Ltc 8901 Series Cpu Selection Switch - Bosch LTC 8900 Series Installation Manual

LTC 8900 Series
Connector
Positions
7 & 8
9 & 10
11 & 12
Table 6.4: CPU Relay Output Functions
6.17

LTC 8901 Series CPU Selection Switch

The Switch Control input to the LTC 8901 Series can be over ridden using the front panel
switch. This switch allows manual selection of either the primary or backup CPU. This switch
should be left in the AUTO position to enable the automatic switchover functions. The AUTO
LED on the front panel illuminates to indicate proper switch position. If the LTC 8943/95
System Controller PC is not connected, the CPU cannot operate in a redundant mode even if
its front panel switch is set to AUTO. However, the system will continue to operate in a
nonredundant mode because the communication signals to the matrix bays continues to be
supplied from the primary CPU.
If the CPU bay front panel switch is used to manually select a CPU, the appropriate LAN port
enabling must still occur. The System Controller performs this action, even if the front panel
switch is used to manually override automatic CPU selection. If the System Controller is
connected and the System Supervisor software is running, the System Controller will
automatically enable and disable the appropriate ports (when the System Supervisor software
is running, the Controller Activity LED on the front of the LTC 8901 Series CPU bay will be
blinking).
If a manual selection is made when the System Controller is not connected or the System
Supervisor software is not running, the installer must manually ensure that the selected
CPU LAN connection is plugged into an active port, and that the nonselected CPU LAN
connection is either plugged into a disabled port or unplugged.
Bosch Security Systems, Inc.
Hardware Installation Procedure for Redundant System Configuration Utilizing LTC 8901
Functions
Relay - Backup CPU Fault
Relay - Any Fault
Input - Silence Buzzer
Installation Manual
Description
Normal open, closes when Backup CPU
failure is detected
Normally open, closes when any LTC 8901
failure is detected
Connect these inputs together to silence
the LTC 8901 Series failure/warning
buzzers
51
Series CPU | en
2015.01 | 10.6 |