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 2-9
Intraplex Products
Table 2-1. CM-5RB Indicator Lights (continued)
Light Description
CPU
(red) Central processing unit of CM-5RB module
ON A microprocessor or memory fault has been detected on CM-5RB module. CPU failure is
reported as an alarm to shelf alarm circuitry. This light turns on briefly at power-up.
2.1.4 Redundancy
ACS-160 Series multiplexers can have two levels of redundancy:
● Module redundancy – Two CM-5RB modules are installed and, if the primary one fails, the backup
module takes over.
● Module and line redundancy – Not only are two CM-5RB modules installed, but two T1 lines are
also connected. The system is protected against either the primary CM-5RB module or the primary
T1 circuit failing.
2.1.4.1 Redundant CM-5RB Module Operation
The CM-5RB module installed in front of the MA-235-1 module adapter assumes the role of “Primary
CM.” The CM-5RB module installed in front of the MA-235-2 assumes the role of “Backup CM.” During
normal operation, both primary and backup common modules transmit the same T1 payload data
through both the primary and backup lines. Only one common module, the “Active CM,” is used at a
given time to receive T1 data. The common module not being used to process received T1 data is
called the “Standby CM.”
● Primary : The CM-5RB module installed in front of the MA-235-1 module adapter.
● Backup : The CM-5RB module installed in front of the MA-235-2 module adapter.
● Active : The CM-5RB module passing received T1 data.
● Standby : The CM-5RB module not passing received T1 data.
Based on the switching of a particular system, either the primary or backup CM-5RB module can be
the Active common module. At initial system start-up, the primary CM-5RB module is automatically
set as the Active CM.
The primary CM configured for terminal or DI-A mode automatically turns on in the Primary role. While
in this role, the primary CM constantly searches for backup CM-5RB modules on the shelf and, if it
finds one, periodically reports status to backup through the multiplexer bus, including
● Mode.
● Hardware status.
● Line status.
Note: The process of transmitting shelf data from a Primary to a Backup CM-5RB module can be
slow. With a full shelf of 18 modules, it can take up to two full minutes for the Primary CM-
5RB module to transmit an entire shelf image to the backup CM-5RB module.
The backup CM-5RB module monitors the report from the primary CM. If the report fails to arrive, or if
the report indicates a hardware failure or a line failure, the backup CM compares the report to the
switching criteria set in the REDN group (Section 4.6 –
Redundancy Configuration Group (REDN) ). If
the failure and switch criteria match, the backup CM module takes control of the MA-215 module
adapter. A signal generated from the module adapter takes the failed primary CM off the multiplexer
bus.
In a drop and insert multiplexer, the primary CM-5RB module in the DI-A mode holds the channel
module configuration information; the DI-B CM-5RB module does not hold this information. The DI-A
CM-5RB module queries the DI-B CM-5RB status and reports it to the DI-B backup CM-5RB module
(Figure 2-7). The DI-B backup CM-5RB module then takes appropriate action. Since DI-B CM-5RB