Specifications

4-92
Reference Guide
Model No.
Running Head
Redundant Operations System Configuration and Operation
4.24 Redundant Operations
This section describes the redundancy features of the integrated access system, and provides
instructions for configuring the system with redundant elements.
The integrated access system can be configured with redundant (backup) critical system
elements. This feature switches operation from failed components to identical backup
replacements, thereby reducing the likelihood of service disruptions.
The four areas of redundant operation are the power system, the CPU card, WAN card, and
ADPCM cards. These are described below.
4.25 Power Supply Redundancy
Each power supply component is designed to switch to a backup if a primary unit fails. Also,
the defective unit will create a system alarm upon failure, to alert an operator so that the
necessary diagnostic and repair work can be initiated. The following power supply
components can have redundancy:
AC Power Supply
DC Power Supply
AC/DC Converter
Ringing generator (master only; see below)
Upon failure, the LED on the AC-DC power converter will be turned off but
will not generate
a system alarm
(unless the system is equipped with the ALR 4+3PF Card (External Alarm
card).
If the primary ringing generator fails, an alarm will be generated and the LED will turn off. If
a backup ringing generator fails, the LED will turn off but no alarm will be generated by the
system.
Figure 4-62 shows a System Main Screen with redundant power supplies, in which Power
Supply 1 (PS1) has failed. The power supply failure is noted in the alarm message
PS1 OOS
in the upper right corner of the screen.