Avaya Definity SI, Maintenance Manual, Page: 2345 / 2968

STRAT-3 (Stratum 3 Clock)
Issue 4 May 2002 10-1559 555-233-123
Stratum 3 Clock LED Strategy
Red and green LEDs are provided on the components of the Stratum 3 clock for
status and alarm indications.
!
WARNING:
The normal LED scheme is not followed for this device. Green LEDs do not
indicate maintenance activity. There are no yellow LEDs, and there are more
than three LEDs per circuit pack.
The Stratum 3 clock has the following components:
■
2 Clock Input cards (CI)
Provides the logic to select the better DS1 reference or Clock Input card.
The red FAIL LED on this card indicates a failure with the card or the DS1
reference connected to it.
■
2 Stratum 3 Cards (ST3)
Provides 24-hour holdover. The red FAIL LED on this card indicates a
failure with the card. Replace the card.
■
2 Timing Output Cards (TOC)
Provides cable length compensation, multiple output ports, selection of the
ST3, and CI outputs. This type of card has two red failure LEDs: one
indicates a failure of the card; the other indicates a failure in one or more
output ports. In either case, replace the card.
■
1 PBX Alarm Interface (PAI)
Filters power supplied to the clock, provides fuse protection, and provides
alarm indications based on inputs supplied by other cards. The six LEDs on
this card provide indications for the six alarm or status conditions as
follows:
1. Loss of DS1 reference A.
2. Loss of DS1 reference B.
3. Loss of one clock unit.
4. Loss of both clock units.
5. Loss of one power supply.
6. Loss of both power supplies.
NOTE:
Removal of a card in the Stratum 3 clock may cause alarm(s) to be resolved
and the query test to pass. However, the removed cards should still be
replaced to restore the Stratum 3 clock to full service.