Harris ACS-163, Руководство по установке и эксплуатации

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2 – Functional Description ACS-160 Series & STL-160 Series T1 Multiplexer Installation & Operation
Version 2.11, August 2011
Harris Corporation 2-5
Intraplex Products
Figure 2-5. Mean Time to Lose T1 Frame Synchronization
Once frame synchronization is achieved, the demultiplexer develops the proper demultiplexing bus
signals and feeds them to all the channel modules plugged into the shelf. Bus signals include
● Demultiplexed channel data.
● Demultiplexing synchronization status.
● Synchronization signals necessary for proper decoding by the channel modules.
2.1.3.5 Loopback Configurations
The CM-5RB common module provides three loopback options (Figure 2-4):
● Line – Use the line loopback to test the transmission path integrity and the T1 connections to the
multiplexer. This loopback takes the decoded T1 receive signal coming from the line receiver/jitter
buffer and loops it back to the T1 line driver input. Receive data also passes on to the
demultiplexer.
● Payload – Use the payload loopback to verify CM-5RB module operation up to the bus interface to
the channel modules. Data also passes on to the receive side of the channel modules.
● Equipment – Use the equipment loopback to test individual channel modules in the multiplexer.
It loops the transmit signals at the multiplexer output back to the demultiplexer input. During
equipment loopback, the T1 output of the CM-5RB module is an all-ones signal.
Section 5.2.3.2 – Shelf-Level and Common Module Remote Access gives more information on
loopbacks.
2.1.3.6 Microprocessor Control and Battery-Backed Memory
The microprocessor chip used on all Intraplex common modules contains a lithium battery, which is an
inextricable element of the microprocessor and is not independently replaceable. The lithium battery
powers the memory on the chip and thus retains setup information whenever operating power is
removed, which might occur at any of these times:
● When equipment is stored or in transit
● When the module containing the chip is removed from a powered shelf
● When there is a temporary loss of power, other than unintentional or catastrophic
In the design of Intraplex equipment, battery failure does not affect proper operation while the
equipment is under operating power. Battery failure does not become evident until power is removed
and the equipment is subsequently repowered. Upon repowering, the alphanumeric display on the
common module flashes “ERR 0” or remains blank.