ADTRAN | List 3 ISDN 2B1 | Installation and Maintenance | Adtran List 3 ISDN 2B1 Installation and Maintenance

Adtran List 3 ISDN 2B1 Installation and Maintenance
Section 61153017L3-5, Issue 1
PRACTICES
C A U T I O N !
SUBJECT TO ELECTROSTATIC DAMAGE
OR DECREASE IN RELIABILITY.
Section 61153017L3-5
Issue 1, April 1995
List 3: CLEI # DDRPED9_ _ _
HANDLING PRECAUTIONS REQUIRED.
MODEL U-REPEATER III, LIST 3
ISDN 2B1Q REPEATER
INSTALLATION AND MAINTENANCE
1.
2.
3.
4.
5.
6.
CONTENTS
GENERAL ........................................................................... 1
INSTALLATION ................................................................ 2
CIRCUIT TURN UP ........................................................... 3
MAINTENANCE ................................................................ 4
DEPLOYMENT GUIDELINES ......................................... 5
WARRANTY AND CUSTOMER SERVICE ................... 5
FIGURES
Figure 1. U-Repeater III Circuit Pack ......................................... 1
Figure 2. Mounting the U-Repeater IIIwith the Dual
Lock Fastener System .................................................. 3
Figure 3. Loop Sync Indicator ..................................................... 3
Figure 4. Typical U-Repeater III Circuit Voltage
Test Points .................................................................... 4
Figure 5. ISDN U-Repeater III (Third Generation)
Mixed Gauge Deployment Chart ................................. 6
TABLES
Table A. Basic Features ............................................................... 2
Table B. Equipment Options for the U-Repeater III System ..... 2
Table C. LED Indication Descriptions ........................................ 3
1.
GENERAL
1.1
This practice provides installation and
maintenance procedures for the ADTRAN ISDN URepeater III. The circuit pack is shown in Figure 1.
Table A provides the part number and the basic feaures
of the unit. Table B provides the part numbers and lists
the basic features of the equipment option for the URepeater III system.
1.2
This is the first issue of this practice.
1.3
The ADTRAN U-Repeater III is a device for
extending the ISDN Basic Rate Interface (BRI). It is
capable of operating up to 42 dB loop loss at 40 KHz with
6 dB ANSI Near End Cross Talk (NEXT) Margin. This
allows up to 1300 Ω DC resistance on both the network
side and customer side loops.
Note: This module is to be used with ADTRAN URepeater II Power Module, part number
1212017L1, L2 (T400) or 1102009L1 (D4) only.
1.4
The ADTRAN U-Repeater III provides a means
of extending the digital subscriber loop serving range up
to 32 kFt of 26-gauge twisted pair wire/cable using a 2600
Ω total loop resistance design with a centrally located
repeater. The unit has no manual option settings.
1.5
Power to operate the U-Repeater III is derived
from a 43 mA constant sealing current source,
independent of line impedance or wire gauge provided by
an ADTRAN U-RPM II located in the Central Office (CO).
The repeater uses 36 mA of the current and passes 5 mA
to 7 mA of sealing current to the customer NT1.
Figure 1. U-Repeater III Circuit Pack
61153.017L3-5A
Page 1
Section 61153017L3-5, Issue 1
Table A. Basic Features
Unit
Part No.
U-Repeater 1153017L3
III List 3
Features
Provides an ISDN U-interface
toward the network and toward
the customer according to ANSI
T1.601-1992.
Provides both interim path and
segmented performance monitoring, per TR-NWT-000397.
Provides eight hours of performance monitoring history per TRNWT-00829.
Responds to the eight ISDN BRA
National Standard eoc messages.
Provides lightning and power
cross protection required by TRNWT-001089.
Derives operating power from the
network-side wire pair, requiring
43 mA constant current at 28 V to
the repeater, while supplying 5
mA to 7 mA of sealing current
toward the customer.
Provides termination signal to
NT1 when power is applied and a
constant sealing current.
1.7
This U-Repeater does not require mounting in a
repeater apparatus case. Becaue it is encapsulated in a
polyurethane compound, this device is weatherproof
and can be mounted on a pole, in a pedestal, in a
manhole, or other suitable location.
1.8
The U-Repeater III L3 interchanges with the
ADTRAN U-Repeater II (1152017L3), but does not
interchange with U-Repeater (1150017L1/L2/L3).
2.
INSTALLATION
2.1
Dual Lock Mounting Option
The ISDN U-Repeater III can be mounted using
bolts, tie wraps, or ADTRAN-supplied dual lock fasteners.
Figure 2 shows how to mount the ISDN U-Repeater III
with dual lock fasteners.
2.2
Remove the repeater circuit pack from the carton
and visually ensure that damage has not occurred during
shipping or handling. If damage has occurred, file a claim
immediately with the carrier, then contact ADTRAN
customer service; see Subsection 6.2.
1.6
The U-Repeater III operates at line losses up to
42 dB at 40 kHz with 6 dB of ANSI NEXT Margin, in both
directions from the repeater and regenerates the 2B1Q
signals to meet the transmitted power spectrum of ANSI
T1.601-1992.
Table B. Equipment Options for the U-Repeater III System
Unit
Part Number
CLEI
Number
Features
U-Repeater III L3 Circuit Pack
(Encapsulated)
1153017L3
DDRPED9_ _ _ Single repeater unit; uses 2B1Q line coding; range
up to 16 kFt of 26-gauge wire each direction from
repeater; lightning protection; eoc loopback; crc
test modes; elastic data buffers for jitter control.
U-Repeater II Powering Module-D4
T400 -48 VDC
T400 -72 VDC
1102009L1
1212017L1
1212017L2
DDRPGH6_ _ _ Provides constant 43 mA down signal pair to power
DDRPHH6_ _ _ one repeater, allows for passive customer data
DDRPHB6_ _ _ flow, monitors the line for excessive resistance or
open loop, standard D4 or T400 size plug-in.
U-Repeater Powering Shelf (GPC L3)
1150001L3
D4MEE30_ _ _ Single height shelf accommodates up to 12 D4 URPM IIs, fused -48 V alarm output, connectorized
input/output.
T400-19 Shelf
1150028L1
NDMMAA0_ _ _ 19" Rackmount shelf houses up to 12 U-RPM T400
circuit packs.
NT1 T400-23 Shelf, Rackmount
1150024L1
NDMMBA0_ _ _ 23" Rackmount shelf houses up to 12 U-RPM T400
circuit packs.
NT1 T400-23 Enclosed Wallmount
Shelf
1150024L2
Page 2
N/A
23" Wallmount shelf houses up to 12 U-RPM T400
circuit packs.
Section 61153017L3-5, Issue 1
Required:
Two Type 400 2-inch plastic strips
(dense stem pattern)
Two Type 170 plastic strips
Clean, dry mounting surface
1. Remove green protective strips from Type 400 Velcro®
strips and press into place, approximately 1⁄4-inch
from each end of the housing as shown below.
2. Secure Type 170 strips to Type 400 strips (Velcro -toVelcro), then remove green protective strip.
3. Carefully align housing into mounting position, press
firmly into place, and hold for 30 seconds.
2.4
Make sure that the U-RPM power module is
removed while making punch-down connections to the
U-Repeater III. Connect the network side of the URepeater III by punch-down connection to the bluewhite/white-blue pair. Connect the customer side of the
repeater by punch-down connection to the orange-white/
white-orange pair. Connect the 10-AWG ground wire on
the U-Repeater III to a suitable earth ground connection.
OPTIONING THE U-REPEATER III
2.5
The repeater circuit pack has no option settings.
Note:
3.
Only one repeater may be used in an
ISDN Basic Rate local loop.
CIRCUIT TURN UP
3.1
A green LED at the rear of the unit is provided to
aid in circuit turn up and diagnostics (see Figure 3). The
indications provided by this LED are described in Table C.
BOTTOM
Indication
Figure 2. Mounting the U-Repeater III
with the Dual Lock Fastener System
2.3
Select a suitable site or pole along the main
cable where a loop loss up to 42 dB at 40 kHz is
measured from the U-LT to the repeater.
The loop loss from the repeater to the customer
site should not exceed 42 dB at 40 kHz, unless a bit error
rate (BER) measurement is performed to ensure a
maximum BER of less than 1x10-7.
Meaning
LED Flashes three
times after applying
power.
Unit receiving power, self test
passed.
LED Flashes once per
second.
U-interface synchronized to
network.
LED On solid.
U-interface synchronized on
network and customer sides.
Table C. LED Indication Descriptions
Figure 3. Loop Sync Indicator
Velcro is a registered trademark of Velcro BV.
Page 3
Section 61153017L3-5, Issue 1
3.2
The LOOP SYNC indicator at the end away from
where the cable enters the unit Flashes green three
times to indicate when the unit receives power from the
U-RPM and passes a power-on self test. Failure of this
indication may be due to incorrect or shorted wiring,
either at the MDF between the LT and the U-RPM or
between the U-RPM and the U-Repeater III. These
conditions must be cleared before circuit turn up may
proceed.
3.3
After verifying that the unit is receiving power from
the U-RPM, the next step is to verify loop synchronization
between the LT and the U-Repeater III. Once the network
side of the unit has achieved synchronization to the LT, the
LOOP SYNC indicator Flashes once per second. Failure
of the unit to synchronize to the LT may be caused by a bad
or incorrect line card, loop loss in excess of 42 dB @ 40 kHz,
or excessive noise on the loop. These conditions must be
cleared before proceeding.
4.
MAINTENANCE
4.1
The U-Repeater III requires no routine
maintenance to operate. In case of equipment
malfunction, advise the CO to perform an mp-eoc
loopback test, per TR-NWT-000397. If a malfunction is
confirmed, replace the U-Repeater III circuit pack; see
subsection 6.3.
4.2
The repeater has looping capability (B1,B2, and
2B+D) through the maintenance channel which allows
for digital loopback, per TR-NWT-000397 to aid in fault
isolation. The looping is accomplished remotely from the
CO switch or from the ADTRAN U-BR1TE channel unit.
In addition, eight hours of performance history is available
to the network as described in TR-NWT-000829. This
performance history may be used for troubleshooting
and fault isolation purposes.
REPLACEMENT OF CIRCUIT PACKS
3.4
After the unit has achieved synchronization to
the network, synchronization to the customer may be
verified if the customer’s NT1 is installed. Once the URepeater III synchronizes to the customer NT1, the
LOOP SYNC indicator remains On. This indicates that
a Layer 1 connection between the LT and the customer
NT1 has been established. Failure of the unit to
synchronize to a properly installed NT1 may indicate
excessive loop loss, noise, or faulty wiring.
4.3
Remove the U-RPM associated with this circuit
at the CO.
4.4
Replace the faulty circuit pack.
4.5
Insert the U-RPM and verify loop synchronization
of the U-Repeater III.
4.6
Advise the CO to perform an mp-eoc loopback
test, per TR-NWT-000397.
4.7
ADTRAN recommends that no repairs to the
circuit pack be performed in the field. Repair services
maybe obtained by returning a defective unit to the
ADTRAN Repair Department.
LT
U-INTERFACE
MAIN
DISTRIBUTION
U-REPEATER
FRAME
POWERING MODULE
MDF
NT1
U-REPEATER III
U-RPM
AA
CC
B
B
- +
CURRENT
SOURCE
REPEATER
POWER
CONVERTER
TERMINATION
Loop resistance fault indicator on U-RPM II Flashes continuously or
* remains
On when loop resistance is too high or the circuit is open.
Figure 4. Typical U-Repeater III Circuit Voltage Test Points
Page 4
Section 61153017L3-5, Issue 1
TESTING THE REPEATER AT THE CENTRAL
OFFICE
4.8
The ADTRAN U-Repeater III performs the
standard mp-eoc loopbacks described in TR-NWT000397.
TYPICAL VOLTAGE MEASUREMENTS (NORMAL
OPERATING CONDITION)
4.9
Figure 4 shows a typical loop originating at the
LT U-Interface and terminating at the customer NT1.
Use a digital multimeter to measure across the loop as
demonstrated in the illustration.
The test points (A, B, and C) should contain the
following voltage readings under normal operating
conditions.
A. 28 VDC to 120 VDC. Actual voltage equals 28 V plus
the line voltage drop between the U-RPM and the URepeater III.
B. 28 VDC + -3 V.
C. 1. Not terminated at NT1 = 28 V ± 3 V.
2. Terminated at NT1 = 6 to 12 V.
5.
6.
WARRANTY AND CUSTOMER SERVICE
ADTRAN will replace or repair this product within
five years from the date of shipment, if the product does
not meet its published specifications or if it fails while in
service. For detailed warranty, repair, and return
information, refer to the ADTRAN Equipment Warranty
and Repair and Return Policy Procedure.
6.1
Return Material Authorization (RMA) is required
prior to returning equipment to ADTRAN.
6.2
For service, RMA requests, or further information,
contact one of the following numbers.
ADTRAN Customer Service:
RMA
(205) 971-8722
Technical Support
(800) 726-8663
Applications Engineering (800) 615-1176
Sales
(800) 827-0807
Repair and Return Address:
ADTRAN, Inc.
Customer Service Department
901 Explorer Boulevard
Huntsville, Alabama 35806-2807
DEPLOYMENT GUIDELINES
5.1
See Figure 5 for information regarding
deployment guidelines for ISDN 2B1Q loop transmission.
901 Explorer Boulevard • Huntsville, Alabama • 35806-2807 • (205) 971-8000 • FAX (205) 971-8699
Page 5
Section 61153017L3-5, Issue 1
U-RPM
U-LT
LOOP
Total cable make-up
26-gauge
NT1
U-REPEATER III
LOOP
Test Before
Deployment
19
16 kFt
26-gauge
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Test Before
Deployment
DEPLOY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Total cable length
in kFt including
all wire gauges and
bridged taps.
PLOT CABLE MAKE-UP INCLUDING BRIDGED TAPS
18.5 kFt
Mixed Gauge
How to use this guideline:
1. Calculate the total length of 26-gauge wire,
then plot on vertical axis.
2. Calculate the total length of wire in the cable
make-up including 26-gauge and all bridged
taps. Plot this total length on the horizontal
axis.
If the plotted point falls within the solid line boundaries,
the U-Repeater III can generally be deployed without
testing.
If the plotted point is outside the solid line boundary,
long term performance of the U-Repeater III can not be
guaranteed. If deployment is desired, the circuit must
be measured for all line qualification requirements and
must be tested for performance. If these requirements
are not met or performance does not pass, the circuit
must be reengineered.
Line Qualification Requirements
Maximum single bridged tap:
1.5 kFt (0.45 km)
Maximum total bridged tap:
4.5 kFt (1.37 km)
Maximum bridged taps:
3
Maximium resistance:
1300 Ω
(each side)
Maximum loss at 40 KHz:
42 dB
Maximum Noise:
-57 dBm
(135 Ω termination, 50 kB filter)
Maximum impulse noise threshold:
-40 dBm
(135 Ω input, 50 kB filter, seven
or less counts in 15 minutes)
Figure 5. ISDN U-Repeater III (Third Generation) Mixed Gauge Deployment Chart
Page 6
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertising