Televes OLT 769401, User Manual

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The Global parameters table is composed by the following parameters:
Parameter Description
Quality level May be enabled or disabled
Active Source
Synchronization source (slot or junction number) of the respective PLL;
PLL Status
Equipment system PLL is controlled by a state machine according to G.781 recommendation
and can have one of the following status:
Hold Over
: The PLL will switch to this status if it ceases to be a valid synchronization source.
This status provides a stable synchronization clock based on the original clock memorization;
Free Run : The PLL is synchronized by the local clock;
Normal
: The PLL is synchronized by the programmed synchronization source
Lock alarm This alarm is triggered when the PLL is not locked
Command
There are several external commands that are available to the user, for example for
maintenance purposes commands. These commands are independent and have different
impacts on the selection processes.
Enabling and disabling external commands associated with the synchronization selection
process is defined below. Only one of these external commands is enabled by the selection
process at a time.
It is possible to carry out the following commands in the active synchronism sources, by
selecting the command in the combo box and clicking on send
Clear
Manual Switch
Force Switch
Table 6-3: Global Parameters
In the Synchronism Sources table, it possible to view the Physical interfaces that provide synchronism to the system which junctions
are indicated in the Source column (in case of interfaces, the number of the slot to which the interfaces belongs is indicated)
Parameter Description
Source Indicates synchronization source (slot or junction number)
SSM Rx
This column identifies the received SSM (Synchronization Status Message);
SSM Used This column identifies the used SSM
Signal Fail
Signal failure of the respective synchronism source
Attenuation
Attenuation (measured in dB) associated with each of the existing synchronism junctions
Command
It is possible to temporarily remove a synchronism source attached to a selection procedure. This is
controlled via the Lockout command. This command is accepted for synchronism sources enabled
in each selection process. The lockout state of a disabled synchronism source is “off”. However a
synchronism source that is locked out, remains named for the selection process and maintains its
priority.
It is then possible to perform the following commands at the synchronism source level by selecting
the command in the combo box and clicking on send
Clear
Lockout
Table 6-4: Synchronism Sources parameters
Use of external Commands in Global parameters table and Synchronism sources table:
Clear (at Synchronism Source table):
The Clear command removes the Force Switch and Manual Switch commands (Global Parameters table), by turning “off” the
Lockout state of a synchronism source. This allows synchronism source availability for selection process;
Lockout
(at Synchronism Source table):
If the source is in “Lockout”, the user will never be able to execute “Force Switch” or “Manual Switch” (Global Parameters
table) for this source. This command turns “on” the Lockout status of a synchronism source. This allows synchronism source
unavailability for selection process;
Manual Switch
(at Global Parameters table):
Enables switching to the selected synchronism source if it has no failure.
This command selects one synchronism source by assuming it is enabled, is not Locked Out, is not in signal failure
condition and has a QL (Quality Level) higher than the other synchronism sources and then the synchronism source