Albalá Ingenieros ASW3000C01, Руководство пользователя

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Albalá Ingenieros | Manual ASW3000C01
4.3.1.7. Useful load of the transport stream
The bitrate of the useful load of the transport stream is calculated by counting
every packet received during an interval of one second, multiplying this value for
188 bytes/packet and then multiplying by 8 bits/byte. The bitrate obtained is then
compared to thresholds that establish the minimum and maximum permissible
bitrates.
If the resulting traffic exceeds the maximum limit or falls below the minimum limit
then the traffic error condition is activated. This condition is updated in intervals of
one second each.
The factory-programmed values do not permit this error condition to occur:
minimum of 0 bit/s, maximum of 131Mbit/s.
4.3.1.8. A percentage of null packets above or below set thresholds
The number of null packets (PID equal to 0x1FFF) and the number of full packets
received during an interval of one second are counted and the ratio between them
is compared to minimum and maximum thresholds. This error condition is
activated if the ratio is above the maximum threshold or below the minimum.
The existence of null packets is required by some DVB systems.
The factory-programmed value will not activate this error condition: the minimum
value is 0% null packets and the maximum is 100%.
4.4. Operating modes
The ASW3000C01 has three operating modes: Automatic, Semiautomatic and manual.
The behavior of each mode is described as follows.
4.4.1. Automatic Mode operation
In this operating mode a series of priorities are established and at any given moment
the ASW3000C01 selects the highest priority input that does not have any error
conditions. The input priority is configurable and can set the Main input to the
highest priority and the Reserve input to the lowest priority, or the inverse can be
programmed.
Each time that the ASW3000C01 switches between inputs the FAILURE LED begins
blinking and an audible beep is emitted. To acknowledge the alarm indicator, the
RESET button in the Alarms box should be pressed. If the situation that caused the
alarm occurs again before the operator can acknowledge the first alarm, the module
will switch again. In either case, the alarm condition indicator will remain active until
it is acknowledged by the user.
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