Laurel Electronics LTA DPM SERIES ANALOG INPUT - Manual (Page 27)

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18. CUSTOM CURVE LINEARIZATION
Curve.exe is a DOS-based, executable PC program used to set up an Extended transmitter so
that the analog output and internal digital readings have a user-defined, non-linear relationship
with the input signal. For example, it allows a transmitter to correct for transducer nonlinearity
or to transmit the volume of an irregularly shaped tank based on liquid level. The calculated
linearizing parameters are downloaded into non-volatile memory of the transmitter. The curve-
fitting algorithm uses quadratic segments of varying length and curvature, and includes dia-
gnostics to estimate curve fitting errors. The program is self-prompting, avoiding the need for
detailed printed instructions. This manual section is only intended as an introduction.
GETTING STARTED
Download curve.exe from the distribution CD into the same directory that will contain your
data files, such as c:\curves. Connect your transmitter to the PC and double-click on curve.exe,
which is an executable file. Follow the steps on the computer screens, which will prompt you
and provide extensive help information. Pressing R (Enter) returns to the main menu. You will
be given the choice of four data entry modes, all of which are explained in detail.
1) Text file entry mode,
2) 2-coordinate keyboard entry mode,
3) 2-coordinate file entry mode, and
4) Equation entry mode.