Table of Contents
Advertisement
Troubleshooting
C
R
USTOMER
EPORTED
Table 2
provides troubleshooting procedures based on customer reported problems.
Problem
Cause
No dial tone,
•
faulty RT or COT Channel
can not dial
Unit
•
facility short/open
CO switch problem
•
Phone does
•
high-resistance subscriber
not ring
line short
•
faulty RT or CO Channel
Unit
•
•loop length too long
Phone does
•
faulty subscriber
not stop
instrument
ringing
faulty RT Channel Unit
•
•
loop length too long
Can not
•
subscriber problem
hear, can
•
faulty RT or COT Channel
not be heard
Unit
8
P
ROBLEMS
Table 2. FRC-753 RT Channel Unit Troubleshooting
Action
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 cannot 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 Channel Unit.
3 If the problem still exists, re-insert the original RT Channel Unit and replace the
COT Channel Unit. Test for operation.
4 If the problem still exists, refer the problem to the CO switch.
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 Channel Unit. If ringing is still not present, check a circuit on
another Channel Unit. If ringing is still not present, replace the RTLU.
3 If ringing is still not present at the RT, re-insert the original Channel Unit and
Line Unit. Test for ringing at the COT shelf.
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 Channel Unit.
Test again for ringing at the network interface. If ringing is still not present,
contact PairGain technical assistance (refer to
back
cover).
5 Verify the resistance of the copper loop between the RT Enclosure and the
network interface is less than 530 Ω.
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
Channel Unit. If ring trip still does not occur, contact PairGain technical
assistance (refer to
3 Verify the resistance of the copper loop between the RTE and the network
interface is less than 530 Ω.
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 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 Channel Unit.
3 If the level is still too low, re-insert the original RT Channel Unit.
4 Check the level at the COT shelf coming from the CO switch. If it is correct,
replace the COT Channel Unit. If it is not correct, refer the problem to the CO
regarding the switch.
5 If the level is still not correct, re-insert the original COT Channel Unit. Contact
PairGain technical assistance (refer to
cover).
July 23, 1999
"Technical Support" on Inside
"Technical Support" on Inside back
"Technical Support" on Inside back
363-753-142-01, Revision 01
cover).
FRC-753 List 4B
Advertisement
Table of Contents
