ADC PG-PLUS PLL-734 User manual

PG-PLUS
TECHNICAL PRACTICE
SECTION SCP-PLL734-020-03H
Model List CLEI Code
PLL-734 2S9L1APBA~~
DUAL 2 POTS
CENTRAL OFFICE LINE UNIT
LIST
PG-PLUS
PLL-734
PWR
SYNC
BYPASS
POTS1
MARGIN
FAULT
POTS2
AB

SCP-PLL734-020-03H
January 6, 2003 PLL-734 List 2
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 August 9, 2000 Initial Release
02 January 28, 2002 Release to rebrand document to comply with ADC standards
03 January 6, 2003 Updated Product Support Information

SCP-PLL734-020-03H Using This Practice
PLL-734 List 2 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 67. 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-PLL734-020-03H
January 6, 2003 PLL-734 List 2

SCP-PLL734-020-03H
PLL-734 List 2 January 6, 2003 i
TABLE OF CONTENTS
Overview ____________________________________________________________________________ 1
Description and Features....................................................................................................................1
HDSL Transmission ............................................................................................................1
Metallic Fallback .................................................................................................................2
Power Consumption and Heat Dissipation..........................................................................2
Monitoring, History, and Diagnostics .................................................................................3
Performance Parameters ......................................................................................................3
Alarms .................................................................................................................................3
Alarm Types ........................................................................................................................4
History .................................................................................................................................4
Specifications .....................................................................................................................................5
LED Descriptions...............................................................................................................................6
Installation and Test___________________________________________________________________ 8
Required Tools and Test Equipment..................................................................................................8
Installing the COLU...........................................................................................................................8
Initialization Sequence.......................................................................................................................9
Subscriber Drop Tests......................................................................................................................10
Administration ______________________________________________________________________ 11
Connecting to a Terminal or Modem...............................................................................................11
Navigational Methods ......................................................................................................................13
Logging On ......................................................................................................................................13
Logging Off......................................................................................................................................17
COLU Main Screen .........................................................................................................................18
COLU Menu Bar Selections..............................................................................................19
COLU Menu Structure ......................................................................................................20
Main Summary Screen ......................................................................................................21
Performance Submenu .....................................................................................................................23
HDSL A or B Summary Screen ........................................................................................24
HDSL A and B 24-Hour History Screen ...........................................................................26
HDSL 7-day History Screen..............................................................................................28
Alarms Submenu..............................................................................................................................30
System History Screen.......................................................................................................31
HDSL History Screen........................................................................................................33
Configuration Submenu ...................................................................................................................36
System Options Screen......................................................................................................37
System Alarm Types Screen..............................................................................................40

SCP-PLL734-020-03H
ii January 6, 2003 PLL-734 List 2
HDSL Options Screen....................................................................................................... 43
HDSL A and B Alarm Thresholds Screen ........................................................................ 46
HDSL A and B Alarm Types Screen ................................................................................ 49
Set Factory Defaults Screen.............................................................................................. 53
Test Submenu .................................................................................................................................. 54
Information Submenu...................................................................................................................... 57
COLU Inventory Screen ................................................................................................... 58
RTs Inventory Screen........................................................................................................ 58
COLU Event Log .............................................................................................................. 59
RT Event Log....................................................................................................................61
Help Screen ....................................................................................................................... 63
Fault Isolation _______________________________________________________________________ 64
COLU and RT Fault Indicators ....................................................................................................... 64
Subscriber Reported Faults.............................................................................................................. 65
Product Support _____________________________________________________________________ 67
Technical Support............................................................................................................................ 67
Limited Warranty ............................................................................................................................ 67
Returns............................................................................................................................................. 67
FCC Class A Compliance................................................................................................................ 69
Modifications................................................................................................................................... 69
Acronyms___________________________________________________________________________ 70

SCP-PLL734-020-03H
PLL-734 List 2 January 6, 2003 iii
LIST OF FIGURES
1. Typical PG-Plus Application...........................................................................................................................1
2. LED on Front Panel.........................................................................................................................................6
3. Craft Port to Terminal Connections ..............................................................................................................11
4. Craft Port to Modem Connections.................................................................................................................11
5. Menu Tree .....................................................................................................................................................20

SCP-PLL734-020-03H
iv January 6, 2003 PLL-734 List 2

SCP-PLL734-020-03H
PLL-734 List 2 January 6, 2003 v
LIST OF TABLES
1. HDSL Distances ..............................................................................................................................................2
2. Power Consumption and Heat Dissipation.......................................................................................................2
3. LED Descriptions ............................................................................................................................................7
4. Modem Settings.............................................................................................................................................12
5. COLU Menu Bar Selections..........................................................................................................................19
6. System Status.................................................................................................................................................22
7. HDSL Alarms................................................................................................................................................35
8. System Options Configuration Fields ...........................................................................................................39
9. System Alarm Types .....................................................................................................................................42
10. HDSL Options Configuration Fields.............................................................................................................45
11. HDSL Alarm Thresholds...............................................................................................................................48
12. Alarm Reports ...............................................................................................................................................51
13. HDSL Alarm Types.......................................................................................................................................52
14. COLU Event Log ..........................................................................................................................................59
15. RT Event Log ................................................................................................................................................61
16. COLU and RT Fault Indicators .....................................................................................................................64
17. Subscriber Reported Faults............................................................................................................................65

SCP-PLL734-020-03H
vi January 6, 2003 PLL-734 List 2

SCP-PLL734-020-03H Description and Features
PLL-734 List 2 January 6, 2003 1
OVERVIEW
The PG-Plus®COLU, PLL-734 List 2, provides interfaces to two 2 POTS RT, PRL-784, for four POTS
subscribers.
DESCRIPTION AND FEATURES
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. A typical application of a PG-Plus
system consists of one COTS, one COLU, and two RTs (see Figure 1).
Figure 1. Typical PG-Plus Application
The COLU uses ADC’s 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.
Line power is provided to the RTs by the COLU. Advanced features, performance monitoring, alarm reporting,
and testing require a PMU be installed.
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 RTs on the HDSL pair. To obtain maximum reach,
the HDSL line to the RT is operated at the minimum rate to support the payload.
HDSL Transmission
The PAU-710 uses ADC’s HDSL 2B1Q technology to transport 2 DS0s, plus signalling, over one copper pair to
each RT. The HDSL circuits can be used without pair selection. Adaptive equalization, scrambling, and a
four-level 2B1Q line coding scheme are used to maximize distance and minimize crosstalk.
Table 1 shows the maximum distance between the COTS and RT for various wire gauges. These distances are
shown for a cable temperature of 68º F (20º C). As the temperature of the cable increases, the distance decreases.
COTS
Other RTs
Alarm relays
Remote ACO
Craft port
PWR
SYNC
MARGIN
TEST
FAULT
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-734
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
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
SYNC
MARGIN
BYPASS
FAULT
POTS1
POTS2
POTS3
POTS4
POTS5
POTS6
PWR
LIST
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
RT-A
POTS-1
A
POTS-1B
POTS-2
A
POTS-2B
HDSL Pair
HDSL Pair
RT-B
PWR
SYNC
MARGIN
TEST
FAULT
PG-PLUS
PLL-734
LIST
PWR
SYNC
MARGIN
TEST
FAULT
PG-PLUS
PLL-734
LIST

Description and Features SCP-PLL734-020-03H
2 January 6, 2003 PLL-734 List 2
Metallic Fallback
Metallic fallback provides a direct connection from the CO to one subscriber under fault conditions. Service is
provided to the subscriber assigned to the first POTS line in the affected COLU. At the COLU, the system exits
metallic fallback and attempts to synchronize if either 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 and POTS line 1 is on-hook, the system begins HDSL synchronizationn.
Power Consumption and Heat Dissipation
Table 1. HDSL Distances
Wire Gauge HDSL Distance (6 dB Margin / 46.4 dB Loss / 33
kHz)
Analog Impedence
(900 Ω)
26 AWG
(0.40 mm)
18.0 kft
(2.8 km)
6.3 kft
(1.9 km)
24 AWG
(0.51 mm)
25.5 kft
(3.8 km)
10.2 kft
(3.1 km)
22 AWG
(0.64 mm)
36.5 kft
(5.0 km)
16.3 kft
(5.0 km)
19 AWG
(0.91 mm)
62.0 kft
(7.0 km)
32.9 kft
(10.0 km)
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 2. Power Consumption and Heat Dissipation
Power COLU Slot 19-inch COTS*
(*) The PCS-718 List 1 is shown as loaded with one PMU-712, two PMX-744, and
12 PLL-726s.
23-inch COTS†
(†) The PCS-719 List 1 is shown as loaded with one PMU-712, two PMX-744, and
16 PLL-726s.
Maximum Heat Dissipation
HDSL Line Power Off 5.0 W 50.0 W 60.0 W
HDSL Line Power On 16.5 W 119.0 W 152.0 W
Maximum Power Consumption
HDSL Line Power Off 5.0 W 50.0 W 60.0 W
HDSL Line Power On 98.0 W 625.0 W 822.0 W
Maximum Current Drain
HDSL Line Power Off 0.1 A 1.2 A 1.4 A
HDSL Line Power On 1.9 A 11.9 A 15.8 A

SCP-PLL734-020-03H Description and Features
PLL-734 List 2 January 6, 2003 3
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:
•HDSL Noise margin, insertion loss, ES, UAS
•Interface ES and UAS seconds
•Major Alarm Relay Form-C relay contacts (NO, NC, C). Fail-safe operation
Performance Parameters
Based on the monitored parameters, the COLUs derive the following performance parameters:
•MAR A measure of the ratio of signal power to noise power, in decibels (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 “HDSL A
or B Summary Screen” on page 24 and the severity of the alarm at the “System Alarm
Types Screen” on page 40. View the results of these settings at the See “Main
Summary Screen” on page 21.
•LOSW The COLU has 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 A and B Alarm Types Screen” on
page 49. View the results of these settings at the “HDSL A or B Summary Screen” on
page 24.
•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
“HDSL A and B Alarm Thresholds Screen” on page 46, and at the “HDSL A and B
Alarm Types Screen” on page 49 set the severity of the alarm. View the results of these
settings at the “HDSL A or B Summary Screen” on page 24.
•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 “HDSL A and B Alarm Thresholds Screen”
on page 46 and at the “HDSL A and B Alarm Types Screen” on page 49 set the severity
of the alarm. You can view the results of these settings at the “HDSL A or B Summary
Screen” on page 24.
Alarms
The COLUs generate 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 18.
•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.

Description and Features SCP-PLL734-020-03H
4 January 6, 2003 PLL-734 List 2
•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.
•MISPWRnPower supply n is missing (where n is A or B).
•MISMATCHnIncompatible RTnunit has been installed (where n is A or B). For example, a COLU
List 1 has been connected to a 2 ISDN RT.
•NORTSWnRTnhas no application software and is awaiting software download (where n is A or
B).
Alarm Types
At the “System Alarm Types Screen” described on page 40 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 33
•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

SCP-PLL734-020-03H Specifications
PLL-734 List 2 January 6, 2003 5
SPECIFICATIONS
System
Line Interface two-pair, 130 Kbps 2B1Q transmission format
Resistive Signature 162 K Tip to Ground; 453 K Ring to Ground
Power Supply
Input Voltage -42 Vdc to -56.5 Vdc
HDSL Line
Output Voltage + 140 Vdc (maximum)
Output Power 27 W (maximum)
HDSL Line Code 2B1Q
HDSL Line Rate 65.3 K symbols/sec (130 Kbps)
POTS
Analog Impedance 900 Ω
Supported Subscriber Drop 100 Ω plus 430 Ω for handset
COTS Ringer Load 0.9 REN @ 20 Hz (maximum)
COTS Ringer Detection 65 Vrms (minimum) @ 15 to 50 Hz
Compliance
Voltage Safety A2 compliant per GR-1089-CORE
Vibration NEBS
ESD Per GR-1089-CORE
Power and Lightning Per GR-1089-CORE
Human Safety UL 1950 for Restricted Access
Signal Characteristics TR-NWT-001210, Generic Requirements for HDSL Systems
Emissions Radiation and Immunity Per GR-1089-CORE for Class A equipment
Environment
Operating Temperature -40° F to +150° F (-40° C to +65° C)
Operating Humidity 5% to 95% noncondensing
Altitude -60 m to 4,000 m (-200 ft. to 13,000 ft.)
Physical Characteristics
Height 5.5 in. (14.0 cm.)
Width 1.1 in. (2.8 cm.)
Depth 10.3 in. (26.2 cm.)
Weight 1.0 lb. (0.5 kg.)

LED Descriptions SCP-PLL734-020-03H
6 January 6, 2003 PLL-734 List 2
LED DESCRIPTIONS
Table 3 describes the LEDs shown on the front panel, where nequals the POTS line. If you have installed two
RTs then both LED columns light in the manner described.
Figure 2. LED on Front Panel
For further details on the LED activities, refer to “Initialization Sequence” on page 9 and the “COLU and RT Fault
Indicators” on page 64.
All alarms in the PG-Plus application are suppressed when initially installed and powered up. Any alarms that are
generated during this process are suppressed. When the HDSL is synchronized and the COLU and RT margin has
cleared; outstanding alarms that have been suppressed are made active and reported to the PAU or the PMU, based
upon their provisioned types.
Retaining Latc
h
Status LEDs
Active LEDs
LIST
PG-PLUS
PLL-734
PWR
SYNC
BYPASS
POTS1
MARGIN
FAULT
POTS2
AB

SCP-PLL734-020-03H LED Descriptions
PLL-734 List 2 January 6, 2003 7
Table 3. LED Descriptions
LED Color State Description
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 HDSL is in synchronization between COLU and RT.
Flashing COLU and RT are attempting to synchronize.
MARGIN Yellow On COLU margin is below preset value.
Flashing RT margin is below the preset value.
BYPASS Yellow On COLU is in Metallic Fallback, unless provisioned Disable.
On, and POTSn flashing 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.

Required Tools and Test Equipment SCP-PLL734-020-03H
8 January 6, 2003 PLL-734 List 2
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
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.
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.

SCP-PLL734-020-03H Initialization Sequence
PLL-734 List 2 January 6, 2003 9
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 “System History Screen” on page 31.
•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 “System History Screen” on page 31
•The SYNC LED flashes for approximately 6 seconds, then remains off.
•A DSL PFO alarm is indicated on the “System History Screen” on page 31
•The COLU waits 1 minute, then go back to step 3.
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 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.

Subscriber Drop Tests SCP-PLL734-020-03H
10 January 6, 2003 PLL-734 List 2
–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 54):
•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.
It may take up to 4 minutes before end-to-end synchronization is established.