ADTRAN Atlas 550 - Manual (Page 42)

Chapter 2. Installation
2-6 ATLAS 550 User Manual 61200305L1-1
Alarm Relay Connection
This connection alerts the user when a selected alarm condition exists. The
four-pin, removable terminal block connects with external wiring. To make
the appropriate connections, remove the block, connect wiring as needed,
and return the terminal block to the connector socket. Clear the alarm con-
dition by pressing the Alarm Cut-Off (ACO) switch located on the font panel
of the ATLAS 550.
Table 2-4 shows the pinout for the Alarm Relay connector.
External Alarm Relay Monitor Connection
This connection alerts the user when a selected external alarm condition ex-
ists. This connection could be used to monitor a UPS with dry contacts or an-
other ATLAS 550. The two-pin, removable terminal block connects with
external wiring. To make the appropriate connections, remove the block,
connect wiring as needed, and return the terminal block to the connector
socket. Clear the alarm condition by pressing the ACO switch located on the
front panel of the ATLAS 550.
After the appropriate connections have been made, tighten the
screws using a flathead screwdriver before reinserting the terminal
block into the rear panel of the ATLAS 550.
Table 2-4. Alarm Relay Connector Pinout
Pin Name Description
1 Normally Closed (NC) Opens when a selected alarm condition
is present.
2 Normally Open (NO) Closes when a selected alarm condition
is present.
3 Common (COM) Common connection between external
circuitry and NC or NO terminal.
4 Chassis Ground (GND)
After the appropriate connections have been made, tighten the
screws using a flathead screwdriver before reinserting the terminal
block into the rear panel of the ATLAS 550.