PairGain T1L2N20A User manual

HIGAIN LINE UNIT
PAIRGAIN TECHNOLOGIES, INC.
ENGINEERING SERVICES TECHNICAL PRACTICE
SECTION 150-388-151-01
Model List Number Part Number CLEI Code
HLU-388 5A 150-1141-51 T1L2N20A
MODE SEL
M
A
R
G
I
N
(dB)
SETUP
STATUS
RS
232
DCE
HLU 388
HG HDIAIN
L5A

150-388-151-01, Revision 01
ii September 15, 1999 HLU-388 List 5A
Revision History of This Practice
© Copyright 1999 PairGain Technologies, Inc.
PairGain andHiGain areregistered trademarks of PairGain Technologies, Inc. All other product namesmentionedin this practice
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 toPairGain Technologies, Inc., and shall not be modified, used, copied,
reproduced or disclosed in whole or in part without the written consent of PairGain.
Information furnished by PairGain Technologies is believed to be accurate and reliable. However, no responsibility is assumed by
PairGain Technologies for its use, nor for any infringement of patents or other rights of third parties which may result from its use.
No license is granted by implication or otherwise under any patent or patent rights of PairGain Technologies. PairGain
Technologies reserves the right to change specifications at any time without notice.
Revision Release Date Revisions Made
01 September 15, 1999 Initial release

150-388-151-01, Revision 01 Using This Technical Practice
HLU-388 List 5A September 15, 1999 iii
USING THIS TECHNICAL PRACTICE
The following conventions are used in this manual:
•Monospace type indicates screen text, including text you type at a screen prompt.
•Keys you press are indicated by small icons such as . Key combinations to be pressed simultaneously
are indicated with a plus sign as follows: + .
•Three types of messages, identified by icons, appear in text.
For a list of abbreviations used in this document, refer to “Appendix D - Glossary” on page 66.
DOCUMENTATION
If you have comments on this PairGain document, send an email to [e-mail]. Type
the product name and the section number of the document in the subject area of the email message.
INSPECTING THE SHIPMENT
Upon receipt of the equipment:
•Unpack each container and 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 PairGain. 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 PairGain as described in the Warranty located inside the back cover. If you must store
the equipment for a prolonged period, store the equipment in its original container.
Notes contain information about special circumstances.
Cautions indicate the possibility of equipment damage or personal injury.
The Electrostatic Discharge (ESD) Susceptibility symbol indicates that a device or assembly is
susceptible to damage from electrostatic discharge.
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Table of Contents 150-388-151-01, Revision 01
iv September 15, 1999 HLU-388 List 5A
TABLE OF CONTENTS
Overview ____________________________________________________________________________ 1
Features.............................................................................................................................................. 1
Product Enhancements........................................................................................................ 1
Standard Features................................................................................................................ 1
Compatibility..................................................................................................................................... 2
Applications....................................................................................................................................... 2
HiGain Doubler Applications ............................................................................................. 3
Personal Communications System Applications ................................................................ 3
Front Panel __________________________________________________________________________ 4
Installation___________________________________________________________________________ 8
Verification........................................................................................................................................ 9
Verification without a Downstream Device........................................................................ 9
Verification with a Downstream Device............................................................................. 9
Provisioning Requirements ............................................................................................................. 10
Provisioning_________________________________________________________________________ 11
Using the MODE and SEL Buttons................................................................................................. 11
Setting Options through MODE and SEL......................................................................... 11
Resetting to Factory Default Values................................................................................. 12
Displaying System Parameter Settings ............................................................................. 12
Disabling an Alarm........................................................................................................... 12
Loopback Modes............................................................................................................... 12
Using a Maintenance Terminal ....................................................................................................... 13
Connecting to a Maintenance Terminal............................................................................ 13
Accessing the Maintenance Terminal Screens.................................................................. 14
Using the Maintenance Terminal Screens....................................................................................... 16
View Span Status Screen .................................................................................................. 16
Set Clock Screen............................................................................................................... 21
System Settings Screen..................................................................................................... 22
Loopback Mode Screen .................................................................................................... 28
View Performance Data Screen........................................................................................ 31
View Performance History Screen.................................................................................... 33
View Alarm History Screen.............................................................................................. 35
System Inventory Screen .................................................................................................. 37
View Troubleshooting Screen........................................................................................... 39

150-388-151-01, Revision 01 Table of Contents
HLU-388 List 5A September 15, 1999 v
Troubleshooting _____________________________________________________________________ 43
System Alarms.................................................................................................................................43
Alarm Option for DLC Feed .............................................................................................44
Retiring System Alarms.....................................................................................................44
Self Test.............................................................................................................................44
Loopback Operation.........................................................................................................................45
Generic Loopback Commands ..........................................................................................45
Special Loopback Commands ...........................................................................................47
Manual Loopback Session.................................................................................................48
Loopback Test Procedures...............................................................................................................49
General Troubleshooting Tips...........................................................................................49
GNLB Test Procedures......................................................................................................49
A1LB, A2LB, and A5LB Test Procedures........................................................................51
A3LB and A4LB Test Procedures.....................................................................................54
Appendix A - Specifications____________________________________________________________ 55
HDSL Insertion Loss Guidelines.....................................................................................................56
Power Consumption.........................................................................................................................56
Power Consumption without Doublers..............................................................................56
Power Consumption with Doublers...................................................................................57
Maximum Power Dissipation...........................................................................................................59
Maximum Current Drain..................................................................................................................59
HLU-388 List 5A Card Connector...................................................................................................60
Network Management Control Bus...................................................................................60
Fuse Alarm ........................................................................................................................60
Craft Port..........................................................................................................................................61
Appendix B - Functional Operation _____________________________________________________ 62
Timing..............................................................................................................................................62
Ground Fault Detect.........................................................................................................................62
Appendix C - Compatibility ___________________________________________________________ 64
T1 Repeater Shelves and Related Equipment..................................................................................64
HiGain Doubler Circuit Deployment...............................................................................................64
Appendix D - Glossary________________________________________________________________ 66
Appendix E - Product Support _________________________________________________________ 68
Technical Support............................................................................................................................68
World Wide Web.............................................................................................................................68
Returns.............................................................................................................................................68
Certification and Warranty______________________________________________ Inside Back Cover

List of Figures 150-388-151-01, Revision 01
vi September 15, 1999 HLU-388 List 5A
LIST OF FIGURES
1. HLU-388 List 5A Front Panel ........................................................................................................................ 4
2. Installing the HLU-388 List 5A into a Shelf .................................................................................................. 8
3. Maintenance Terminal Main Menu .............................................................................................................. 15
4. System Spans................................................................................................................................................ 16
5. Span Status Screen: No Doubler................................................................................................................... 17
6. Span Status Screen: Four Doublers (Span 5)................................................................................................ 18
7. Set Clock Screen........................................................................................................................................... 21
8. System Settings Screen................................................................................................................................. 22
9. Loopback Menu: No Doubler....................................................................................................................... 29
10. Loopback Menu: Four Doublers................................................................................................................... 29
11. NLOC Loopback Mode Reported in the Maintenance Terminal Main Menu.............................................. 30
12. Performance Data Screen: No Doubler......................................................................................................... 32
13. Performance Data Screen: Four Doublers (Span 5)...................................................................................... 32
14. 31-Day Performance History Screen: No Doubler....................................................................................... 33
15. 31-Day Performance History Screen: Four Doublers (Span 5).................................................................... 34
16. Alarm History Screen: No Doubler .............................................................................................................. 36
17. Alarm History Screen: Four Doublers (Span 5) ........................................................................................... 36
18. System Inventory Screen: No Doubler......................................................................................................... 38
19. System Inventory Screen: Four Doublers..................................................................................................... 38
20. Troubleshooting Screen for a Doubler Application...................................................................................... 39
21. Troubleshooting Screen Describing Circuit Problem................................................................................... 39
22. Troubleshooting with Help........................................................................................................................... 40
23. Troubleshooting with Margin Values........................................................................................................... 41
24. Troubleshooting with Insertion Loss Values................................................................................................ 41
25. Troubleshooting with 24 Hour Errored Seconds (ES).................................................................................. 42
26. Troubleshooting with 24 Hour Unavailable Seconds (UAS) ....................................................................... 42
27. Loopback Summary...................................................................................................................................... 45
28. Loopback Configurations ............................................................................................................................. 50
29. HLU-388 List 5A Card-edge Connector ...................................................................................................... 60
30. RS-232 Craft Port Pinouts ............................................................................................................................ 61
31. HLU-388 List 5A Block Diagram ................................................................................................................ 62

150-388-151-01, Revision 01 List of Tables
HLU-388 List 5A September 15, 1999 vii
LIST OF TABLES
1.HDSL Loss Over Cables..................................................................................................................................2
2.Front-panel Description....................................................................................................................................5
3.Front-Panel Display Messages.........................................................................................................................6
4.Navigational Keys on the Maintenance Terminal..........................................................................................14
5.Maintenance Terminal Screens ......................................................................................................................15
6.Span Status Fields and Descriptions...............................................................................................................19
7.HDSL System Alarms....................................................................................................................................20
8.Loopback Messages........................................................................................................................................20
9.HLU-388 List 5A System Settings.................................................................................................................23
10.Loopback Field Messages and Descriptions ..................................................................................................28
11.Errored and Unavailable Seconds Definitions ...............................................................................................31
12.Alarm History Fields and Descriptions..........................................................................................................35
13.HDSL System Alarms....................................................................................................................................43
14.Summary of HiGain Loopback Codes ...........................................................................................................46
15.Addressable Repeater Loopback Commands (A1LB, A2LB, A5LB) ...........................................................51
16.Addressable Repeater Loopback Commands (A3LB and A4LB) .................................................................54
17.HDSL Loss Over Cables................................................................................................................................56
18.HLU-388 Power Parameters—No Doubler....................................................................................................56
19. HLU-388 Power Parameters—Single Doubler (HDU-451 List 1 or 2)........................................................57
20.HLU-388 Power Parameters—Single Doubler (HDU-439 or HDU-437 Lists 1 and 1B).............................57
21.HLU-388 Power Parameters—Single Doubler (HDU-409 List 2, HDU 407 List 2,
and HDU-404 List 2)...............................................................................................................................57
22.HLU-388 Power Parameters—Two Doublers (HDU-451 List 3, 4, 3B or 4B).............................................58
23.HLU-388 Power Parameters—Two Doublers (HDU-439 or HDU-437 Lists 1 and 1B) ..............................58
24.HLU-388 Power Parameters—Two Doublers (HDU-409 List 2, HDU-407 List 2,
and HDU-404 List 2)...............................................................................................................................58
25.HLU-388 Power Parameters—Three and Four Doublers (HDU-409 List 2, HDU-407 List 2,
and HDU-404 List 2)...............................................................................................................................58
26.HiGain Doubler Deployment Matrix..............................................................................................................65

List of Tables 150-388-151-01, Revision 01
viii September 15, 1999 HLU-388 List 5A

150-388-151-01, Revision 01 Overview
HLU-388 List 5A September 15, 1999 1
OVERVIEW
The PairGain®HiGain®Line Unit HLU-388 List 5A is the Central Office (CO) side of a repeaterless
T1 transmission system. When used in conjunction with a HiGain Remote Unit (HRU), the system provides
1.544 Mbps transmission on two unconditioned copper pairs over the full Carrier Service Area (CSA) range. The
CSA includes loops up to 12,000 feet of24 AWG or 9,000 feet of 26 AWG wire, including bridged taps. This line
unit can be used with HiGain Doubler Units (HDUs) to extend reach.
FEATURES
Product Enhancements
•Fast Loss of Sync Word (LOSW) reporting
•Five-span range with four doublers (60 kft, 24 AWG)
•Four line-powered spans (three doublers and one remote)
•Reduced power consumption
•Ultra-low wander (Stratum 1 compliant)
•Low line-power option setting (-140 Vdc) for circuits with a single doubler
•Selectable Power Feed (PWRF) modes: Auto, High, and Low
•Grounded loop detection on High-bit-rate Digital Subscriber Line (HDSL)
•Bipolar Violation Transparency (BPVT) options
•Bit Error Rate (BER) alarm options
•HRU loopback screen
•Inventory Screen (displays Circuit ID and unit IDs)
•Loss of Signal/Alarm Indicator Signal (LOS/AIS) payload alarm option
•Remote Loss of Signal (RLOS) disable alarm option
•Supports HRU-411 in Personal Communications System (PCS) applications
•Improved performance for AUTO DS1 line code mode
•Default setting screen option
•Payload (PL) or HiGain (HG) loopback source identification
•Troubleshooting screen
Standard Features
•Selectable DS1 pre-equalizer
•Front-panel features:
–Four-character status display
–Status Light Emitting Diode (LED)
–RS-232 craft port (via 210 jack) for connection to a maintenance terminal (ASCII terminal or a PC
running a terminal emulation program)

Overview 150-388-151-01, Revision 01
2 September 15, 1999 HLU-388 List 5A
•Compatible with Double Dual Module Plus (DDM+) high-density shelves
•Selectable loopback activation codes
•Network Management and Administration (NMA) interface
•Lightning and power cross protection on HDSL interfaces
•Full duplex 2B1Q HDSL transmission on two pairs at 784 kbps
•Margin threshold alarm
COMPATIBILITY
The HLU-388 List 5A is designed to mount in DDM+ T1 repeater shelves. For a list of compatible shelves, see
“Appendix C - Compatibility” on page 64.
All generations of HiGain HLU and HRU modules are compatible with each other. To take advantage of the
enhanced features of newer HiGain doublers, refer to “HiGain Doubler Circuit Deployment” on page 64.
APPLICATIONS
HiGain systems provide a cost-effective, easy-to-deploy method for delivering T1 High Capacity Digital Service
(HCDS) over metallic pairs.
•The service is deployed over two unconditioned, non-loaded copper pairs, yet it demonstrates a quality that
is competitive with fiber optics.
•Conventional, in-line, T1 repeaters are not required.
•Cable pair conditioning, pair separation, and bridged tap removal are not required.
Each loop has no more than 35 dB of loss at 196 kHz, with driving and terminating impedances of 135 Ω.
Table 1 provides a loss guide for the various cable gauges at 196 kHz and 135 Ω. The table applies to the HDSL
cable pairs between the HLU, HRU, and HDU modules. In the absence of specific insertion loss measurement
data, add 3 dB for each bridged tap and 1 dB for each cable gauge change.
Table 1. HDSL Loss Over Cables
Cable Gauge (AWG/mm) Loop Loss at
196 kHz (dB/kft)
Loop Resistance
(Ωper kft)
26 / 0.4 3.88 83
24 / 0.51 2.84 52
22 / 0.61 2.18 32
19 / 0.91 1.54 16