Using CitectSCADA > Logging and Trending Data > Using Trend History Files > Floating point
Floating point

Each data sample requires eight bytes of storage. This alters the equation to:

Bytes necessary for each trend = 704 x No. Files + 160 + File Period (secs) x (No. Files) x 8
Sample Period (secs)

The number of bytes necessary then becomes:

Bytes necessary = 704 x 5 + 160 + (7 x 24 x 60 x 60) x 5 x 8
Bytes necessary = 2,422,976 bytes

Note: The calculations above do not take into account the space necessary to store the history file for each trend. This is because these files remain at a set size and therefore do not significantly impact the amount of disk space necessary.

Note: For efficient trends storage, use Windows file compression. By using this method you often can reduce your files to 10% of their original size; the actual amount of compression varies depending on the rate of change of the data.

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