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Installation Manual LOGS50 EN_MI_090221
instead of a triggered one. That means that when the task has to be executed
because the time repetition pattern has arrived, the system will check if the
event
is “true” or “false” being only executed if it is “true”. In this case, transitions
are not taken into account only the static value of “true” and “false”, i.e., The
system do not check if the event goes to “false” before being in “true” state; only
checks if it its “true” or “false”.
The fact that date and time within the unit were incorrect does not prevent the
system for completing the tasks (after GSM/GPRS data sending, the unit
always synchronizes with the PC). The only reason for the tasks not to be
completed is that any of the following data be incorrect or incoherent:
manufacturing data, administrative data and configuration data.
It is important to take notice that there are certain actions incompatible among
themselves like BT communication while the iLOGS46 unit has its
communication window open. The reason of this incompatibility is that by
means of both serial and GSM/GPRS connection, the user can for instance,
modify the logger configuration. The incompatibility is resolved by giving always
maximum priority to BT connection over other connections.
On the other hand, must be taken into account that all the internal variables
whose change of state or variation are alien to the execution of tasks, internal
voltage, connector presence, temperature, are updated in each program
iteration, except for the temperature which is updated once per minute.
Next are described the tasks carried out by the logger:
2.1.1. READING TASK
Both digital and analog variables can be read. These variables can be either
local or remote (via RS485 Modbus RTU communication). The fact of reading
variables automatically implies an update in the values of the registers
associated with those variables. It is not necessary to program readings of
internal variables since they update with every program loop. It is not necessary
either to program the reading of digital totalizer and frequencymetre inputs since
they update with every pulse. It is possible to read analog remote variables with
different sizes, like 1, 2 or 4 bytes. As communication with remote elements is
made by RS485 with ModBus RTU protocol, the reading of remote values is
also realized from remote ModBus registers that have the size of 2 bytes. The
differentiation between different formats of variables takes place in the
configuration thanks to the field called “number of bytes”. In all cases, the
information received would be represented as float.
2.1.2. REGISTER OR LOGGING TASK
It is possible to record any variable: internal, analog or digital, remote or local. It
is necessary to program a reading task of the variables to be registered before
recording them, since a recording task does not imply by itself a reading of the
variable prior to its recording in FLASH memory. It is also important to know that
the information stored in the data history must have the same format in order to
