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OBSERVATOR
Instruments
Technical User Manual
OMC-045-II
6.2.3 Scheduling Input task
If a task doesn’t get its data on time, a time out will occur. When a timeout occurs the “power switch” will
be switched off and on. In case the task doesn’t make use of a “power switch”, only the task will be reset,
the task is rescheduled. If the interval is smaller than 5 seconds, then the task will be put on 5 seconds for
only one time, after that it takes it normal interval again.
6.2.4 Scheduling Output task
Depending on the system, if it is in “Alarm mode” or not, the interval of the task is synchronized with the
clock of the OMC-045-II. There are no timeouts on an output task. Timeouts are only copied from an input
task. The output drivers only use data that is received from an input driver. If the data is not visible,
because a timeout had occurred, it will show in the data that there was a timeout.
If the “Operating mode” from a system is set on “Low power”, the output drivers will react different then
when the system is on “Full power”. In a “Full power” system, the actual data is used as long it is made
available. In a “Low power” system, the output driver will wait until all data is made available by the input
drivers. The data is available if it is refreshing or has a time out status.
Warning:
An output task is been delayed if the data is not available, in “Low power” mode.
6.2.5 Scheduling Editing task
Example, the operator edits the configuration for the calculation of the average of a measurement and
sets it to 10 min. The scheduler then knows that the data from the average driver is available after 10 min.
The scheduler takes this in account when the task starts for the first time. This is the “Time to result”. By
scheduling the task, the scheduler takes in account, that some have a calculation period. In that period
the scheduler knows that he cannot sample the data and samples it after the calculation.
6.2.6 Synchronization Editing and output tasks
If an editing task is configured, the data will most likely be used by an output task. To make this all work
smoothly, it’s important to make a smart choice about the output intervals.
If the shortest output interval is (for example) 15 min and the average calculation interval 10 min, the
average calculation driver would be activated every 10 min of every 15 min. This is a smart way to
synchronize, when the OMC-045-II is in the low power mode, because, for the other 5 min, the system
can go to sleep mode and saves power. This means that in one hour the system only wakes up 4 times
for 10 min and sleeps 4 times for 5 min. So the system sleeps 20 min every hour and works only 40 min
every hour. This can save a lot of power.
Power Delay
Measuring/ calculating average
Low Power
Wake up
Save data
Go to sleep
Start measuring and calculation average
