Future Design MCT-MC 4.3, Руководство пользователя

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MCT-MC
4.3
Logging - 83 - FDC MCT-MC
The Interval (secs) field is used to set the rate at which points are written to the log file which equates to the
sample rate in seconds. When the “Fixed Interval” option is turned on, the logging interval will be automatically
set to record at minute intervals based on the number of days set for the file. If the file is set for 1 day in length,
the logging rate will be at 1 minute intervals. If the file is set for 7 days, then the logging rate will be every 7
minutes. This keeps the data file size manageable and able to be viewed by the MC data viewer.
The log interval can be manually set to any rate between 1 and 1860 seconds in any combination with the
number of days before a new file is started. To do this, turn off the “Fixed Interval” option and enter in the
desired logging rate in seconds.
NOTE: Logging at shorter intervals allows the MC to capture fast changing processes, but the data files can
become extremely large. Files that exceed the capability of the MC data viewer (>520KB in size) will
have to be extracted from the MC using a USB memory stick or FTP file transfer in order to be viewed
remotely on a PC.
Files larger than the 520KB limit will not be automatically, digitally signed by the MC. If the files are to
be digitally signed, this must be done manually by extracting the files and using the FDC data viewer
program running on a remote PC.
To manually start data logging, press the “Data” button. Any time logging is enabled, the indicator on the Data
button will be illuminated. To stop data logging, press the Data button again. Data logging can also be started
automatically by turning on the “Start” or “Program” option.
The
Start option automatically turns data logging on whenever the MC is first powered on. This action simulates
that of a standard chart recorder.
The
Program option is a convenient method for gathering information that pertains only to the operation of an
automatic ramp/soak program. When selected, the MC will turn the data logger on at the beginning of a program
and off once the program is completed. This eliminates the need to scan through extensive data records to find
the specific information you are looking for from a particular time period.
NOTE: When more than one loop is configured and the program operating mode is set to “Single”, data
logging will start when a program is started on any of the loop controls. If more than one loop is
running a program, all of them must then be stopped before data logging will be stopped.
The
Email icon next to the data log on/off button allows the user to select the currently open data file and email
the file to any user that has been setup to receive emails from the MC.
The
Disk icon next to the Email icon allows the user to save the currently opened data file to a USB memory
device connected to the MC.
8.2.1 Calculating Log File Size
The MC saves the log file in a text based format (.csv), so the amount of memory consumed for each reading
is dependant upon the number of digits required to accurately display the value. This optimizes memory usage
but also makes calculating an exact file size difficult. To obtain a worst case approximation of the resultant file
size, use the following formula:
File Size (KB) = 1 + [0.023 + (0.006 * number of log points)] * number of readings