Laurel Electronics LAUREATE SERIES 2 DIGITAL PANEL METER - Manual (Page 52)

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21. CUSTOM CURVE LINEARIZATION
Curve.exe is a DOS-based, executable PC program used to set up an Extended meter so that
the readings have a user-defined, non-linear relationship with the input signal. The calculated
linearizing parameters are downloaded into non-volatile memory of the meter. For example, it
allows a meter to correct for transducer nonlinearity or to display volume of an irregularly
shaped tank based on liquid level. The curve-
fitting algorithm uses quadratic segments of
varying length and curvature, and provides
diagnostics to estimate curve fitting errors.
The program is self-prompting, avoiding the
need for a detailed printed manual. This
manual section is only intended as an intro-
duction and get-started guide.
PREREQUISITES
1) PC-compatible computer with an available RS232 or USB port.
2) Extended meter.
3) An RS232 or USB board in the meter. This board
can be removed following meter setup.
4) An RJ11-to-DB9 RS232 cable or a USB cable
to connect the meter to the PC (see Section 1,
Ordering Guide).
5) Curve.exe software (downloadable from the web
at no charge).
GETTING STARTED
Download curve.exe into the same directory that will contain your data files, such as
c:\curves. Set the meter baud rate to 9600. To do so, press the
key to get to SEr 1 , then
set the entry to __050 . Set the meter address to 1. To do so, press the key to get to SEr
2 , then set the entry to _0011 . To execute the program from Windows, simply double-click
on curve.exe, which is an executable file. Follow the steps on computer screens, which will
prompt you and provide extensive information. Pressing R (Enter) returns to the main menu.
You will be given the choice to enter your data in one of four modes:
1) Text file entry mode, with an X value in one column and a Y value in another. There
can be additional columns, which are ignored. The file must have a DOS name of up to
8 characters and the extension .RAW. There can be from 5 to 180 rows. X is the input
value and should be in the unit of measure for which the meter was set up, such as mV,
V, mA or A. Y is the desired corresponding reading and can range from -99999 to
99999 with any decimal point.
2) 2-coordinate keyboard entry mode, where an actual X input signal is applied, and the
desired Y reading is entered from the keyboard.
3) 2-coordinate file entry mode, where an actual X input signal is applied, and the
desired Y reading is provided from a file.