CopperOptics PairGain PG-Flex FLC-703 User manual

PAIRGAIN TECHNOLOGIES Section 363-703-103
Technical Practice Revision 01
Engineering - PLANT Series December 18, 1996
Page 1
PG-FLEX™8 CHANNEL COT POTS UNIT
MODEL FLC-703
List # PairGain Part # CLEI Code
1 150-1303-01 N/A
2 150-1303-02 VACHCDECAA
3 150-1303-03 VACHCDGCAA
CONTENTS PAGE
A. PRODUCT OVERVIEW
1. DESCRIPTION
AND FEATURES 2
2. APPLICATIONS 2
3. SPECIFICATIONS 3
4. CERTIFICATION 4
5. WARRANTY 4
B. FUNCTIONAL DESCRIPTION
6. OPERATIONAL
CAPABILITIES 4
7. FRONT PANEL 5
C. INSTALLATION AND TEST
8. UNPACKING 5
9. TURN-UP AND TESTING 5
10. TROUBLESHOOTING 5
CAUTION
This product incorporates static sensitive components.
Proper electrostatic discharge procedures must be
followed.
Figure 1. FLC-703 COT Channel Unit Front Panel. The
PairGain FLC-703 provides eight POTS interfaces between the
Central Office and PG-Flex.

Section 363-703-103
Revision 01
Page 2
A. PRODUCT OVERVIEW
1. DESCRIPTION AND FEATURES
1.01 The PG-Flex FLC-703 Channel Unit provides 8
POTS interfaces between the Central Office and
PG-Flex, and uses µ-Law PCM encoding. The Model FLC-
703 Channel Unit includes green status LEDs for each line
indicating idle, ringing, and off-hook conditions, as well as a
red LED indicating a fault condition on the Channel Unit.
The unit provides metallic test access to the subscriber line
connection through an optional metallic bypass pair.
1.02 Revision History of this practice.
Revision 02—December 18, 1996
a) Added List 3.
1.03 Features of the PG-Flex FLC-703 COT Channel
Unit:
• Eight POTS subscriber interfaces
• 64 kbps µ-Law PCM encoding
• Front panel ACTIVE LEDs indicate idle, ringing,
test access, and off-hook for each channel
• Front panel FAULT LED indicator simplifies
troubleshooting
• Pair Gain Test Controller (PGTC) Compatibility -
List 3 only
2. APPLICATIONS
2.01 Subscriber Drop Testing. For subscriber drop
testing from the central office, PG-Flex is able to
select and connect any subscriber drop to a metallic test pair
at the RT. PG-Flex extends this connection back to the COT
where it can be switched onto the test access bus, or to the
corresponding subscriber line on the COT channel card.
2.02 Test access may be achieved by placing +116 V on
the subscriber’s COT tip lead for 1.5 seconds, then
removing the +116 V. Depending on the configuration of the
PG-Flex system, the selected subscriber drop (assuming a
working metallic bypass pair) will be connected to either the
corresponding COT subscriber line or to the test access bus.
2.03 The test connection will be dropped when -116V is
applied to the subscriber’s COT tip for 1.5 seconds,
then removing the -116 V.
2.04 Test access may also be activated through the
RS-232 Maintenance Port located on the front of the
COT Line Unit, using an ASCII terminal.

Section 363-703-103
Revision 01
Page 3
Figure 2. Typical PG-Flex Configuration.
3. SPECIFICATIONS
Analog Impedance
900 ohms
DC On-Hook Resistance
Greater than 4 megohms between Tip and Ring
at the output of the COT
DC Off-Hook Resistance
960 ohms
Channel Signature
Tip Ring: (open)
Tip Ground: 162 kohm, 1%
Ring-Ground: 226 kohm, 1%
COT 20-Hz Input Impedance
0.9 REN
COT Ring Detection
The COT channel unit recognizes an ac signal
between tip and ring leads with an amplitude
from 65 Vrms to 104 Vrms and frequency
between 16 Hz and 50 Hz as a ringing signal.
This signal may be superimposed on a dc
component of -36.0 Vdc to -56.5 Vdc applied to
the ring lead with respect to the tip lead. The
tip lead may or may not be referenced to
ground. The source impedance of the ringing
signal must be less than 500 ohms.
Operating Temperature & Humidity
-40° F to +150° F (-40°C to +65° C)
5% to 95% (non condensing)
Operating Elevation
-200 ft. to 13,000 ft.
(-60 m to 4,000 m)
Dimensions
Height: 6.75” (17.2 cm)
Width: 1.00” (2.5 cm)
Depth: 10.50” (26.7 cm)
Weight
0.8 lb. (0.4 kg)

Section 363-703-103
Revision 01
Page 4
4. CERTIFICATION
4.01 FCC Compliance. The FLC-703 Channel Unit
complies 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.
4.02 Refer to the installation section of the appropriate
instruction manual for the unit you are installing to
get information on:
• Cabling
• Proper connections
• Grounding
• Line power
4.03 All wiring external to the product(s) should follow
the provisions of the current edition of the National
Electrical Code.
5. WARRANTY
5.01 PairGain Technologies warrants this product to be
free of defects and to be fully functional for a period
of 5 years 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.
5.02 This module should not be field repaired. 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 will
void the warranty.
5.03 If a unit needs repair, call PairGain for a Return
Material Authorization (RMA) number and return
the defective unit, freight prepaid, along with a brief
description of the problem, to:
PairGain Technologies, Inc.
2120 Ritchey St.
Santa Ana, CA 92705-5101
ATTN: Customer Repair Facility
[phone]
5.04 PairGain will continue to repair faulty modules
beyond the warranty program at a nominal charge.
Contact your PairGain sales representative for details and
pricing.
B. FUNCTIONAL DESCRIPTION
6. OPERATIONAL CAPABILITIES
6.01 The FLC-703 Channel Unit provides 8 POTS
interfaces to the CO switch. The card performs the
interface function between the analog POTS circuit and the
internal digital PCM bus. In addition, each card:
• Converts analog signals to 64 kbps µ-Law PCM
digital format
• Detects ringing voltage
• Detects forward disconnect
• Detects a subscriber test access signal
• Provides loop closure
• Pair Gain Test Controller (PGTC) compatibility
6.02 A block diagram of the FLC-703 Channel Unit is
shown in Figure 3. One 8-Channel COT POTS Unit
supports eight POTS interfaces.
6.03 A status LED is associated with each line to indicate
whether the line is off-hook, idle, ringing, or being
tested. A common fault LED indicates a general fault has
been detected on the card and it should be replaced.
6.04 Test access connections to a specific line circuit are
made through the maintenance terminal or by the
CO switch applying the appropriate voltages on the
subscriber line (see paragraphs 2.01 through 2.04).

Section 363-703-103
Revision 01
Page 5
Figure 3. FLC-703 Block Diagram.
7. FRONT PANEL
7.01 The front panel of the FLC-703 Channel Unit
contains the following indicators (see Figure 1):
• ACTIVE 1-8 LED Indicators
Green—the channel is off-hook.
Flashing Green—(slow flash) the channel is ringing
(the LED will track the ringing) or the line has been
switched to the test pair.
Off—the channel is on-hook or not connected.
• FAULT LED Indicator
Red—a fault has been detected by the unit.
Off—no faults are detected by the unit.
C. INSTALLATION AND TEST
8. UNPACKING
8.01 Upon receipt of the equipment, proceed as follows:
1. Unpack 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.
2. Check the contents versus the packing list to
ensure complete and accurate shipment. If the
shipment is short or irregular, contact PairGain as
described in Section 5. If you must store the
equipment for a prolonged period, store the
equipment in its original container.
9. TURN-UP AND TESTING
9.01 Table 2 provides step-by-step turn-up and test
procedures for the FLC-703 Channel Unit.
10. TROUBLESHOOTING
10.01 Table 3 provides troubleshooting procedures based
on indications displayed by the front panel
indicators of FLC-703 Channel Unit.

Section 363-703-103
Revision 01
Page 6
TABLE 2. FLC-703 CHANNEL UNIT TURN-UP AND TESTING
CAUTION
Observe normal electrostatic discharge precautions when handling
electronic equipment. Do not hold electronic plugs by their connector
edges. Do not touch components or circuitry.
Step Operation Action Observe
1 Install
COT
Channel
Units
a. Insert each FLC-703
Channel Unit into the
COT Shelf.
All LEDs on the Channel
Unit will turn on for
approximately ½ second,
then scan from top to
bottom, then flash all on,
then off.
b. After the system has
powered up,
established HDSL
synchronized
communications, and
no calls are in
progress, observe the
Channel Unit front
panel indicators.
ACTIVE 1 off
ACTIVE 2 off
ACTIVE 3 off
ACTIVE 4 off
ACTIVE 5 off
ACTIVE 6 off
ACTIVE 7 off
ACTIVE 8 off
FAULT off
2 Test
Subscriber
Circuits
a. Test each subscriber
circuit by placing and
receiving calls.
ACTIVE 1 through 8
LEDs track call progress
as described in paragraph
7.01.

Section 363-703-103
Revision 01
Page 7
TABLE 3. FLC-703 RT CHANNEL UNIT TROUBLESHOOTING
Indication Problem Action
FAULT LED
on The processor in the Channel Unit
has stopped.
Remove and re-insert the Channel Unit. If the system does not
restart, replace the Channel Unit.
Troubleshooting based on customer-originated trouble reports
No Dial tone,
Can’t Dial Short circuit, faulty COT Channel Unit,
or faulty RT
Channel Unit.
1. Lift the subscriber pair at the RT. If dial tone is present and
calls can be placed, check for shorts toward the subscriber.
2. If you cannot hear a dial tone and/or cannot make calls at the
RT with the subscriber drop lifted, lift the jumper in the CO
between the CO switch and the COT. If you hear a dial tone
and/or can make calls at the switch, try listening for dial tone
on another subscriber pair on a different RT Channel Card. If
dial tone is present on another pair, then replace the COT
Channel Unit and/or RT Channel Unit. If dial tone is not
present on the second subscribe pair, replace COT on RT Line
Unit. Otherwise, the problem is in the CO switch.
Phone
Doesn’t
Ring
High-resistance
short on subscriber
drop, faulty RT
Channel Unit, or
faulty RT Line
Unit.
1. Check for ringing at the RT. If ringing isn’t present on the line
under test, try ringing another line terminated on the same RT
Channel Unit. If ringing is present on other lines, check for
high resistance shorts on the subscriber drop. If no high
resistance shorts, replace the RT Channel Unit.
2. If ringing isn’t present on a circuit terminated on the same RT
Channel Unit, try ringing a line terminated on another RT
Channel Unit. If the line rings, replace the RT Channel Unit. If
the line doesn’t ring, replace the RT Line Unit.
Phone
Doesn’t
Stop
Ringing
Faulty subscriber
station instrument,
faulty RT Channel
Unit, or loop
length too long.
1. Phone stops ringing when using a butt-in at subscriber location:
a) Subscriber’s station instrument’s internal resistance is too
high. Replace instrument according to local policies.
2. If phone doesn’t stop ringing when using a butt-in at the
subscriber location, re-test at the RT:
a) If phone still doesn’t stop ringing, replace the RT Channel
Unit.
b) Otherwise, loop length between RT and subscriber is too long.
Can’t
Hear,
Can’t Be
Heard
Subscriber
problem, faulty
COT Channel Unit,
or faulty RT
Channel Unit.
1. Lift the subscriber drop at the RT. If audible level is acceptable,
there is a problem toward the subscriber.
2. If audible level is too low at the RT with the subscriber drop
lifted, lift the jumper in the CO between the CO switch and the
COT. If audible level is acceptable, replace the COT Channel
Unit and/or RT Channel Unit. Otherwise, the problem is in the
CO switch.
Copyright © 1996, PairGain Technologies, Inc. PairGain is a registered trademark, CopperOptics and PG-Flex are trademarks of
PairGain Technologies, Inc.