Instruction manual

ManualsBrandsEmerson ManualsConsumer electronicsSolu Comp Xmt-P-FF/FI

7.6 Setup Cust

The Model 5081-C contains a curve fitting program that can create a second order curve for

3 to 5 user supplied data points. if only two points are entered, a straight line will be used.

These points are from numerical data previously collected that is entered via the keypad. All

data point must be approximately the same reference temperature.

Best results will be obtained by selecting data points that are representative of the typical

operating range and are at least 5% different conductivity values. Plotting the graph of con-

ductivity vs. concentration for the data points of interest before using this procedure is highly

recommended. This will insure that unsuitable points (i.e. two concentrations with the same

conductivity) and critical points (that best describe the curve) can be determined. All data

points should be either on the rising side of the conductivity versus concentration curve or the

falling side, but not both (i.e. both side of the conductivity maximum or minimum). Following

these guideline will simplify the data entry procedure and provide optimum results.

The first point entered "Co nd 1"should be at the normal operating condition. o ther points,

both above and below "Co nd 1" can then be entered. Very nonlinear conductivity curves may

need additional points to characterize these regions. d o not use the same data for more than

one point and only use real data - do not interpolate.

NOTE

The default values for the custom curve are three data points, reference tempera-

ture of 25°C and a linear temperature slope of 2%/°C. This combination will yield

the best results in most applications. if normal operation is over 40°C or under

10°C, the reference temperature should be changed to the normal process tem-

perature. if the temperature slope at the reference temperature is known, it can be

used.

7.6.1 Procedure

MODEL 5081-C SECTION 7.0

PROGRAMMING

1. From the main menu, press PRo G; then press NEXT four times. SetUP CuSt will

appear.

2. Press ENTER. t rEF will appear. if needed, change the reference temperature from

the factory default 25°C (77°F) to a different reference temperature for the process.

Press ENTER.

3. UnIt will appear. Press  or



to select the desired measurement units: µS (micro-

Siemens), nS (milliSiemens), none (no units displayed), % (percent), or ppn (parts per

million); then press ENTER.

4. NUM PtS will appear. Press  or



to select the desired number of data points for a

custom conductivity curve. Selecting 2 will generate a linear relationship for conductiv-

ity and concentration at the given reference temperature.

a. Enter the concentration for Pt. 1 (displayed as µS 1). Press ENTER.

b. Enter the known conductivity for Pt. 1 in µS/cm. Press ENTER.

c. Complete this process for additional known data points. Press ENTER.

5. CALC Cust will appear briefly. Press ENTER. PrOCESSinG will appear briefly; then

APPLy CUSt will appear. Press ENTER to enter the custom curve into memory and

return to the SetUP CuSt screen.

The Custom curve will now be used to display and output all conductivity (or resistivity)

measurements if Cust is selected in the d isplay menu for measurement type.

PRo GRAM

t ref

EXiT NEXT ENTER

PRo GRAM

UnIt

EXiT NEXT ENTER

PRo GRAM

Num Pts

EXiT NEXT ENTER

PRo GRAM

Calc Cust

EXiT NEXT ENTER

t ref 25.0

Units

µ

num pts 3

µ

S 1

Cond 1 0.000

µ

S 2 0.000

Cond 2 0.000

µ

S 3 0.000

Cond 3 0.000

Calc Cond

Apply Cust