XT2640 Operating Manual
13 July 2016
Page 127 of 187
A binary file is nominally 3x smaller than the equivalent ASCII file so more data can be written into the maximum
allowed data log file size of 4Gbytes.
A binary file typically has a 3:1 faster writing speed than the equivalent ASCII file, allowing shorter intervals to be
used when logging to a slower drive.
Although the binary file is limited to 4Gbytes in length, the resulting ASCII file may not be limited to this if it is
saved in the supplied application to a drive which does not use the FAT32 format (most computer hard drives use
NTFS or later formats which do not have this 4Gbyte limitation).
The FILENAME button allows you to set the name of the file which will be written.
Only filenames using the 8.3 form are allowed.
The extension is automatically provided (either .CSV or .BIN depending on the FORMAT setting).
The following file names may not be used –
VHLIMIT.CSV
AHLIMIT.CSV
CUSTOM.CSV
The HEADER button allows you to select if the file will start with a header record or not (this is only available for the ASCII FORMAT
setting).
If a header is set to be included, then the first file record will contain a textual description of each column of data.
Recommendation:
It is recommended to always include a header. In this manner if the file is inspected at some later date it is not
necessary to remember what each data column corresponds to.
The APPEND FILE button allows you to select what will happen if the specified file already exists on the drive when data logging is
started (or the drive is subsequently inserted after starting it).
Recommendation:
APPEND should only be selected when it is definitely known that the existing data has the same format. If set to
append to an existing file then the existing contents of the file may not be of the correct format to allow the file to
be opened on a computer after completing the data log.
23.7.2
CONFIGURING
DATA
LOGGING
TIMING
This is performed by using the buttons in the TIMING Area.
The START DELAY button allows you to select if actual data logging is to start after a delay has expired following pressing the START
button.
In the data entry screens for START DELAY there are four entries, one for each unit of days, hours, minutes and seconds.
The screen always starts with the days data selected; you can jump to any of the four entries directly by pressing the
respective entry area.
You can enter a numeric between 0 and 99 into any of the four entries. The actual time used is the total time created by
combining all four entries with their respective units.
When the ENT button is pressed the selected entry area automatically changes to next entry to the right, unless the seconds
entry is selected when the action is same as pressing the overall RETURN button.
Pressing the RETURN button returns to the Data Logging Configure Screen and saves the configured time, whereas
pressing the CANCEL button returns to the Data Logging Configure Screen without saving any changed data.
The RUN TIME button allows you to select if data logging is to run until manually stopped (MANUAL) or to run for a specific period of
time. If set to run for a specific time then the entry of that time follows the same procedure as setting the START DELAY (above).
The INTERVAL button allows you to set the data logging interval. The entry of the interval follows the same procedure as that for the
START DELAY and the RUN TIME (above), but uses a different set of four entries (hours, minutes, seconds, and 1/100
th
seconds). If
an interval time of 0 is entered then 0.002 seconds is used.
23.7.3
CONFIGURING
DATA
LOGGING
RECORD
CONTENTS
This is performed by using the buttons in the DATA area.
The TIMESTAMP button allows you to select if each record is to contain the time of day and date information, or not.
The first data of every record is always the record number which continuously increments.
If enabled, the time of day is the second data of every record and in ASCII format it is formatted as the prevalent time
format setting for the XT2640 (i.e. 12 or 24 hour format).
If enabled, the date is the third data of every record and in ASCII format it is formatted as the prevalent date format setting
for the XT2640 (i.e. DD:MM:YYYY or MM:DD:YYYY).
Recommendation:
It is recommended to always select that a timestamp will be included, otherwise you will have no record of when
a data log file was actually generated.
The SELECT DATA button allows you to select each of the 16 data selections which will be logged. The lower half of the button
shows how many data in total (including the record number and any timestamp information) will be generated by the present
selections for the SELECT DATA and TIMESTAMP settings. For the ASCII format, each data is typically 12 bytes of storage, otherwise
each data is exactly 4 bytes of storage.
