The fan tray includes an alarm port that maps to 4 dry contact alarm inputs.
The pins on the alarm port are passive signals and can be configured as Normally Open (an alarm generated when current is
interrupted) or Normally Closed (an alarm is generated when a circuit is established) alarms. You can configure each alarm
input as critical, major, or minor. An alarm triggers alarm LEDs and alarm messages. The relay contacts can be controlled
through any appropriate third-party relay controller. The open/close configuration is an option controlled in IOS.
To comply with the Telcordia GR-1089 NEBS standard for electromagnetic compatibility and safety, connect the alarm ports
only to intra-building or unexposed wiring or cable. The intrabuilding cable must be shielded and the shield must be grounded
at both ends. The intra-building port(s) of the equipment or subassembly must not be metallically connected to interfaces
that connect to the OSP or its wiring. These interfaces are designed for use as intra-building interfaces only (Type 2 or
Type 4 ports as described in GR-1089-CORE) and require isolation from the exposed OSP cabling. The addition of Primary Protectors
is not sufficient protection in order to connect these interfaces metallically to OSP wiring.
Only Pins 1, 2, 4, 6, and 8 are available for customer use. The remaining pins are for Cisco manufacturing test, and should
not be connected. Use a shielded cable for connection to this port for EMC protection. External Alarm Input Pinout table summarizes the pinouts on the alarm port in the Troubleshooting section.
For information about how to map alarm inputs to critical, major, and minor alarm conditions, see the Cisco NCS 4216 Software Configuration Guide.