Laurel Electronics LAUREATE SERIES 2 COUNTER-TIMER-SERIAL INPUT METER User Manual

Page 70

19. 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.
For example, it allows a meter to correct for
non-linearity of transducers, or to display
volume from pressure at the bottom of an
irregularly shaped tank. The linearizing para-
meters are downloaded into non-volatile
memory of the meter. The curve fitting algo-
rithm is 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 manual.

PREREQUISITES

1) PC-compatible computer with an available RS232 or USB port.

2) Extended meter*.

3) A serial communication board in the meter. This

board can be removed following meter setup.

4) A suitable cable to connect the meter to a PC.

5) Curve.exe software (downloadable 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 to custom curve linearization. To do so, press the

key to get to

ConFG

, then set the fifth digit to

. This digit will only be displayed with an Extended meter*.

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. No software installation is required.

OPERATING MODES

The program will prompt you to enter your data in one of four modes. Pressing R (Enter) at
any time returns you to the main menu.

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.