Lucent Technologies DDM-2000 OC-3, User & Service Manual

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363-206-285
Circuit Pack Descriptions
7-126 Issue 3 June 2001
24G-U OLIU Circuit Pack Description 7
Purpose of Circuit 7
The 24G-U OC-12 OLIU circuit pack performs the optical/electrical conversion
between the optical carrier level 12 (OC-12) and STS-12 signals, multiplexing
between STS-12 and twelve STS-1 signals, and SONET transport overhead
access. The 24G-U OLIU also provides routing of any 3 of the twelve STS-1s
between the OC-12 interface and other main and function unit slots in the shelf as
well as VT1.5/STS-1 add/drop and ring capabilities. When used to perform VT1.5
add/drop or ring capabilities, STS-1 path overhead access is also provided.
The 24G-U OLIU can also be used as an OC-12 upgrade from an OC-3 ring.
24G-U OLIU Faceplate Indicators 7
The 24G-U OLIU circuit pack faceplate indicators are shown in Figure 7-45.
The red FAULT LED lights on detection of circuit pack hardware failure. In the
event of an incoming signal failure, this LED will flash on and off.
The green ACTIVE LED lights when the circuit pack is active (carrying service).
A faceplate-mounted universal optical connector allows the 24G-U OLIU to accept
fiber terminated with
ST , SC, or FC connectors. An additional interconnect cable
assembly is required between faceplates of the two 24G-Us to support pass-
through traffic on the OC-12 ring (see Figure 7-45). The 24G-U OLIU comes with
a 0 dB
ST buildout. For the 24G-U, a 10 dB attenuator is required for loopback
testing. The 24G-U OLIU operates over single-mode fiber. Various combinations
of buildout attenuators and connectors are also available. See Section 10,
"Technical Specifications," for a list of universal buildout attenuators.