Cisco Gigabit Switch Router 12008 Installation And Configuration Manual page 73

— DB-25 alarm contact connector—A female DB-25 D-sub connector incorporated
into the CSC faceplate enables you to attach an external alarm monitoring facility
to the router, thus supporting a telco style of handling alarm conditions in the router.
The alarm signals sent to this DB-25 connector are identical in function to those
sent to the system LEDs on the CSC faceplate (see the following section entitled
"System Alarm LEDS").
Any alarm condition in the router that activates one of the system alarm LEDs on
the CSC faceplate also energizes an appropriate CSC relay, causing a corresponding
signal to be sent to the DB-25 connector. If an external alarm monitoring facility is
attached to the DB-25 connector, this signal activates the appropriate external
audible or visible alarm.
An external audible alarm can be reset by clearing the condition that caused the
alarm or by pressing the alarm cutoff reset/lamp test (ACO/LT) button on the CSC
faceplate (see the following discussion about the ACO/LT button). A visual alarm,
however, can be reset only by resolving the problem that caused the alarm
condition.
Only safety extra-low voltage (SELV) external alarm circuits can be connected to
the DB-25 connector.
— One external closure sense line, enabling the router to monitor an external event,
such as the opening of a cabinet door or the activation of an alarm in associated
equipment.
— Alarm cutoff reset/lamp test (ACO/LT) button—If you equip your system with an
external alarm monitoring facility, a visible indication can be provided, and/or an
audible alarm can be sounded, to immediately notify site personnel of an alarm
condition in the router.
An audible alarm generated by the system continues to sound until you either clear
the alarm condition itself or press the ACO/LT button to silence the alarm. Merely
pressing this button does not resolve the alarm condition.
You can test the operability of the LEDs on the CSC(s), the SFC(s), and the power
supply(ies), by pressing the ACO/LT button at any time. Doing so causes the LEDs
on all these router components to remain lit as long as you hold down the button.
However, the LEDs on the SFCs are visible only when the air filter assembly is
removed.
Overview of the Cisco 12008
Product Overview 1-51