PairGain FLC-703, Manual

Page: 10 / 14

Subscriber Drop Testing 363-703-131-01, Revision 01
6 July 30, 1999 FLC-703 List 3A
S
UBSCRIBER
D
ROP
T
ESTING
For PG-Flex subscriber drop testing from the CO, select and connect any subscriber drop to a metallic test pair at
the RT. PG-Flex extends this connection to the COT where it can be switched onto the test access bus or to the
corresponding subscriber line on the COT channel card.
Activate test access through the RS-232 maintenance port located on the front of the COT Line Unit using an
ASCII terminal.
Table 1 on page 2 provides PG-Flex system troubleshooting procedures based on indications displayed by the
FLC-703 Channel Unit front panel LEDs or customer reported problems.
Indication Problem Action
FAULT
LED On The FLC-703
processor has
detected a fault. Remove and re-insert the CU. If the FAULT LED does not extinguish, replace the CU.
Troubleshooting based on customer-originated trouble reports
No dial
tone, can
not dial
•
faulty RT or
COT CU
• facility
short/open
• CO switch
problem
1 Lift the subscriber pair at the network interface. If dial tone is present and you can place a call,
refer the problem to the customer per local practice.
2 If you cannot hear dial tone or place a call at the network interface (with the subscriber pair
lifted), check for dial tone at the RT. If dial tone is present, check the pair between the RT and
the network interface. If no dial tone is present, replace the RT CU.
3 If the problem still exists, re-insert the original RT CU and replace the COT CU. Test for
operation.
4 If the problem still exists, refer the problem to the CO switch.
Phone
does not
ring
•
high-resistance
subscriber line
short
•
faulty RT or CO
CU
• loop length too
long
1 Lift the subscriber pair at the network interface. If ringing is present, refer the problem to the
customer per local practice.
2 If ringing is not present, check for ringing at the RT. If ringing is present, check the pair between
the RT and the network interface. If no ringing is present, replace the RT CU. If ringing is still
not present, check a circuit on another CU. If ringing is still not present, replace the LU.
3 If ringing is still not present at the RT, re-insert the original CU and LU. Test for ringing at the
COT.
4 Test for ringing into the COT from the CO switch. If no ringing is present, refer the trouble to
the CO switch. If ringing is present, replace the COT CU. Test again for ringing at the network
interface. If ringing is still not present, contact PairGain technical assistance (see
“Product
Support” on Inside back cover ).
5 Verify the resistance of the copper loop between the RT Enclosure and the network interface is
less than 530
Ω
.
Phone
does not
stop
ringing • faulty
subscriber
instrument
• faulty RT CU
• loop length too
long
1 Test for ring trip at the network interface. If the ringing is tripped, refer the trouble to the
customer per local practice.
2 If the ringing is not tripped, test for tripping at the RT. If ring trip does occur, check the loop for
excessive length. If ring trip does not occur, replace the RT CU. If ring trip still does not occur,
contact PairGain technical assistance (see
“Product Support” Inside back cover ).
3 Verify the resistance of the copper loop between the RT Enclosure and the network interface is
less than 530
Ω
.
Can not
hear, Can
not be
heard
•
subscriber
problem
• faulty RT or
COT Channel
Unit (CU)
1 Lift the subscriber line at the network interface and check the signal level. If correct, refer
trouble to the customer per local practice.
2 2 If the level is too low, check the level at the RT. If the level is correct at the RT, check the pair
between the RT and the network interface. If the level is too low at the RT, replace the RT CU.
3 3 If the level is still too low, re-insert the original RT CU.
4 4 Check the level at the COT coming from the CO switch. If it is correct, replace the COT CU. If
it is not correct, refer the problem to the CO regarding the switch.
5 5 If the level is still not correct, re-insert the original COT CU. Contact PairGain technical
assistance (see
“Product Support” Inside back cover ).