Obvius A7801 - Manual (Page 23)

Log File Data
The AcquiLite stores interval data in non-volatile memory. The system battery maintains this memory when the power is
disconnected. When the memory is 100% full, the oldest data records are overwritten by new records. The system can
store approximately 37 days of data when logging every 15 minutes.
Log File Status
The AcquiLite can display a list of log files in the "log file data/status" web configuration page. A bar graph will show the
amount of storage capacity that is used by the existing log data.
Log File Format
Once you have downloaded the data from the AcquiLite, 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.
'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,NULL,87.82,39.05,49.11,0,0,0,0
'2002-01-31 18:45:00',161,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL
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 time when the AcquiLite was rebooted.
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. Log 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 pulse input device.
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)
Error: If the error value is not 0, the remainder of the columns for this line will be reported as NULL.
160 Start log (Entry in log file after AcquiLite starts up)
161 Stop log (Entry in log file if AcquiLite is shut down properly)
162 System time changed, caused logger to restart logging for intervals.
163 System auto-restart
164 Log entry corrupt.
Low/High Range Alarms: This number is a hex representation showing which data points are out of range. 0x01 shows
data point 1 in alarm state. 0x04 shows data point 3 in alarm state.
Data Points: Data points are shown in the same order as the pulse input configuration display in the AcquiLite configuration
web page. Data is displayed in floating point form. When a specific point is unavailable (4A4P-M broken wire alarm) or the
point is not supported as part of the configuration (phase B current on a single phase H8163 meter hookup) the point will be
logged as NULL. This preserves the column structure of the file, and allows notation of invalid data. SQL databases often
accept NULL as a valid entry in a data table to represent invalid data.
Page 23 A7801 AcquiLite – Data Acquisition Server