LSI LASTEM M-Log – User’s manual
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5.1.2
Checkimg the power supply voltage
During the survey the instrument checks the power supply voltage constantly, in order to grant its
enough to the inner functions. The check isn’t arranged to grant the operation of the outside devices
(modem, sensors that need power supply, etc.) that already couldn’t work regularly.
The check happens every minute: the instrument acquires and checks the power supply voltage; it
must be 3,5 Vdc at least. In case it isn’t enough, M-Log closes the survey in progress and stands by.
During the stand-by it checks every minute the power supply voltage, until it’ll reach the minimum
value of 3,7 Vdc. The note “Power low” (instead of the measures list) shows the stand by condition
looking forward the right power supply. When the right voltage comes back, the survey’s re-opened
and the standard operating modes re-start.
Note: the power supply voltage is acquired and checked, even if the instrument’s configuration
doesn’t include (among the programmed measures) the corresponding acquisition measure of the
battery’s voltage. In order to store the feeding values (surveyed during the survey), the battery
voltage measure must be programmed (like proposed by
3DOM
warning message).
5.2
Acquisition and calculation of measures
It is possible to acquire measures of sensors with a rate from 1 second to 12 hours; this allows a
better representation of both fast-changing quantities (wind speed), as well as slow-changing ones
(air temperature). It is possible to acquire as many as 10 measures per second.
For sensors which have to be powered, M-Log is fitted with own outputs with switched power
supply (
actuators
).
The instrument is able to calculate quantities deriving from measures that sample the signs from the
inputs: M-Log is fitted with a calculation library dedicated to environmental applications, also able
to carry out useful mathematical functions (see §
Errore. L'origine riferimento non è stata
trovata.
). M-Log is able to acquire and calculate up to a maximum of 50 total measures.
Furthermore it’s possible to program some calculated measures according to the data generated by
other calculated measures.
Program
3DOM
can be used to program the measure sampling sequence: the program interface
allows choosing the sequence in which the measures are displayed; hence which is the sampling
sequence taking place during the survey. With
3DOM
you can also set automatically the measure
sequence according to their acquisition rate (from the shortest to the slowest). This is important to
gather measures which, during the acquisition process, must be sampled within the shortest
intervals possible among each other (if they are allocated to only one actuator).
If configured with the same acquisition rate, the analogue channels following the first one will be
sampled about 80 ms after the previous channel. This means that as many as eight analogue
channels are sampled within a total time of 400 ms. Digital channels are instead sampled in about a
flash. In case of application with a sensor with two measures that requires an actuator, remember
that the probe must be connected on 1-2 inputs (actuator n.1) or on 3-4 inputs (actuator n.2).
