E1 Input Module Alarm Modes - Symmetricom SSU-2000e User Manual

The E1 Input module also contains provisions for zeroing the phase readings for
one channel in response to a command from the Communications module. Once
the phase is zeroed, all subsequent phase measurements are expressed in terms of
how much they differ from the reading at the time the phase was zeroed.
Zeroing the phase invalidates all past phase averages, TDEV, and MTIE.
Sync Status Messages
The E1 Input module reads and processes Sync Status Messages (in accordance
with applicable parts of ITU-T G.781 and with T1X1.3 TR33, ANSI T1.101-1999, and
Telcordia Technologies GR-253 and 378-CORE) to determine the traceability of
inputs. This traceability information is then used by the Clock modules in selecting a
reference signal and is embedded into the system's outputs. For E1 inputs, an SSM
is valid if three consecutive matching SSMs are received.

E1 Input Module Alarm Modes

The E1 Input module responds to various alarm conditions according to user-set
alarm levels. Each level is associated with a set of actions (or non-actions) as
shown in Table
Table 7-1. E1 Input Module Alarm Modes
Alarm Mode
IGNORE Do nothing
REPORT Do nothing
MINOR Generate event message
MAJOR Generate event message
CRITICAL
SSM Selection Criteria
If the E1 Input module is configured for provisioned mode, it will use the provisioned
SSM. If configured for automatic mode, the Input module uses the most recent valid
SSM. If a valid SSM is not received, the module uses the provisioned SSM. Refer to
the SSU-2000e Technical Reference for more information on provisioning SSMs.
12713140-002-2 Revision E – October 2006
7-1.
Action
Generate event message
Fault Port
Chapter 7 Input Module Reference Data
1-Port and 3-Port E1 Input Modules
Alarm Elevation
Cannot be elevated to a higher severity level
Cannot be elevated to a higher severity level
Elevate to MAJOR if the alarm condition persists
beyond the user-set elevation time limit
Elevate to Critical if the alarm condition persists
beyond the user-set elevation time limit
Cannot be elevated to a higher severity level
SSU-2000e User's Guide 167