MODEL7304 User Manual
Page 11 of 11
6.
6.
6.
6. Common
Common
Common
Common Problems
Problems
Problems
Problems
Common
Common
Common
Common Failures
Failures
Failures
Failures and
and
and
and Solutions
Solutions
Solutions
Solutions
No.
Failure
Cause
Solution
1
PWR
power
supply
indicator
lamp
not
lightening
1.Power supply not properly
connected
2.Protector tube damaged
3. -48V DC input tie-line in
reverse connection
4.Internal power supply circuit
with failure
1.Check
power
switch
and
jack
2.Replace protector tube 3.Correct -48V
power supply line connection
4.Returned to the manufacturer for
repair.
2
LOF
out-of-frame
alarm lamp lightening
1.Optic interface not clean
2.Optic fiber not well inserted
3.Wrong clock setting
4.Time slots of the devices at
two ends not conformance
5.Internal circuit damaged
1. Clean the connector of optic interface
2. Insert the SC connector in place
3. Refer to the description on rear panel
4. Returned to the manufacturer for
repair.
3
LOS data loss alarm
lamp lightening
1.
Optic
fiber
in
wrong
interconnection
2.Optic fiber not well inserted
3.Optic fiber broken
4.Internal circuit damaged
1. Correct the connection
2. Insert the SC connector in place
3. Check optic cable
4. Returned to the manufacturer for
repair.
4
TXD
lamp
not
lightening
V.35
interface
not
well
connected or the router etc. not
turned on.
1.
Check
the
connecting
line
and
terminal device
