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

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363-206-285
Circuit Pack Descriptions
7-118 Issue 3 June 2001
22G-U/22G2-U/22G3-U/22G4-U OLIU Circuit Pack
Description
7
Purpose of Circuit 7
The 22G-U/22G2-U/22G3-U
/22G4-U
OLIU circuit pack performs the optical/
electrical conversion between the optical carrier level 3 (OC-3) and STS-3 signals,
multiplexing between STS-3 and three STS-1 signals and SONET transport
overhead access. The 22G-U/22G2-U/22G3-U
/22G4-U
OLIU also provides
routing of the STS-1s between the OC-3 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 22G2-U/22G3-U
/22G4-U
OLIU is the same as the 22G-U but has improved
receiver overload sensitivity, eliminating the need for an external attenuator. The
22G2-U/22G3-U
/22G4-U
OLIU can be used in place of the 22G-U in all
applications.
22G-U/22G2-U/22G3-U
/
22G4-U OLIU Faceplate
Indicators 7
The 22G-U/22G2-U/22G3-U
/22G4-U
OLIU circuit pack faceplate indicators are
shown in Figure 7-43.
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 22G-U/22G2-U/
22G3-U
/22G4-U
OLIU to accept fiber terminated with ST , SC, or FC connectors.
The 22G-U/22G2-U/22G3-U
/22G4-U
OLIU comes with a 0 dB ST buildout. For
the 22G-U, a 10 dB attenuator is required for loopback testing. The 22G2-U/
22G3-U
/22G4-U
does not need an external attenuator for loopback testing. The
22G-U/22G2-U/22G3-U
/22G4-U
OLIU operates over single mode fiber. Various
combinations of buildout attenuators and connectors are also available. See
Chapter 10, "Technical Specifications," for a list of universal buildout attenuators.