Non-linear sensor example

You have a photoresistor-based illuminance sensor that measures light output from 0 to 800 lux, supplying a resistance of 30K ohms to 3K ohms. Using a ResistiveInputPoint, select the conversion type Generic Tabular, and click the edit control for the Tabular Conversion Dialog.

In the dialog, enter the sensor’s non-linear response curve (shown below). Configure this point’s facets to have units: “illuminance,” “lux” (lx), and the same units in the point’s Linear Calibration Ext.

Example illuminance sensor source (ohms) to results (lux)

Ohms

Lux

3000

800

3200

700

3500

600

4000

500

4200

450

4600

400

5000

350

5500

300

6100

250

6900

200

8200

150

10200

100

10900

90

11600

80

12400

70

13300

60

14400

50

15800

40

17700

30

20300

20

30000

0