Maintenance Description
Issue 8.0 July 2002
9-43
intervention. For more information about clearing a potential loss of service
due to a double failure, refer to the "Operation and Maintenance (TOP)"
section (Volume II).
Figure 9-10. Single and Double Failures
Electrical Low Speed Protection 9
The FT-2000 OC-48 Lightwave System provides protection for all the low-speed
interface circuit packs. The DS3 Interface circuit packs and STS-1 Electrical
Interface circuit packs are 1xM (M≤16) protected and use bidirectional revertive
switching. Low speed protection switching takes place in response to
automatically detected faults and external commands from a local/remote CIT or
operations system. Refer to the FAULT-Switch-Low Speed input in Volume I,
Section 11, "Craft Interface Terminal Usage."
Node 0
1W 1E
1A 2B 8B
1
OC-48
5A
14
1
6
Node 1
1W 1E
1A 8B
14
1
14
1
66
Node 3
1E 1W
1A 8B
1
OC-48
14
1
Node 2
1E 1W
1A 8B
14
1
14
1
6
OC-48OC-48
4A
16
16 16 16
16 16 16 16
3 3 3
3
3A
2A 4B
Failure A
Node Power Failure
Failure B
Fiber Cut
Failure C
Fiber Cut