A8814 Acq
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will be displayed along with the file size and timestamp when the file was last modified.
Each modbus device may have multiple log files. The log file name starts with “mb-xxx.” where xxx is the
modbus device id number. One file, with the .log extension is the file where the most recent data is being
stored. Other log files have a .gz extension. These are older log data files that have been compressed to save
space.
The file name will be a link that will open up a browser window to view the contents of the single log file.
Clicking on the single log file will only show the contents of that log file, and not all historical data for the device.
Use the log export feature if all log data is required.
Log File Format
Once you have downloaded the data from the AcquiSuite, you will need to process it. The file is an ASCII text file
with comma delimited data. One line is recorded for each log cycle. The file will look something like the following
example from a 4A4P-M IO Module.
'2002-01-31 18:30:00',0,0,0,-0.00,89.29,39.05,49.11,0,0,0,0
'2002-01-31 18:35:00',0,0,0x02,-0.01,104.24,39.05,49.11,0,0,0,0
'2002-01-31 18:40:00',0,0,0,,87.82,39.05,49.11,0,0,0,0
'2002-01-31 18:45:00',139,,,,,,,,,,
In this example, the first line shows a regular log entry. The second line shows a high range alarm for data point
2. The third column shows point 1 as invalid, and the fourth line shows the Modbus device is not responding.
Notice the following columns are shown.
1.
Date/Time in UTC (GMT) time. This field is quoted to handle the space in the middle.
The format is YYYY-MM-DD HH-MM-SS
2.
Modbus error (if any). 0=no-error, see table below.
3.
Low Range alarm bitmap (hex notation).
4.
High Range alarm bitmap (hex notation)
5.
Data point 1
6.
Data point 2
7.
- - -
8.
Data point N
Comments:
Date/Time:
The date/time column reports the time at which data was logged from the Modbus device. Note:
this is not necessarily the time at the start of the log cycle. Users with large number of devices may notice some
of the Modbus devices at higher address numbers report 1 or 2 seconds after the first Modbus devices. This is
because the 9600baud speed of the Modbus loop is not fast enough to log all Modbus devices in less than 1
second. If a device does not respond during a log cycle, the AcquiSuite will attempt to query the device several
more times. If a subsequent query is successful, the time of the successful query will be used in the log file but
may be several seconds after the initial log cycle.
The log date/time is in Universal time. (UTC) This means that the data is logged with no shift for daylight savings
time, and must be converted to local time for reporting purposes. When importing into a database, data should
be kept in UTC time for ease of use. When reporting the final data, you should adjust the time to reflect the local
timezone for which you are reporting. The data export option on the BMO website will prompt you for a
timezone when you export the data, and will adjust the log date/time accordingly. Note: UTC is sometimes
referred to as GMT. (Greenwich Mean Time)
