Specifications

Reference Guide 5-9
Interface Card Using the Node Port
Figure 5-7. Component Layout for the INF+M T1E1*8 and INF T1E1*8 Interface Card
5.4 Using the Node Port
The Node Port allows the system to report ACO (Alarm Cutoff) alarms to an external system
to alert the operator to critical situations. Using the ACO function, keeps the alarm active until
manually cleared from the terminal.
The node port uses an Rj48 connector. Pins 3, 4, and 5 form an RS485 compatible c-contact
closure that can be used to report ACO alarms to an external system. Pins 1, 2, 6 and 7 are
reserved for future use. Pin 8 is ground.
Connection of the ACO alarm interface to an external alarm device (such as a buzzer or light)
alerts you to problems with the system. Figure 5-8 shows a possible configuration connecting
a unit to a generic external alarm system. The nominal input is 5V and the short-circuit current
is 250mA.
The alarm interface is activated by the ACO setting. This will activate the device when a
designated alarm occurs.
Modem Line
(no modem on 8921)
Nodal Port
VT-100 Control Terminal
DB-9 Serial Port
Amphenol Connector
for WAN Connections
Power
Bus
Edge
Connectors