External Alarms Connections - Cisco Prisma II Installation And Operation Manual

External Alarms Connections

Master/Slave Operation
All Prisma II modules ship from the factory configured as a "Master." The ICIM, the
LCI, or TNCS software can be used to reconfigure a module as a "Slave" or as
redundant. The Prisma II Chassis allows for local hard-wired redundancy by using
the ALARM IN and ALARM OUT connectors located on the connector interface
panel. You can configure a pair of modules so that if the master fails, the slave takes
over by using the ALARM IN and ALARM OUT connectors.
ALARMS IN and ALARMS OUT Connections
The Prisma II Chassis provides two connections for external alarms to and from each
module slot. These alarm connections are located in two 37-pin D-connectors
(DB-37) and are labeled ALARMS IN and ALARMS OUT. See the section titled
Alarms Connectors in Chapter 2 of the Prisma II Chassis Installation and Operation
Guide, part number 713375.
When a critical alarm occurs in a master module, the master turns off and the slave
(redundant module) is enabled. To make that happen, the pin representing the
master module's slot in the ALARM OUT connector must be externally wired to the
pin representing the slave module's slot in the ALARM IN connector. Once those
contacts are wired, care must be taken to ensure that the master and slave modules
are not moved to other slots. Otherwise, the ALARM IN and ALARM OUT
connectors will need to be rewired to the appropriate pins.
Notes:
• Any device configured as a master ignores its ALARM IN contacts.
• To verify proper wiring and redundant configuration, simply unplug the master
device and observe that the slave module turns on. For detailed information on
ALARM IN and ALARM OUT connectors, see the section titled Alarms
Connectors in Chapter 2 of the Prisma II Chassis Installation and Operation Guide,
part number 713375.
ALARMS IN and ALARMS OUT Connector Illustrations
78-739260-01 Rev F Installation 2-15