CopperOptics PairGain PG-Flex FRE-765 List 5 User manual

PG-FLEX REMOTE TERMINAL ENCLOSURE
Model List Number Part Number
FRE-765 5 150-1365-05
FRE-765 5A 150-1365-51
PAIRGAIN TECHNOLOGIES, INC.
ENGINEERING SERVICES TECHNICAL PRACTICE
SECTION 363-765-105-01
Revision History of this practice.
Revision 01—June 2, 1997
A) Identifies List 5
x RT Enclosures

Section 363-765-105 June 2, 1997 Revision 01
Page ii PairGain Engineering - Plant Series PG-Flex FRE-765
TABLE OF CONTENTS
A. PRODUCT OVERVIEW................................................................................................................1
1. Description and Features....................................................................................................1
2. Specifications....................................................................................................................3
B. FUNCTIONAL DESCRIPTION.....................................................................................................3
3. Operational Capabilities .....................................................................................................3
4. Backplane Connections......................................................................................................5
C. INSTALLATION AND TEST........................................................................................................10
5. Unpacking........................................................................................................................10
6. Installation Requirements .................................................................................................10
7. Mounting..........................................................................................................................11
8. Wiring..............................................................................................................................12
9. Turn-Up and Testing.........................................................................................................15
10. Troubleshooting..............................................................................................................15
D. TECHNICAL SUPPORT................................................................................................................16
11. Technical Support...........................................................................................................16
E. WARRANTY AND CERTIFICATION..........................................................................................16
12. Warranty.........................................................................................................................16
13. Certification.....................................................................................................................17
F. ABBREVIATIONS AND GLOSSARY..........................................................................................17
14. Abbreviations and Glossary ............................................................................................17
USING THIS TECHNICAL PRACTICE
Three types of messages, identified by icons, appear in the text:
A note informs you of special circumstances.
A caution indicatess the possibility of equipment damage.
A warning indicates the possibility of personal injury.
Copyright 1997 PairGain Technologies, Inc.
PairGain is a registered trademark, and PG-Flex is a trademark of PairGain Technologies, Inc.

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 1
A. PRODUCT OVERVIEW
1. Description and Features
1.1 The PairGainPG-FlexFRE-765 List 5xRemoteTerminal (RT) Enclosures (Figures 1 and 2)
provide convenient mounting of one Line Unit and up to four Channel Units, supporting up to 32
channels. The enclosures also provide termination points for subscriber circuits, auxiliary power
pairs, and metallic bypass pair. AMP Quiet Front™ terminations, with internal gas tube protectors,
are provided on the backplane for HDSL and Bypass connections. Optionally, you can add AMP
Quiet Front terminations for auxiliary power pairs when PG-Flex is used with a PG-Flex doubler.
The enclosure can be pole or wall-mounted and is environmentally sealed for outside plant
installations.
Use the List 5 x RT Enclosures only with the FCS-718 List 2 (or higher) or the
FCS-719 List 2 (or higher) COT Shelves.
Figure 1. FRE-765 List 5 RT Enclosure (Inside View)

Section 363-765-105 June 2, 1997 Revision 01
Page 2 PairGain Engineering - Plant Series PG-Flex FRE-765
Figure 2. FRE-765 List 5A RT Enclosure (Inside View)
1.2 Features of the FRE-765 RT Enclosure List 5x include:
•pole or wall mounting
•line power from Central Office Terminal (COT)
•AMP Quiet Front terminations for HDSL inputs, metallic bypass pair, and subscriber
connections (List 5A only)
•AMP Quiet Front terminations can be added for auxiliary power pairs when PG-Flex is used
with a doubler
•5-pin protector strips and AMP Quiet Front terminations for subscriber connections
(List 5A only)
•¾-, 1-, 1½-, 2-inch cable entrance conduct knockouts with rubber grommet
•hinged cover over electronics inside the RT Enclosure
See Table 1 to identify which features are available with each RT Enclosure List 5xmodel.

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 3
Table 1. Features of FRE-765 5x RT Enclosures
List 5
(Figure 1) List 5A (Figure 2)
System 16 Channel ll
32 Channel ll
Subscriber Terminations 25-pr Amphenol (male) l
AMP Insulation Displacement l
Subscriber Protection 5 pin sockets (short housing) l
HDSL Terminations AMP Insulation Displacement ll
2. Specifications
Environmental
Operating Temperature ...............................-40° F to +150° F (-40° C to +65° C)
Operating Humidity ....................................5% to 95% (non-condensing)
Operating Elevation ....................................-200 feet to 13,000 feet (-60 m to 4,000 m)
Physical
Dimensions
Height:.................................................19.25 in. (48.9 cm)
Width:..................................................16.50 in. (41.9 cm)
Depth:..................................................06.44 in. (16.4 cm)
Weight:
List 5:...............................................24.4 lb (11.1 kg)
List 5A: ............................................35.7 lb (16.2 kg)
B. FUNCTIONAL DESCRIPTION
3. Operational Capabilities
3.1 The FRE-765 List 5xRT Enclosure requires the following plug-in units:
•one RT Line Unit which is line powered via the HDSL pairs that connect the RT to the PG-Flex
COT installed in a COT Shelf.
•one Channel Unit, minimum, with a maximum installation of four Channel Units, supporting up
to 32 channels.

Section 363-765-105 June 2, 1997 Revision 01
Page 4 PairGain Engineering - Plant Series PG-Flex FRE-765
3.2 Table 2 shows how circuit assignments are configured in the FRE-765 with the following
deployment rules:
•For channel units providing four (4) circuits, Ckt 1 through Ckt 4 are used for Tip and Ring
terminations.
•For channel units providing eight (8) circuits, Ckt 1 through Ckt 8 are used for Tip and Ring
terminations.
•For a 32-channel system, you can provision a maximum of 32 circuits.
Each PG-Flex channel unit provides four (4) or eight (8) circuits. Table 3 shows how the channels
are assigned, dependent on the type of service provided, such as:
•Plain Old Telephone Service (POTS)
•Integrated Services Digital Network (ISDN)
•Digital Data System (DDS).
Table 2. FRE-765 Circuit Assignments
Line Unit Channel Unit 1 Channel Unit 2 Channel Unit 3 Channel Unit 4
Refer Ckt 1 Ckt 1 Ckt 1 Ckt 1
to Ckt 2 Ckt 2 Ckt 2 Ckt 2
Tables 8, 9, and 10 Ckt 3 Ckt 3 Ckt 3 Ckt 3
for Ckt 4 Ckt 4 Ckt 4 Ckt 4
Line Ckt 5 Ckt 5 Ckt 5 Ckt 5
Unit Ckt 6 Ckt 6 Ckt 6 Ckt 6
Terminations Ckt 7 Ckt 7 Ckt 7 Ckt 7
Ckt 8 Ckt 8 Ckt 8 Ckt 8
Table 3. Channel Unit Circuit Utilization
Channel Unit Service Configurations
Channel Unit 4-Channel POTS 8-Channel POTS 4-Channel ISDN 4-Channel DDS
T/R 1 Ckt 1 Ckt 1 Ckt 1 Ckt 1 Tx
T/R 2 Ckt 2 Ckt 2 Ckt 2 Ckt 1 Rcv
T/R 3 Ckt 3 Ckt 3 Ckt 3 Ckt 2 Tx
T/R 4 Ckt 4 Ckt 4 Ckt 4 Ckt 2 Rcv
T/R 5 — Ckt 5 — Ckt 3 Tx
T/R 6 — Ckt 6 — Ckt 3 Rcv
T/R 7 — Ckt 7 — Ckt 4 Tx
T/R 8 — Ckt 8 — Ckt 4 Rcv

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 5
4. Backplane Connections
4.1 Table 4 lists the FRE-765 List 5xbackplane connectors and where each connector is described in
this practice.
Table 4. FRE-765 List 5x Backplane Connectors
List Connector or Fuse Go to
Table(s) On Page(s)
5 Subscriber Connectors (16/32) 5 and 6 5 and 6
5A Subscriber Connectors (16/32) 7 7 and 8
All Test and Configuration Line-Unit Terminations 8 8
All HDSL, Metallic Bypass, and Auxiliary Power Line-Unit Terminations 9 9
All Power and Ground Line Unit Terminations 10 9
All Fuse 11 9
Table 5. List 5 Subscriber Cable J3 on Connector P3 (16/32 channel)
Cable J3 Connector P3
Channel Unit Circuit Tip Ring Tip Ring
1 WH/BL BL/WH 26 1
2 WH/OR OR/WH 27 2
3 WH/GN GN/WH 28 3
1 4 WH/BN BN/WH 29 4
5WH/SL SL/WH 30 5
6RD/BL BL/RD 31 6
7RD/OR OR/RD 32 7
8RD/GN GN/RD 33 8
1 RD/BN BN/RD 34 9
2 RD/SL SL/RD 35 10
3 BK/BL BL/BK 36 11
2 4 BK/OR OR/BK 37 12
5 BK/GN GN/BK 38 13
6BK/BN BN/BK 39 14
7BK/SL SL/BK 40 15
8YL/BL BL/YL 41 16
Shaded terminations are only used with the 8 channel POTS or 4 channel DDS units.

Section 363-765-105 June 2, 1997 Revision 01
Page 6 PairGain Engineering - Plant Series PG-Flex FRE-765
Table 6. List 5 Subscriber Cable J2 on Connector P2 (16/32 channels)
Cable J2 Connector P2
Channel Unit Circuit Tip Ring Tip Ring
1 WH/BL BL/WH 26 1
2 WH/OR OR/WH 27 2
3 WH/GN GN/WH 28 3
3 4 WH/BN BN/WH 29 4
5WH/SL SL/WH 30 5
6RD/BL BL/RD 31 6
7RD/OR OR/RD 32 7
8RD/GN GN/RD 33 8
1 RD/BN BN/RD 34 9
2 RD/SL SL/RD 35 10
3 BK/BL BL/BK 36 11
4 4 BK/OR OR/BK 37 12
5 BK/GN GN/BK 38 13
6BK/BN BN/BK 39 14
7BK/SL SL/BK 40 15
8YL/BL BL/YL 41 16
Shaded terminations are only used with the 8 channel POTS or 4 channel DDS units.

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 7
Table 7. List 5A Subscriber Terminations
Channel Subscriber Protector
Unit Circuit Connector Pair Strip Socket
1 TB1 1 PB1 1
2 TB1 2 PB1 2
3 TB1 3 PB1 3
1 4 TB1 4 PB1 4
5 TB1 5 PB1 5
6TB1 6 PB1 6
7TB1 7 PB1 7
8TB1 8 PB1 8
1 TB1 9 PB1 9
2 TB1 10 PB1 10
3 TB1 11 PB2 1
4 TB1 12 PB2 2
2 5 TB2 1 PB2 3
6TB2 2 PB2 4
7TB2 3 PB2 5
8TB2 4 PB2 6
1 TB2 5 PB2 7
2 TB2 6 PB2 8
3 TB2 7 PB2 9
3 4 TB2 8 PB2 10
5TB2 9 PB3 1
6TB2 10 PB3 2
7TB2 11 PB3 3
8TB2 12 PB3 4
(continued on next page)

Section 363-765-105 June 2, 1997 Revision 01
Page 8 PairGain Engineering - Plant Series PG-Flex FRE-765
Table 7. List 5A Subscriber Terminations (continued)
Channel Subscriber Protector
Unit Circuit Connector Pair Strip Socket
1 TB3 1 PB3 5
2 TB3 2 PB3 6
3 TB3 3 PB3 7
4 4 TB3 4 PB3 8
5 TB3 5 PB3 9
6TB3 6 PB3 10
7TB3 7 PB4 1
8TB3 8 PB4 2
For the FRE-765, List 5A RT Enclosure the cables on the rear of the
p
rotector/termination
module are installed in connectors P3 and P2 on the FRE-765 backplane.
Shaded terminations only used with the 8 Channel POTS or 4 Channel DDS Units.
Table 8. Test and Configuration Line Unit Terminations
Connector Type Function
ID_0
GND .045 in. Wire-wrap (No Connection - Future)
ID_1
GND .045 in. Wire-wrap (No Connection - Future)
ID_2
GND .045 in. Wire-wrap (No Connection - Future)
TEST_IN_TIP
TEST_IN_RING .045 in. Wire-wrap (No Connection - Future)
TEST_OUT_TIP
TEST_OUT_RING .045 in. Wire-wrap (No Connection - Future)
SSC1_A
SSC1_B .045 in. Wire-wrap (No Connection - Future)
SSC2_A
SSC2_B .045 in. Wire-wrap (No Connection - Future)

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 9
Table 9. HDSL, Metallic Bypass, and Auxiliary Power Line Unit Termination
Back
p
lane
Connector 6 Pair Cable Stub (Lists
4D, 4E)
Type Function
HDSL_1_T
HDSL_1_R WH/BL BL/WH AMP Quiet Front Ti
p
and Rin
g
terminations for HDSL Pair #1 from the COT. -130 Vdc
is simplexed on this line for powering the RT.
HDSL_2_T
HDSL_2_R WH/OR OR/WH AMP Quiet Front Ti
p
and Rin
g
terminations for HDSL Pair #2 from the COT. +130
Vdc is simplexed on this line for powering the RT.
BYPASS_T
BYPASS_R WH/GN GN/WH AMP Quiet Front Ti
p
and Rin
g
terminations for the metallic b
yp
ass
p
air to the COT.
(Note: Do not connect metallic b
yp
ass
p
airs between PG-Flex s
y
stems
or between other DLC systems.)
PWR_1_T
PWR_1_R WH/BN BN/WH AMP Quiet Front Termination for auxiliar
y
p
ower
p
airs when usin
g
a PG-Flex doubler
unit. Note that these connectors must be ordered se
p
aratel
y
(PN 150-
1399-25).
PWR_2_T
PWR_2_R WH/SL SL/WH AMP Quiet Front Termination for auxiliar
y
p
ower
p
airs when usin
g
a PG-Flex doubler
unit. Note that these connectors must be ordered se
p
aratel
y
(PN 150-
1399-25).
(Spare) RB/BL (No connection. For future use.)
(Spare) BL/WH (No connection. For future use.)
Table 10. Power and Ground Line Unit Terminations
Connector Type Function
-48V Screw (No Connection - Future)
GND Screw (No Connection - Future)
CHASSIS GND* Screw Chassis Ground
*Where The FRE-765 is shipped with the “CHASSIS GND” wire-wrap post
connected to the adjacent “GND” wire-wrap post on the RT Backplane.
Table 11. Fuse
Fuse Type Function
F1 GMT 2A (Not required - Future)

Section 363-765-105 June 2, 1997 Revision 01
Page 10 PairGain Engineering - Plant Series PG-Flex FRE-765
C. INSTALLATION AND TEST
5. Unpacking
5.1 Upon receipt of the equipment:
1Unpack each container and visually inspect it 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.
2Check the contents against the packing list to ensure complete and accurate shipment. If the
shipment is short or irregular, contact PairGain as described in Section 12.3. If you must store
the equipment for a prolonged period, store the equipment in its original container.
6. Installation Requirements
6.1 Prior to installing the FRE-765, be aware of these installation requirements or conditions shown in
Table 12.
Table 12. Installation Requirements
Requirement Description
Environmental The FRE-765 can o
p
erate in an outside
p
lant environment. It can o
p
erate in a tem
p
erature
ran
g
e of -40°F to +150°F (-40°C to +65°C) and a humidit
y
ran
g
e of 5% to 95% (non-
condensing).
Mounting The FRE-765 has external mountin
g
flan
g
es with a clearance hole for a 3/8-inch bolt for
p
ole or wall mountin
g
. The customer must
p
rovide the a
pp
ro
p
riate mountin
g
hardware.
When mountin
g
to a
p
ole usin
g
the Pole Mountin
g
Kit (PN 150-1397-00), ensure that the
pole mounting bracket and FRE-765 are fully installed before installing cabling.
Power The FRE-765
g
ets
p
ower from the HDSL lines connected to the COT shelf in the
Central Office (CO). When a doubler is installed between the PG-Flex COT Shelf and RT
enclosure, two additional power pairs are required from the COT shelf and RT enclosure.
HDSL Lines Two HDSL pairs are terminated in the FRE-765.
Subscriber Lines
List 5 Provides three 25-pair Amphenol connectors (male) for subscriber line terminations.
List 5A Provides AMP Quiet Front insulation displacement connections for subscriber terminations.
Metallic Bypass Pair The metallic b
yp
ass
p
air for subscriber line testin
g
is terminated in the FRE-765. Do not
connect the bypass pairs between PG-Flex systems or to other DLC systems.
Doubler When usin
g
a doubler, add two AMP Quiet Front terminals to the FRE-765 to terminate
the auxiliar
y
p
ower
p
airs from the COT. Order the Quiet Front kit (PN 150-1399-25) which
contains two Quiet Front terminations, four
j
um
p
ers, and a tool for insertin
g
the
j
um
p
ers
into the insulation displacement barrels.
Cable Entry Knockouts are located on the bottom of the FRE-765 and acce
p
t ¾-, 1-, 1½-, and 2-inch
fittin
g
s. Install
g
rommet (
p
rovided with FRE-765), conduit, or cable strain relief fittin
g
s
prior to wiring the FRE-765.
Protectors Install 5-
p
in
p
rotectors (short housin
g
) for each workin
g
subscriber circuit in the FRE-765
List 5A. These ma
y
be carbon,
g
as tube, or solid state
p
rotectors, de
p
endin
g
on local
practice.

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 11
7. Mounting
7.1 The FRE-765 mounts on a pole or a wall. Follow local practices to ensure a secure mounting.
Mount the FRE-765 for easy access to the cable entry points on the bottom of the enclosure. Provide
ample room to open the door completely.
7.2 For pole mounting the FRE-765, use the Pole Mounting Kit PN 150-1397-00. Follow the
instructions that are included to install the pole mounting bracket. Then, mount the FRE-765 to the
bracket. Do not install any cabling until the FRE-765 is securely mounted.
7.3 When required, install the grommet into the base of the FRE-765 (Figure 3) prior to performing any
wiring.
1Select only one concentric knockout hole on the FRE-765.
2Remove the largest knockout so that the entire hole is open.
3Install the grommet from the outside of the FRE-765. (Hint - Hold it at an angle to the hole and
roll it into position.)
4Ensure the lip of the grommet rests on the bottom of the FRE-765 around the knockout hole.
5Use an appropriate tool to open the required hole(s) in the bottom of the grommet.
Figure 3. Installing the Grommet

Section 363-765-105 June 2, 1997 Revision 01
Page 12 PairGain Engineering - Plant Series PG-Flex FRE-765
Table 13 shows the wire gauges that can be installed through the holes in the grommet.
Table 13. Grommet Hole Diameters
For this grommet hole size Use this cable
.410 to .765 in. diameter (two) *• 24 or 26 AWG, 25- or 50-
p
air Primar
y
Interexchan
g
e Carrier (PIC)
(filled or non-filled)
• 22 AWG, 25-pair PIC (filled or non-filled)
• 22, 24, or 26 AWG , 6- or 11-pair PIC (filled or non-filled)
.240 to .275 in. diameter (one) ground wire

.155 to .240 in. diameter (one) ground wire 
*Recommend usin
g
one hole for both the HDSL and the b
yp
ass
p
airs (i.e., 6-
p
air cable) and the second hole for POTS
(subscriber) lines.
 Dependent upon gauge of wire used.
8. Wiring
8.1 Sections 8.2 through 8.7 describe how to connect the FRE-765 cables. Section 8.8 verifies
the installation.
8.2 Chassis Ground Wiring. Install the chassis ground (Figure 4):
Use 6 AWG or larger wire to ensure a good ground connection to the FRE-765.
1Route the chassis ground wire through the small hole in the strain relief on the bottom of the
enclosure (Figure 4).
2Connect one end of the chassis ground wire to grounding lug CHASSIS GND.
3Connect the other end of the chassis ground wire to a suitable ground termination point (ground
rod or cold water pipe).
4Tighten the strain relief around the wire or use a cable tie to secure to the bracket near the cable
entrance.
Figure 4. Installing the Ground

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 13
8.3 HDSL Lines. Install the HDSL lines (Figure 5):
1Route the HDSL pairs through the strain relief on the bottom of the enclosure.
2Terminate HDSL Pair #1 on the Quiet-Front terminals HDSL_1_T (Tip) and
HDSL_1_R (Ring).
3Terminate HDSL Pair #2 on the Quiet-Front terminals HDSL_2_T (Tip) and HDSL_2_R (Ring).
4Use a cable tie to secure to the bracket near the cable entrance.
Figure 5. Installing HDSL Lines and Bypass Pair
8.4 Bypass Pair. Install the Bypass Pair (Figure 5):
Do not connect metallic bypass pairs between PG-Flex systems or to other DLC
systems.
1Route the bypass pair through the strain relief on the bottom of the enclosure.
2Terminate the bypass pair on the Quiet Front terminals BYPASS_T and BYPASS_R.
3Use a cable tie to secure to the bracket near the cable entrance.
8.5 Subscriber Lines. To install the subscriber lines, do one of the following:
Use the cable adapter (PN 120-1111-02) installed on the RT Enclosure to ensure
the subscriber terminations match the information shown in Tables 5 through 9.
•For List 5 FRE-765 enclosure:
1Route the subscriber line cables through the strain relief on the bottom of
the enclosure and connect to P2 and P3 connectors.
2Terminate the subscriber line cables per Tables 4 and 5.
3Secure with a cable tie to the bracket near the cable entrance.
•For List 5A FRE-765 enclosure:
1Route the subscriber line cables through the desired knockout on the bottom of
the enclosure.
2Terminate the subscriber line cables per Table 6.
3Use a cable tie to secure to the bracket near the cable entrance.

Section 363-765-105 June 2, 1997 Revision 01
Page 14 PairGain Engineering - Plant Series PG-Flex FRE-765
8.6 Protector Plugs. For the FRE-765 List 5A, install five-pin protector plugs into the protector strips
for each subscriber line installed (Figure 6). See Table 7 for protector socket locations.
Figure 6. Installing Five-Pin Protector Plugs
8.7 Auxiliary Power Pairs. When PG-Flex is used with a doubler, install the two AMP Quiet Front
terminations (PN 150-1399-25) and wire for the doubler. The installation kit provides white and blue
jumper wires. Install the two AMP Quiet Front terminations into the FRE-765 (Figure 7) enclosure:
1Connect a white jumper wire to PWR_1_T (J10) and a blue jumper wire to PWR_1_R (J11)
barrel connectors.
2Connect a white jumper wire to PWR_2_T (J12) and a blue jumper wire to PWR_2_R (J13)
barrel connectors.
3Back out the phillips-head screw for each connector and slide the bracket on the AMP Quiet
Front terminator under it.
4Tighten the phillips-head screw.
5Insert and tighten the white and blue jumpers into the AMP Quiet Front terminations.

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Figure 7. Installing Doubler Termination Points
8.8 Cabling Verification. Verify the following connections.
Perform the following verifications before inserting any cards in the COT shelf.
1Visually ensure the ground wire is tightly secured to the grounding lug inside the FRE-765 and
at the ground termination point.
2Visually verify the HDSL lines are terminated properly and with the correct orientation. If the
HDSL lines are not connected properly, the COT will not communicate with the FRE-765.
3Verify that the HDSL lines are "dry."
aVerify 0 Vdc between the Tip and Ring, Tip and ground, and Ring and ground of each of
the HDSL pairs terminated at the FRE-765.
bVerify a value greater than 100 kohms resistance between Tip and ground and Ring and
ground for each of the HDSL pairs terminated at the FRE-765.
9. Turn-Up and Testing
9.1 Refer to the COT Line Unit Technical Practice or RT Line Unit Technical Practice for complete
COT and RT turn-up and testing procedures.
10. Troubleshooting
10.1 Refer to the COT Line Unit Technical Practice or RT Line Unit Technical Practice for complete
COT and RT troubleshooting procedures

Section 363-765-105 June 2, 1997 Revision 01
Page 16 PairGain Engineering - Plant Series PG-Flex FRE-765
D. TECHNICAL SUPPORT
11. Technical Support
11.1 PairGain Technical Assistance is available 24-hours-a-day, 7-days-a-week by contacting PairGain
Customer Service Engineering group at:
Telephone: [phone] or [phone]
Fax: [phone]
11.2 During normal business hours (8:00 AM to 5:00 PM, Pacific Time, Monday - Friday, excluding
holidays), technical assistance calls are normally answered directly by a Customer Service Engineer.
At other times, a request for technical assistance is handled by an on-duty Customer Service
Engineer through a callback process. This process normally results in a callback within 30 minutes
of initiating the request.
11.3 In addition, PairGain maintains a computer bulletin board system for obtaining current information
on PairGain products, product troubleshooting tips and aids, accessing helpful utilities, and for
posting requests or questions. This system is available 24-hours-a-day by calling [phone].
Transmission speeds up to 28.8 kbps are supported with a character format of 8-N-1.
E. WARRANTY AND CERTIFICATION
12. Warranty
12.1 PairGain Technologies warrants this product to be free of defects and to be fully functional for a
period of 60 months from the date of original shipment, given proper customer installation and
regular maintenance. PairGain will repair or replace any unit without cost during this period if the
unit is found to be defective for any reason other than abuse or improper use or installation.
12.2 Do not try to repair the unit. If it fails, replace it with another unit and return the faulty unit to
PairGain for repair. Any modifications of the unit by anyone other than an authorized PairGain
representative voids the warranty.
12.3 If a unit needs repair:
1Call PairGain for a Return Material Authorization (RMA) number at [phone].
2Return the defective unit, freight prepaid, along with a brief description of the problem, to:
PairGain Technologies, Inc.
14402 Franklin Avenue
Tustin, CA 92780-7013
ATTN: Repair and Return Dept.
12.4 PairGain continues to repair faulty modules beyond the warranty program at a nominal charge.
Contact your PairGain sales representative for details and pricing.

Revision 01 June 2, 1997 Section 363-765-105
PG-Flex FRE-765 PairGain Engineering - Plant Series Page 17
13. Certification
13.1 FCC Compliance. The FRE-765 List 5xRT Enclosure has been tested and found to comply with
the limits for Class A digital devices pursuant to Part 15 of the FCC rules. These limits are designed
to provide reasonable protection against harmful interference when the equipment is operated in a
commercial environment. This equipment generates, uses and can radiate radio frequency energy
and, if not installed and used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a residential area is likely to
cause harmful interference in which case the user will be required to correct the interference at his
own expense.
13.2 Refer to the installation section of the instruction manual of the unit you are installing for
information on:
• cabling
• proper connections
• grounding
13.3 Follow the provisions of the current edition of the National Electrical Code for wiring external to the
product(s).
F. ABBREVIATIONS AND GLOSSARY
14. Abbreviations and Glossary
CO Central Office
COT Central Office Terminal
DDS Digital Data System
DLC Digital Loop Carrier
HDSL High bit-rate Digital Subscriber Line
ISDN Integrated Services Digital Network
PIC Primary Interexchange Carrier
POTS Plain Old Telephone Service
RT Remote Terminal