User Manual

SGD-SB2025NT-TUM, Part 2
Jan 12 Page 90 ALARMS
Figure 79. Alarm on the NI Environment page.
12.5 TM D UPLICATION A LARMS
12.5.1 Alarms on a Secondary TM
Just as for the other parameters in the Secondary TM, the definition of alarm events will be taken
from the Primary TM; they cannot be different to the Primary TM or defined at the Secondary TM.
However, alarm events must be acknowledged at each TM independently.
When the Primary TM has been configured to generate alarms, if the Secondary TM subsequently
experiences an alarm event whilst offline, it will not have control of the Central NI and, therefore, is
unable to generate the external alarm function to indicate a problem. Similarly, monitoring for
alarms will be conducted through the Primary TM, consequently, an alarm on the Secondary TM
will again go unnoticed.
12.5.2 Indicating an Alarm from an Offline TM
The problem of not knowing of an alarm on an offline Secondary TM is handled by the Secondary
TM ceasing to communicate with the Primary TM. This will cause the ‘Duplication’ fail indication on
the Primary TM to be activated, therefore, it is imperative to ensure that the ‘Duplication’ alarm is
enabled so that the external alarm indication will operate.
If this situation arises, the first action will be to acknowledge the ‘Duplication’ alarm on the Primary
TM and then attempt to access the Secondary TM to examine and acknowledge the alarm. If
remote access to the Secondary TM fails, this will indicate either a total failure of the Secondary
TM unit or a network fault. If access into the Secondary TM is successful, the alarm can be
acknowledged as described earlier and any appropriate action taken.