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4) Equation entry mode, where the coefficients of a polynomial Y = K1X^P1 + K2X^P2 +
K3*X^P3 + … are entered. Up to 20 terms are allowed. An offset can be built into X.
You will be asked if your DPM has a revision of DPM4L or later. You will normally select 2
(yes), since revision DPM4L started to ship in August 2000.
You will be asked to supply the following:
LOW X-COORDINATE VALUE >
LOW INPUT MEASUREMENT VALUE >
HIGH X-COORDINATE VALUE >
HIGH INPUT MEASUREMENT VALUE >
This informs the computer of your signal conditioner jumper settings. Enter 0 and 0 for
the two LOW values. For HIGH X, enter your signal conditioner jumper range in the
same units of measure that you will be using in your *.RAW data input file. Enter 20 for
20 mV or 50mV. For HIGH INPUT MEASUREMENT VALUE, enter 20000
Position of the decimal point from 6=X.XXXXX, 5= XX.XXX, 4=XXX.XXX, 3=XXXX.XX,
2=XXXXX.X, 1=XXXXXX (for DPMs, the leading X is a blank). Specify the same position
that you specified in the dEc.Pt decimal point menu selection.
Follow the steps on the screens to finish generating the custom curve. When prompted to
download the file to the meter, select Y. When prompted to set the meter to custom curve
mode, also select Y.
KEYPAD CONTROL
You can take a meter in and out of custom curve linearization using the meter keypad.
From the Menu mode, press the key to get to ConFG, then set the fifth digit to either 0
(normal linear operation) or to 1 (custom curve operation). This fifth digit will only be
displayed with an Extended meter.
FILES USED OR CREATED BY CURVE.EXE
1) *.RAW is the raw input file generated by all four data entry methods.
2) *.DVD adds three columns from which the smoothness of the input data and obvious
input errors can be judged. The more data points and the smoother the data, the better
the curve fit.
3) *.NUM lists Y readings prior to custom curve linearization and addition of the decimal
point.
4) *.CCF is an internal file used by the software.
5) *.SIM lists simulated linearized meter readings and calculated corresponding errors.
6) *.PRM contains the final hex data that is downloaded into the meter.