Mitsubishi Electric MELSEC iQ-R Series User Manual page 13

Considerations for data logging, event logging, and report functions
■Data logging, event logging, and report functions
• The data logging, event logging, and report functions are best effort functions. Since the processing time of a module varies
depending on the setting and the status of other devices, these functions may not perform at the set sampling interval. Run
the system by fully verifying the processing time of each function when constructing it. For processing time, refer to the
following:
(Page 344 Processing Time)
• If data logging function, event logging function, or report function are used, they affect the sequence scan time of the
access target CPU module. Run the system by verifying how the sequence scan time is affected when configuring the
system.
(Page 352 Influence on the sequence scan time)
• If exponential format is selected for the data output format with the data logging, event logging, or report setting, rounding
errors will occur in the range of the number of digits that exceed the number of digits set for the decimal part.
• If the result of the linear function transformation with the scaling function exceeds the maximum or minimum range of the
specified output format, the maximum or minimum value will be output in binary format. Therefore, when outputting in the
binary format, errors may occur in the output values.
• The file transfer/e-mail transmission via the file transfer function/e-mail function may take from a few seconds to tens of
seconds depending on the network line or transmission size. Target files may be deleted before file transfer/e-mail
transmission is completed depending on the settings. Review the file switching timing and the setting for the number of
saved files and lengthen the time until the file is deleted.
( Page 51 File switching timing)
• When a CSV file is opened with Excel
format as necessary.
• Since general sampling specified data and report current value data are sampled asynchronously with the sequence scan,
data separation may occur. If data separation must be prevented, set the number of device points sampled at one time to
less than the access units, or set the module to use high speed sampling.
■Data logging function
• When the number of device points to be sampled by the trigger logging function exceeds the access units and general
sampling is specified for the data sampling method, device values sampled in another sequence scan as the one where the
trigger occurred may be included in one data row. To avoid this, the number of device points that can be sampled at once
should be less than the access units or high speed sampling should be used. For the access units, refer to the following:
(MELSEC iQ-R High Speed Data Logger Module User's Manual (Startup))
• Immediately after switching the programmable controller system ON, if a trigger occurs before sampling the number of lines
of data before the trigger, the lines of the data before the trigger may be fewer than the specified number of lines.
• When triggers continuously occur with the trigger logging function, triggers may not be detected or the number of lines of
data specified before the trigger may not be output. For operation when triggers continuously occur, refer to the following:
(Page 29 Trigger logging function)
■Report function
• Immediately after switching the programmable controller system ON, if a creation trigger occurs when data does not exist in
the data logging file, an error occurs in the high speed data logger module. Configure and construct the system so that the
creation trigger occurs after data is saved in the data logging file.
• Report output takes time. Therefore, according to the data logging save setting, the data logging file including the data
when the creation trigger occurs, may be deleted before the report output is completed. In this situation, the specified
number of records worth of data is not output, and an error occurs in the high speed data logger module. Check the Point in
the following section when configuring and constructing the system.
(Page 74 Creation trigger function)
• When the creation triggers continuously occurred, they may not be detected. For operation when the creation trigger
continuously occurred, refer to the following:
(Page 74 Creation trigger function)

, the date column format is displayed in the default setting of Excel. Set the cell
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