5
LED Descriptions...............................................................................................................................6
Installation and Test___________________________________________________________________ 7
Required Tools and Test Equipment..................................................................................................7
Installing the COLU...........................................................................................................................8
Initialization Sequence.......................................................................................................................8
Subscriber Drop Tests........................................................................................................................9
Administration _______________________________________________________________________ 9
Connecting to a Terminal or Modem...............................................................................................10
Logging On ......................................................................................................................................12
Logging Off......................................................................................................................................15
COLU Main Screen .........................................................................................................................16
COLU Menu Bar Selections..............................................................................................17
COLU Menu Structure ......................................................................................................17
Main Summary Screen ......................................................................................................18
Performance Submenu .....................................................................................................................20
HDSL Summary Screen ....................................................................................................21
HDSL 24-Hour History Screen .........................................................................................23
HDSL 7-day History Screen..............................................................................................25
Alarms Submenu..............................................................................................................................27
System History Screen.......................................................................................................28
HDSL History Screen........................................................................................................30
Configuration Submenu ...................................................................................................................33
System Options Screen......................................................................................................34
System Alarm Types Screen..............................................................................................37
HDSL Alarm Thresholds Screen.......................................................................................39
HDSL Alarm Types Screen...............................................................................................42

SCP-PLL720-020-03H
ii January 6, 2003 PLL-720/721 List 2’s
Set Factory Defaults.......................................................................................................... 45
Test Submenu .................................................................................................................................. 47
Information Submenu...................................................................................................................... 49
Inventory Screen ............................................................................................................... 50
COLU Event Log .............................................................................................................. 51
Help Screen ....................................................................................................................... 52
Fault Isolation _______________________________________________________________________ 53
COLU and RT Fault Indicators ....................................................................................................... 53
Subscriber Reported Faults.............................................................................................................. 54
Product Support _____________________________________________________________________ 55
Technical Support............................................................................................................................ 55
Limited Warranty ............................................................................................................................ 55
Returns............................................................................................................................................. 55
FCC Class A Compliance................................................................................................................ 57
Modifications................................................................................................................................... 57
Acronyms___________________________________________________________________________ 58

SCP-PLL720-020-03H
PLL-720/721 List 2’s January 6, 2003 iii
LIST OF FIGURES
1. Typical PG-Plus Application...........................................................................................................................1
2. Front Panel LEDs ............................................................................................................................................6
3. Craft Port to Terminal Connections ..............................................................................................................10
4. Craft Port to Modem Connections.................................................................................................................10
5. Menu Tree .....................................................................................................................................................17

SCP-PLL720-020-03H
iv January 6, 2003 PLL-720/721 List 2’s

SCP-PLL720-020-03H
PLL-720/721 List 2’s January 6, 2003 v
LIST OF TABLES
1. Power Consumption and Heat Dissipation.......................................................................................................3
2. LED Descriptions ............................................................................................................................................7
3. Modem Settings.............................................................................................................................................11
4. COLU Menu Bar Selections..........................................................................................................................17
5. System Status.................................................................................................................................................19
6. System History Alarms Screen......................................................................................................................30
7. HDSL History Alarms...................................................................................................................................32
8. System Options Configuration Fields ...........................................................................................................36
9. System Alarm Types .....................................................................................................................................39
10. HDSL Alarm Threshold Fields .....................................................................................................................42
11. Alarm Reports ...............................................................................................................................................44
12. HDSL Alarm Types.......................................................................................................................................45
13. COLU Event Log ..........................................................................................................................................52

SCP-PLL720-020-03H
vi January 6, 2003 PLL-720/721 List 2’s

SCP-PLL720-020-03H Description and Features
PLL-720, PLL-721 List 2’s January 6, 2003 1
OVERVIEW
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.
DESCRIPTION AND FEATURES
A PG-Plus application, consisting of one COTS, one COLU and one RT, (see Figure 1) provides bidirectional
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.
Figure 1. Typical PG-Plus Application
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.
METALLIC FALLBACK
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.
Other RTs
Alarm relays
Remote ACO
Craft port
HDSL Pair
PRL-771
PRL-770
CO
T
S
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
PG-PLUS
PLL-721
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAUL T
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
FAULT
PWR
LIST
PG-FLEX
PMX-744
PLUS
PG-FLEX
PMX-744
PLUS
PG-FLEX
PMU-712
PLUS
ACTIVE ACTIVE
TEST TEST
FAULT
DSX#1 DSX#1
DSX#5 DSX#5
DSX#2 DSX#2
DSX#6 DSX#6
DSX#3 DSX#3
DSX#7 DSX#7
DSX#4 DSX#4
DSX#8 DSX#8
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
PG-PLUS
PLL-721
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
PG-PLUS
PLL-721
LIST
SYNC
MARGIN
BYPASS
FAUL T
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
PG-PLUS
PLL-721

Specifications SCP-PLL720-020-03H
2 January 6, 2003 PLL-720, PLL-721 List 2’s
SPECIFICATIONS
Function PLL-720 4 POTS PLL-721 6 POTS
System
Resistive Signature Tip to Ground 162 K
Ring to Ground 453 K
Tip to Ground 162 K
Ring to Ground 453 K
Power Supply
Voltage Safety A2 compliant per GR-1089-CORE A2 compliant per GR-1089-CORE
Input Voltage -42 Vdc to -56.5 Vdc -42 Vdc to -56.5 Vdc
HDSL Line
Output Voltage + 140 Vdc maximum + 140 Vdc maximum
Output Power 27 Watts maximum 27 Watts maximum
HDSL Line Code 2B1Q 2B1Q
HDSL Line Rate 130.6 K symbols/sec (261.3 Kbps) 196 K symbols/sec (392 Kbps)
HDSL Reach 26 AWG - 15.0 kft (4.75 km)
24 AWG - 21.7 kft (6.61 km)
22 AWG - 31.2 kft (9.51 km)
19 AWG - 49.7 kft (15.1 km)
26 AWG - 12.5 kft (3.81 km)
24 AWG - 18.0 kft (5.48 km)
22 AWG - 25.2 kft (7.68 km)
19 AWG - 37.8 kft (11.5 km)
Maximum Line Attenuation 45.9 dB at 65 kHz 41.6 dB at 98 kHz
POTS
Analog Impedance 900Ω900Ω
DC On-hook Resistance 4 MΩminimum 4Ωminimum
DC Off-hook Resistance 1000Ωmaximum 1000Ωmaximum
COTS Input Impedance 0.9 REN @ 20 Hz maximum 0.9 REN @ 20 Hz maximum
COTS Ring Detection 65 Vrms minimum @ 15 to 50 Hz 65 Vrms minimum @ 15 to 50 Hz
Environment
Operating Temperature -40° F to +150° F (-40° C to +65° C) -40° F to +150° F (-40° C to +65° C)
Operating Humidity 5% to 95% noncondensing 5% to 95% noncondensing
Altitude -200 ft. to 13,000 ft. (-60m to 4,000m) -200 ft. to 13,000 ft. (-60 m to 4,000 m)
Vibration NEBS NEBS
ESD Per GR-1089-CORE Per GR-1089-CORE
Power and Lightning Per GR-1089-CORE Per GR-1089-CORE
Human Safety UL 1950 for Restricted Access UL 1950 for Restricted Access
Emissions Radiation and Immunity Per GR-1089-CORE for class A
equipment
Per GR-1089-CORE for class A equipment
Connector 50 gold-plated card edge fingers 50 gold-plated card edge fingers
Dimensions
Height 5.5 in. (14.0 cm.) 5.5 in. (14.0 cm.)
Width 1.1 in. (2.8 cm.) 1.1 in. (2.8 cm.)
Depth 10.25 in. (26.0 cm.) 10.25 in. (26.0 cm.)
Weight 2.0 lbs. (0.9 kg.) 2.0 lbs. (0.9 kg.)

SCP-PLL720-020-03H Power Consumption and Heat Dissipation
PLL-720, PLL-721 List 2’s January 6, 2003 3
POWER CONSUMPTION AND HEAT DISSIPATION
Monitoring, History, and Diagnostics
The COLU provides real-time, nondisruptive monitoring of HDSL transmission performance parameters for all
units in a circuit. You can set threshold values for the performance monitoring measurements at the appropriate
COLU screen. Alarms are activated at the designated threshold setting. The user interface ports performance is
also monitored. Monitored parameters include:
•HDSLNoise margin, insertion loss, ES, UAS
•InterfaceES and UAS seconds
•Major Alarm RelayForm-C relay contacts (NO, NC, C). Fail-safe operation
The worst case conditions under which these parameters are measured include a 15,000 ft., #26 AWG loop,
a fully loaded COTS, a -42.5 Vdc COTS battery voltage and a 40° C outdoor temperature.
Table 1. Power Consumption and Heat Dissipation
Power 4 POTS
COLU Slot
19-inch
COTS*
(*) The PCS-718 List 1 is shown as loaded with one PMU-712, two PMX-744, and 12 PLL-720s.
23-inch
COTS†
(†) The PCS-719 List 1 is shown as loaded with one PMU-712, two PMX-744, and 16 PLL-720s.
6 POTS
COLU Slot
19-inch
COTS‡
(‡) The PCS-718 List 1 is shown as loaded with one PMU-712, two PMX-744, and 12 PLL-721s
23-inch
COTS**
(**) The PCS-719 List 1 is shown as loaded with one PMU-712, two PMX-744, and 16 PLL-721s.
Maximum Heat Dissipation
HDSL Line Power Off 2.8 W 33.6 W 44.8 W 3.1 W 37.2 W 49.6 W
HDSL Line Power On 5.0 W 60 W 80 W 6.5 W 78 W 104 W
Maximum Power Consumption
HDSL Line Power Off 3.0 W 36 W 48 W 3.1 W 37.2 W 49.6 W
HDSL Line Power On 27.8 W 333.6 W 444.8 W 31.25 W 375 W 500 W
Maximum Current Drain
HDSL Line Power Off 71 mA 0.852 A 1.14 A 73 mA 0.875 A 1.17 A
HDSL Line Power On 654 mA 7.85 A 10.5 A 735 mA 8.82 A 11.76 A

Power Consumption and Heat Dissipation SCP-PLL720-020-03H
4 January 6, 2003 PLL-720, PLL-721 List 2’s
Performance Parameters
Based on the monitored parameters, the COLU derives the following performance parameters:
•MAR – A measure of the ratio of signal power to noise power, in dB, at a receiver point. A value of 0 dB
means that the predicted transmission BER is equal to 10-7, a value of 6 dB means the predicted transmission
BER is equal to 10-10. The Main menu option Status Summary displays continuous updates of the margin
value. You can set the high and low values of this parameter for the COLU and the RT at the “System Alarm
Types Screen” on page 37 and the severity of the alarm at the “System Alarm Types Screen” on page 37.
View the results of these settings at the “Main Summary Screen” on page 18
•LOSW – The COLU detected an error in one or more bits in five consecutive HDSL SYNC words. Five
consecutive SYNC words must be received without error to clear this condition. A LOSW condition generally
indicates the loop is down, thus data cannot be transmitted. The COLU uses this parameter to derive UAS
performance parameter. You can set the severity of the alarm at the “HDSL Alarm Thresholds Screen” on
page 39. View the results of these settings at the “HDSL Summary Screen” on page 21.
•HDSL ES – An interval of 1 second during which at least one CRC is detected at the incoming HDSL port.
You can set the value of this parameter for the COLU and the RT at the “System Alarm Types Screen” on
page 37, and at the “From the CONFIG submenu you can perform the following tasks:” on page 33 set the
severity of the alarm. View the results of these settings at the “HDSL Summary Screen” on page 21.
•HDSL UAS – An interval of 1 second during which a loop is down. You can set the value of this parameter
for the COLU and the RT at the “System Alarm Types Screen” on page 37 and at the “System Alarm Types
Screen” on page 37 set the severity of the alarm. You can view the results of these settings at the “HDSL
Summary Screen” on page 21.
Alarms
The COLU generates alarms for problem conditions on the HDSL transmission facility and at the application
interface. You can view the alarm status from the “COLU Main Screen” on page 16.
•MAR – The margin default value or a value you selected has been reached, or the unit is below the current
threshold value set.
•ES – The errored seconds are measured by both 15-minute or 24-hour thresholds. The threshold has been
reached or exceeded if an alarm exists.
•UAS – The unavailable seconds are measured by both 15-minute or 24-hour thresholds. The threshold has
been reached or exceeded if an alarm exists.
•PFO – The COLU cannot power the RTs due to an open circuit.
•PFS – The COLU cannot power the RTs due to a short circuit.
•PGF – The COLU cannot power the RTs due to HDSL Tip or Ring Fault to GND.
•LOSW – If the alarm is on the COLU, then the COLU cannot synchronize with the A or B RT, then both the
COLU and the A or B RT are out of service. If the alarm is on the RTs, then the A or B RTs cannot
synchronize with the COLU, and the COLU and either RT A or B are out of service.
•MISPWRn– Power supply n is missing (where n is A or B).
•MISMATCHn– Incompatible RTnunit is installed (where n is A or B). For example, a COLU List 1 has been
connected to a 2 ISDN RT.
•NORTSWn– RTnhas no application software and is awaiting software download (where n is A or B).

SCP-PLL720-020-03H Power Consumption and Heat Dissipation
PLL-720, PLL-721 List 2’s January 6, 2003 5
Alarm Types
At the “System Alarm Types Screen” described on page 37 you can set the alarm to any of these values:
•Critical (CR) – Alarms of this value are reported to the PMU or PAU, the Fault LED is lighted, and the alarm
history page is updated.
•Major (MJ) – Alarms of this value are reported to the PMU or PAU, the Fault LED is lighted, and the alarm
history page is updated.
•Minor (MN) – Alarms of this value are reported to the PMU or PAU, the Fault LED is lighted, and the alarm
history page is updated.
•Not Alarmed (NA) – Alarms of this value are not reported to the PMU or PAU, the Fault LED is not lighted,
and the alarm history page is not updated.
•Not Reported (NR) – Alarms of this value are not reported to the PMU or PAU, the Fault LED is lighted, and
the alarm history page is updated.
History
Current cumulative counts of the past 24 hours and historical data in the form of a 24-hour history (in 15-minute
increments) and a 7-day history (in 24-hour increments) are available to assist you in identifying problem sources.
You can view the HDSL history from the “HDSL History Screen” on page 30
•HDSL Interface – 24-Hour (15-minute intervals) and 7-Day (24-hour intervals) for ES and UAS
•Alarm – Time stamp of first and last occurrence, number of occurrences for all enabled alarms

LED Descriptions SCP-PLL720-020-03H
6 January 6, 2003 PLL-720, PLL-721 List 2’s
LED DESCRIPTIONS
Table 2 describes the LED shown on the front panel, where nequals the POTS line. For further details on the LED
activities, refer to “Initialization Sequence” on page 8 and the “COLU and RT Fault Indicators” on page 53.
Figure 2. Front Panel LEDs
LIST
PG-PLUS
PLL-721
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
PG-PLUS
PLL-720
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
PWR
Status LEDs
Status LEDs
Retaining Latc
h
Retaining Latch

SCP-PLL720-020-03H Required Tools and Test Equipment
PLL-720, PLL-721 List 2’s January 6, 2003 7
INSTALLATION AND TEST
REQUIRED TOOLS AND TEST EQUIPMENT
No tools are required to install the COLU. For testing, the following tools may be utilized:
•Telephone test set
•Optional, PSU-795 List 1 COTS Continuity Test Card, part number 150-1695-01
Table 2. LED Descriptions
LED Color State Mode
PWR Green On, all other LEDs flashing at 1 Hz Running in Boot Mode due to invalid Application Program.
On, POTSnLEDs On, all other LEDs
running downward at 1 Hz
Active software download of the COLU.
On, POTSnLEDs On, all other LEDs
running upward at 1 Hz
Active software download of the RT connected to the
COLU.
On COLU is powered and power provided to the HDSL pair is
normal.
Flashing One battery feed is missing or a battery feed fuse on the
COLU is blown.
On, and FAULT flashing DC power provided to the HDSL pair is out of normal range.
SYNC Green On COLU is in Metallic Fallback, unless provisioned Disable.
On, and POTSn flashing SDT is occurring on POTSn.
MARGI
N
Yellow On COLU HDSL margin is equal to or below the threshold
value
Flashing RT HDSL margin is equal to or below the threshold value.
BYPAS
S
Yellow On COLU is in Metallic Fallback, unless provisioned Disable.
and POTSnFlashing SDT is occurring on POTSn.
FAULT Red On COLU has a fault
Flashing Alarm condition exists on the COLU
POTSn Green On Channel is off-hook
Flashing (following Ring Cadence) Channel is ringing
Observe normal electrostatic discharge precautions when handling electronic equipment. Do not hold
electronic plugs by their edge. Do not touch components or circuitry.
The following procedure assumes that an RT is installed in the system and all wiring between the CO and
the RT has been completed and verified.

Installing the COLU SCP-PLL720-020-03H
8 January 6, 2003 PLL-720, PLL-721 List 2’s
INSTALLING THE COLU
You can install the COLU in any slot except the three positions labeled COMMON, MUX 1, and MUX 2. Refer
to the cabling tables provided in the COTS documentation for slot and telco cabling assignment.
1. Open the retaining latch on the front of the COLU.
2. Insert the COLU into the card guides in a vacant slot in the COTS that corresponds to the location of the
wiring from the CO switch.
3. Engage the retaining latch to hold the card in place.
INITIALIZATION SEQUENCE
The COLU continuously attempts to power up the RTs until end-to-end HDSL synchronization is established. If
the COLU is unable to establish synchronization, it powers down the loops and waits 5 minutes before re-trying.
1. When the COLU is installed with power applied to the COTS, all LEDs turn on for about 1 second then go
off, except for the PWR LED.
2. After approximately 5 to 19 seconds, the PWR LED flashes.
3. The COLU attempts to power up the RTs. Depending on the condition of the HDSL pair, one of the following
occurs:
a. The pair is open between the COLU and RTs:
•The PWR LED flashes for approximately 12 seconds, then remains on.
•The SYNC LED flashes for approximately 6 seconds, then remains off.
•A DSL PFO alarm is indicated on the “HDSL History Screen” on page 30.
•The COLU waits 1 minute, then goes back to step 3.
b. One, or more, pairs are shorted or grounded between the COLU and RTs:
•The PWR LED flashes for approximately 12 seconds, then remains on.
•A DSL PFS alarm is indicated on the “HDSL History Screen” on page 30.
•The SYNC LED flashes for approximately 6 seconds, then remains off.
•A DSL PFO alarm is indicated on the “HDSL History Screen” on page 30.
•The COLU waits 1 minute, then go back to step 3.
The COLU initialization and power up sequence described below assumes that the HDSL and auxiliary
power pairs are wired from the COTS and terminated at the RTs. It also assumes the COTS has been wired
to CO battery, the bay fuses are installed, and the RTs are installed.
To prevent the COLU from attempting to power up simultaneously, there is a 2 second delay between each
system in the COTS. For example, a COLU installed in slot 4 will power up 2 seconds after the COLU
installed in slot 2, and a COLU installed in slot 12 will power up 10 seconds after the COLU installed in slot
2. This delay is dependent on the COTS slot in which the COLU is installed, rather than on the number of
COLUs already installed in the COTS.

SCP-PLL720-020-03H Subscriber Drop Tests
PLL-720, PLL-721 List 2’s January 6, 2003 9
c. All pairs are good, and all correctly wired between the COLU and RTs:
•The PWR LED flashes for approximately 12 seconds, then remains on.
•The SYNC LED flashes and the COLU attempts to synchronize with the RTs. One of the following
occurs:
–The COLU does not detect, or is unable to synchronize with, an RTs:
The SYNC LED flashes for approximately 1 minute, then remains off.
The COLU waits 1 minute, then goes back to step 3.
–The COLU detects, and is able to synchronize with, an RTs:
The COLU waits 1 minute, then goes back to step 3.
–The COLU detects, and is able to synchronize with, an RTs:
Within 1 minute, the SYNC LED remains on and the COLU establishes synchronized HDSL
communications with the RTs. Assuming the HDSL margins are above alarm thresholds, and there
are no subscriber drop tests or other alarms or faults in the system, the COLU LEDs are in the
following states:
PWR is on
SYNC is on
MARGIN is off
TEST is off
ALARM is off
FAULT is off
SUBSCRIBER DROP TESTS
You can perform this function in one of two ways (see “Test Submenu” on page 47):
•Initiate a test by applying +116 V on the Tip side of the POTS circuit at the COLU through a loop test system.
•With the VT-100 terminal connected to the PMU maintenance port, select the Subscriber Drop Test feature
from the Test menu. Relays on the RT provide a path for performing a SDT. The results are displayed on the
VT-100 terminal and presented as TA-909 resistive signatures on the COLU Tip and Ring.
ADMINISTRATION
With a VT-100 terminal, you can access the craft port of the PMU or the PAU to review system administration
functions, such as alarm checking and clearing, configuration changes, performance monitoring, and testing the
PG-Plus through the craft terminal screens.
It may take up to 4 minutes before end-to-end synchronization is established.

Connecting to a Terminal or Modem SCP-PLL720-020-03H
10 January 6, 2003 PLL-720, PLL-721 List 2’s
CONNECTING TO ATERMINAL OR MODEM
Connections between the craft port and a VT-100 terminal are shown in Figure 3 for both DB-9 and DB-25
connectors. Although a cable can be used that connects only the transmit (TD), receive (RD), and ground (GND)
signals, the craft port does not automatically log off when the VT-100 terminal is unplugged. Using a cable that
also connects the Data Terminal Ready (DTR) signal ensures automatic log off when the VT-100 terminal is
unplugged.
Figure 3. Craft Port to Terminal Connections
When connecting the port to a modem, use a null modem cable. The wiring for this cable is shown in Figure 4.
Ensure that the modem's Carrier Detect (CD) and DTR functions are enabled. This allows the modem connection
to terminate correctly when the Alarm or PGTC Interface unit drops Data Set Ready (DSR), and the unit logs off
when the modem drops Carrier Detect.
Figure 4. Craft Port to Modem Connections
The craft port supports a VT-100 terminal. The VT-100 terminal allows real time updating of information
displayed on the screen, rather than requiring the technician to press the key to refresh the screen.
Configure the VT-100 terminal as shown in Table 3.
ENTER