Example 23: corr_irr - irradiance

This equation computes first a temperature corrected irradiance value in Volts:

\[Irr_{tempcompensated} = x_2 \cdot (x_0 + x_1 \cdot R) + (x_3 + x_4 \cdot T_{sensor} + x_5 \cdot T_{sensor}^2)\]

Then applies a linear equation to convert to final units:

\[Irr_{calibrated} = c_0 + c_1 \cdot Irr_{tempcompensated}\]

where

  • c0, c1 are calibration coefficients.

  • x0, x1, x2 are coefficients required to convert the raw data in Volts.

  • x3, x4, x5 are the temperature correction coefficients.

  • n0 is the index of the temperature of the sensor channel.

  • Tsensor is the temperature of the sensor in °C.

  • Irrtempcompensated is the measured irradiance in Volts and compensated in temperature.

  • Irrcalibrated is the measured irradiance in final calibration units.

Examples

>> channel 3 type
<< channel 3 type = irr_01

Confirm the channel type.

>> calibration 3 datetime = 20171201000000, c0 = 0.000, c1 = 1.0000

Set the core coefficients.

>> calibration 3 datetime = 20171201000000, x0 = 9.983, x1 = 0.2003, x2 = 1.000, x3 = 0.0721, x4 = 0.1049, x5 = 21.29

Set the cross-channel correction coefficients.

>> calibration 3
<< calibration 3 type = irr_01, datetime = 20171201000000, c0 = 0.0000, c1 = 1.0000, x0 = 9.983, x1 = 0.2003, x2 = 1.000, x3 = 0.0721, x4 = 0.1049, x5 = 21.29, n0 = 7

Request confirmation of all calibration coefficients.