ADTRAN Total Access 850 System Manual page 263

Total Access 850 System Manual
2. Alarm relay contacts are open during normal operation. The alarm relay contacts close in the event of
a local alarm condition or the receipt of an alarm from the T1 Carrier.
3. In a carrier alarm condition such as a Red, Yellow, or Blue (unframed all 1s), various alarm contacts in
the PSU close.
4. Carrier alarm conditions cause the Total Access 850 to initiate trunk processing. The following chain of
events then occur:
• MJ will be directly shorted to MJR.
• MJV will be directly shorted to MJVR.
5. Contacts MJ and MJR can be overridden manually during an alarm condition by pressing the ACO
pushbutton on the PSU faceplate.
6. If the 3-Amp power fuse on the PSU trips, the -48 ALM relay will close, providing a -48 VDC signal on
that pin. This alarm cannot be overridden by the ACO pushbutton. Refer to the table below for alarm
notifications.
RED ALARM
YELLOW ALARM
AIS ALARM
PSU POWER FUSE FAILS
ALARMS ACO
DEACTIVATES
Note: ACO will not deactivate MJR after a power fuse
failure.
64203376L1-1B
Alarm Condition
© 2004 ADTRAN, Inc.
Relays Activated
MJR MJVR -48 ALM
X X
X X
X X
X X
X X
Section 5 DLP-16
P7
P6
X
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