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Chapter 3 ’Web Browser Interface’ — Interface Description
136 Amethyst III DTV Smart Switch
User Manual
Figure 3-83. Persistence: examples
Alarm without persistence
Alarm with persistence:
o
duration 1s,
o
upper threshold 1,
o
lower threshold 0.
Alarm with persistence:
o
duration 1s,
o
upper threshold 2,
o
lower threshold 1.
0.5 0 1 1.5
When having a delay between input streams, there may be a delay
between a problem detection on both inputs, thus resulting into a
useless switch.
To avoid this switch, do not use persistence but time delay (see the
Section ’Switch Item (ASI or IP)’ on page 126) for taking into
account the delay between the inputs.
The possibility of persistence configuration depends on the tests.
Different configurations are listed hereafter.
Persistence Configuration
Persistence configuration can be:
 Mandatory: you must set the parameters.
or

Optional: you can set the parameters. To do so, check the box.
For both cases, there are two levels of configuration:
 Duration only: you must set the duration, between 0 and 1 second.
Figure 3-84. Persistence: duration configuration only
Mandatory
Optional
 Full configuration: you can set not only the duration but also the upper
and lower thresholds of number of errors.