PairGain HiGain HLU-D41 User manual

HIGAIN LINE UNIT
Model List Number Part Number CLEI Code
HLU-D41 2D 150-1260-24 T1L2BE0AAA
PAIRGAIN TECHNOLOGIES, INC.
ENGINEERING SERVICES TECHNICAL PRACTICE
SECTION 150-441-124-01
Revision History of this practice.
June 12, 1997
A) Initial Release

Section 150-441-124 June 12, 1997 Revision 01
Page ii PairGain Engineering - Plant Series HiGain HLU-D41
TABLE OF CONTENTS
A. PRODUCT OVERVIEW................................................................................................................1
1. Description and Features....................................................................................................1
2. Specifications....................................................................................................................3
3. Applications ......................................................................................................................4
4. Functional Operation.........................................................................................................5
5. Power Consumption and Powering the Remote Unit..........................................................6
6. Alarms...............................................................................................................................7
B. INSTALLATION.............................................................................................................................8
7. Inspecting Your Shipment .................................................................................................8
8. HLU-D41 Card Edge Pin-Out Diagram .............................................................................9
9. Installing the HLU-D41....................................................................................................12
10. Connecting to a Dumb Terminal.....................................................................................13
11. Initialization ...................................................................................................................14
C. SETTING OPTIONS FROM THE FRONT PANEL ...................................................................15
12. Using the Mode and Choice Setup Buttons .....................................................................15
13. Mandatory System Options.............................................................................................19
D. SETTING OPTIONS FROM THE MAINTENANCE TERMINAL............................................21
14. Using the Maintenance Terminal Menus.........................................................................21
15. Maintenance Terminal Main Menu.................................................................................22
16. View Span Status............................................................................................................23
17. Set Clock........................................................................................................................26
18. System Settings ..............................................................................................................27
19. Loopback Mode..............................................................................................................30
20. View Performance Data..................................................................................................33
21. View Performance History..............................................................................................34
22. Alarm History.................................................................................................................35
23. Enter Circuit ID..............................................................................................................36
E. TROUBLESHOOTING.................................................................................................................37
24. Loopbacks Issued from the Front Panel...........................................................................37
25. Digital Data Service (DDS) NEI Test Access and Control ..............................................40
F. PRODUCT SUPPORT...................................................................................................................41
26. Technical Support...........................................................................................................41
27. PairGain Warranty..........................................................................................................41
28. Certification....................................................................................................................41
G. ABBREVIATIONS AND GLOSSARY .........................................................................................42
29. Abbreviations and Glossary ............................................................................................42

Revision 01 June 12, 1997 Section 150-441-124
HiGain HLU-D41 PairGain Engineering - Plant Series Page iii
USING THIS TECHNICAL PRACTICE
The following conventions are used in this practice:

Keys that are pressed on the keyboard are enclosed in brackets.
Press the <Enter> key.

Options selected using the front panel Mode and Choice Setup buttons and the Maintenance Terminal
menus are italicized.
The Network Loopback option can be set to Enable or Disable.

Fields are identified with quote marks.
Table 14 lists the "Alarm" messages and descriptions.
Three types of messages, identified by icons, appear in the text:
A note informs you of special circumstances.
A caution indicates the possibility of equipment damage.
A warning indicates the possibility of personal injury.

Copyright 1997 PairGain Technologies, Inc.
PairGain is a registered trademark, and HiGain is a trademark of PairGain Technologies, Inc.

Revision 01 June 12, 1997 Section 150-441-124
HiGain HLU-D41 PairGain Engineering - Plant Series Page 1
A. PRODUCT OVERVIEW
1. Description and Features
1.1 This technical practice describes the PairGain
®
HiGain  HLU-D41 List 2D, a HiGain Line Unit
(HLU) which functions as the Central Office (CO) side of a repeater-less Fractional T1 (FT1)
transmission system. The HLU-D41 can be plugged into a channel unit slot of a D4 channel bank or
an SLC-96 channel bank. This practice describes using the HLU-D41 with and without HiGain
Doubler Units (HDUs). The software version number for this release is 2.3.
1.2 Figure 1 shows a basic HiGain configuration for an FT1 Single-pair High-bit-rate Digital Subscriber
Line (S-HDSL) circuit. The HLU-D41 is installed at the CO channel bank and the HRU-512 is
housed in a remote enclosure at the Customer Premises Equipment (CPE) site. The optional
HDU-217 or HDU-219 installed in a doubler enclosure provides the ability to double or even triple
the transmission distance range for customer applications located outside the Carrier Service Area
(CSA). The CSA includes loops up to 12000 feet of AWG 24 or 9000 feet of AWG 26 wire,
including bridged taps.
Figure 1. Typical HiGain S-HDSL System
1.3 HLU-D41 List 2D features

Selectable payload bandwidth from 64 kbps (one channel) to 768 kbps (12 channels) in 64 kbps
increments over the full CSA

Front panel:
– DS1 splitting and bridging access
– Status LEDs and user option setup buttons
– LCD display of HDSL margin, configuration parameters, and alarms

Automatic front panel display power saving timer

RS-232 connector for setting options from the Maintenance Terminal

Responds to Digital Data Service (DDS), Network Element Interface (NEI), and Office Channel
Unit (OCU) loopback codes

Provisionable idle code (7F or FF) on unused channels

Lightning and power cross protection on S-HDSL interface

200V power feed can line power two spans (one doubler and one remote, or two doublers and a
locally-powered remote)

Section 150-441-124 June 12, 1997 Revision 01
Page 2 PairGain Engineering - Plant Series HiGain HLU-D41
1.4 Front Panel. Figure 2 and Table 1 describe the HLU-D41 front panel. The four-digit LCD and the
status LEDs indicate different system states.
Figure 2. HLU-D41 Front Panel
Table 1. HLU-D41 Front Panel Components
Name Function
Four-digit LCD Shows HDSL conditions, s
y
stem o
p
tions, messa
g
es and alarm states (see Section 12).
Alarm messages are listed in Section 6.
Mode and Choice Setu
p
buttons Set system options (see Section 12).
DDS test access jacks Bantam jacks designated as Logic Out and Logic In for high-speed DDS test access.
Status LED Indicates status, warnings, and alarm conditions (see Table 2).
RS-232 connector Confi
g
ured as Data Circuit-Terminatin
g
E
q
ui
p
ment (DCE) which allows
y
ou to control
the HLU-D41 through a dumb terminal (or a PC with terminal emulation software).
Retaining latch Latch used to retain the HLU-D41 in the channel bank.

Revision 01 June 12, 1997 Section 150-441-124
HiGain HLU-D41 PairGain Engineering - Plant Series Page 3
Table 2. Status LED Messages
Color Definition
Green Normal operation
Flashing Green HDSL acquisition
Red Fuse Alarm
Flashing Red Minor alarm (For conditions see Section 6.1, Table 5).
Yellow Self-test in
p
rocess or a Customer Remote (CREM) or
Network Local (NLOC) loopback is in effect.
2. Specifications
S-HDSL
Line Code ..........................................................768 kbps 2B1Q
Output................................................................+13.5 dB ±0.5 dB at 135 ohms
Line Impedance .................................................135 ohms
Start-up Time.....................................................30 seconds (typical), 60 seconds (maximum) per span
Span Voltage......................................................-200 Vdc
Compliance........................................................TA-TSY-001210
Maximum Provisioning Loss
35 dB at 196 kHz, 135 ohms
Line Clock Rate
Internal Stratum 4 clock
Maximum Power Consumption
Without doubler.................................................10 W
With doubler......................................................14 W
Maximum Heat Dissipation
Without doubler.................................................3 W
With doubler......................................................6 W
Electrical Protection
Secondary surge protection on DS1 and HDSL ports. Power cross protection on HDSL ports.
Environmental
Operating Temperature ......................................-40°to +149°F (-40°to +65°C)
Operating Humidity ...........................................5 to 95% (non-condensing)
Mounting
Single channel unit slot of a D4 or SLC-96 channel bank.
DS1Line Rate ...........................................................1.544 Mbps ±200 bps
Line Format .......................................................AMI, B8ZS or ZBTSI
Frame Format.....................................................ESF or SF

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Dimensions
Height................................................................4.5-inch (11.4 cm)
Width ................................................................1.4-inch (3.6 cm)
Depth.................................................................10.1-inch (25.7 cm)
Weight...............................................................0.7 lb. (.32 kg)
Margin Indicator
Displays HDSL span Signal-to-Noise Ratio (SNR) margin relative to 10-7 Bit Error Ratio (BER) operation
3. Applications
3.1 This HiGain system provides a cost-effective, easy-to-deploy method for delivering FT1 service over
a single metallic pair. Conventional in-line T1 repeaters are not required. Cable pair conditioning,
pair separation and bridged tap removal are not required.
3.2 General guidelines require that the loop has less than 35 dB of loss at 196 kHz, with 135 ohms
driving and terminating impedances. Table 3 provides a guide for the loss of various cable gauges at
196 kHz and 135 ohms. The table applies to the HDSL cable pairs between the HLU, HRU and
HDU modules. Without specific insertion loss measurement data, add 3 dB for each bridged tap and
1 dB for each cable gauge change.
Table 3. HDSL Loss Over Cables
Cable Gauge Loss at 196 kHz
(dB/kft) Ohms per kft
26/0.4 mm 3.88 83
24/0.51 mm 2.84 52
22/0.61 mm 2.18 32
19/0.91 mm 1.54 16
3.3 HiGain systems:

Operate with any number of other T1, Plain Old Telephone Service (POTS), DDS or other
HiGain systems sharing the same cable binder group.

Can be used with customers requiring FT1 service on a temporary or permanent basis.

Provide a means of quickly deploying service in advance of fiber-optic transmission systems.

Are easily installed allowing service to be provided within hours. Fiber optic systems can be
installed at a leisurely pace and cut-over from the installed HiGain system when convenient to
do so. The installed HiGain system can then be easily removed and utilized elsewhere.

Revision 01 June 12, 1997 Section 150-441-124
HiGain HLU-D41 PairGain Engineering - Plant Series Page 5
4. Functional Operation
4.1 The HLU-D41 block diagram is shown in Figure 3.
Figure 3. HLU-D41 Block Diagram
The HLU-D41 uses one PairGain Technologies 2B1Q HDSL transceiver to establish a full duplex
784 kbps data link to the remote unit in the following sequence:
1Multiplexed DS0 channels are extracted from the channel bank backplane. The number of
channels extracted is determined by the BAND option setting using the front panel Mode and
Choice Setup buttons, or the DS0 BANDWIDTH option using the Maintenance Terminal menus.
2The DS0 channels optioned for A/B Robbed Bit Signaling (RBS) are properly formatted, then
the DS0 channels are passed to the DS1 formatter which builds a DS1 signal.
3The formatter inserts DS1 framing information and generates the Idle Code (7F or FF) to
complete a 12 DS0 payload for the half-DS1 signal, then the half-DS1 signal is passed to the
HDSL framer.
4The framer bit stuffs the half-DS1 signal into the HDSL payload envelope and adds the required
HDSL overhead.
5The 784 kbps HDSL signal is encoded by the single pair transceiver into a 2B1Q signal.
6The 2B1Q signal is coupled to the twisted pair line by a transformer in the line interface, which
allows the line interface to provide lightning and power cross protection.
7The 784 kbps signal from the remote HDSL transceiver is received by the HDSL line interface.
8The single pair transceiver does a two-wire to four-wire conversion of the signal using echo-
canceling technology, then the signal to be transmitted toward the channel bank is processed by
the HDSL framer which monitors its signal quality.
9Detected errors are reported to the micro-processor, the payload is extracted, and up to 12 DS0
channels are transmitted to the channel bank, with the DS1 formatter locating the first DS0 in

Section 150-441-124 June 12, 1997 Revision 01
Page 6 PairGain Engineering - Plant Series HiGain HLU-D41
the payload. An 8-bit microprocessor is used to monitor and control the HLU-D41.
Provisioning status information is provided either through the HLU-D41 Maintenance Terminal
menus or the front panel Mode and Choice Setup buttons, to the microprocessor. The micro-
processor communicates with the HDSL framer for signal status and configures the circuit
bandwidth at the DS0 channel interface.
5. Power Consumption and Powering the Remote Unit
5.1 The primary power demands of an HLU-D41 on the channel bank power supply are listed in Table 4
on a per slot basis.
Table 4. Power Consumption and Power Dissipation
Power* Per Slot
Maximum Power Consumption
Line-powered remote unit 14 W
Locally-powered remote unit 10 W
Maximum Power Dissipation
Line-powered remote unit 6 W
Locally-powered remote unit 3 W
The worst case conditions under which these parameters are
measured include a 9,000 ft., 26 AWG loop configuration.
5.2 The maximum number of channel bank slots that can be occupied by HLU-D41 units is a function of
the type of bank and the capabilities of its common power supply. The limiting factor is the drain on
the bank’s +5V power supply. The HLU-D41 draws 295mA of +5V power when the HRU is locally
powered and 325mA when the HRU is line powered. The worst case +5V current drain for D4
common equipment is 1.2A.
5.3 Line and Local Powering of the Remote Unit. The HLU-D41 is designed to either power the
HRU-512 over the HDSL cable pair, or allow the HRU-512 to be powered from the remote end. The
HLU-D41 determines the power state of the HRU-512 before attempting to apply line power:

If the HRU-512 is remotely powered, the HLU-D41 does not apply line power.

If the HRU-512 is not remotely powered, the HLU-D41 applies power to the HRU-512 over the
HDSL cable pair.
The line power supply can be turned on or off by using the PWRF (power feed) system option setting
and is automatically shut down in the presence of line short circuits or a microprocessor failure.
The HRU-512 also provides from 14 mA (long loop) to 16 mA (short loop) of metallic sealing
current toward the HLU-D41, when the HRU-512 is locally powered. To enable the sealing current
capability when the HRU-512 is locally powered, connect JP2 across both terminals.
To configure the system for HLU-D41 line powering
1At the HRU-512, connect JP2 across just one of the two terminals. These are the factory default
settings.
2Enable the PWRF option setting using the front panel setup buttons, or the Maintenance
Terminal menus using the POWER option in the System Settings menu.