Test Telephones and Other Equipment
Task List: Test Stratum 3 Clock
738
SI Installation and Upgrades
June 2004
These procedures test the ability of the Stratum 3 clock to correctly provide timing and alarms to the
system.
CAUTION:
The following procedures are destructive to DS1 data and should not be attempted while
DS1 facilities are active.
Task List: Test Stratum 3 Clock
1
Check for Red LEDs
on page 738
2
Verify Timing to the System
on page 739
Check for Red LEDs
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1
Turn on the Stratum 3 clock and wait 40-50 seconds to allow the system to complete the on-board
diagnostics before checking LEDs.
2
If there are any red LEDs, follow the procedures in
Table 32
.
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Table 32: Stratum 3 Clock LED Indicators
Card
LED Label
Procedure
PAI
REF A
Check that the CI circuit pack on the left is inserted properly. Check wiring for DS1 in
carrier “A” which connects the system to the CSU and the External Synchronization
Clock at the MDF through a Y-cable assembly. If all else fails to clear the LED then
replace the circuit pack.
PAI
REF B
Check that the CI circuit pack on the right is inserted properly. Check wiring for DS1
in carrier B which connects the system to the CSU and the External Synchronization
Clock at the MDF through a Y-cable assembly. If all else fails to clear the LED then
replace the circuit pack.
PAI
ST A
Replace the ST3 card
PAI
ST B
Replace the ST3 card
CI
FAIL
Check wiring for its associated DS1 reference and replace the circuit pack if necessary
ST3
FAIL
Replace the circuit pack
ST3
LOCK
Ignore this LED
ST3
HOLDOVER
Ignore this LED
ST3
FREE RUN
Ignore this LED
TOCA
FAIL
Replace the circuit pack
TOCA
PORT ALM
Replace the circuit pack if necessary
