SMA SUNNY CENTRAL - Manual (Page 44)

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44 SC-BEN092751 User Manual
Example Calculations: Pyranometer
A pyranometer has an output voltage of 0 to 10 V. This corresponds to irradiation of 0 to
1350 W/m².
If M = 5 V:
Example Calculations: Temperature Sensor
A temperature sensor with a converter outputs 4 - 20 mA. This corresponds to a temperature range
of -30 to 80 °C.
If M = 4 mA:
Ml = 0 V Mu = 10 V
Dl = 0 W/m² Du = 1350 W/m²
Formula Calculation
G = (Du - Dl) / (Mu - Ml) G = (1350 - 0) / (10 - 0) = 135
O = Dl - (G * Ml) O = 0 - (135 * 0) = 0 W/m²
Formula Calculation
D = (G * M) + O 135 * 5 + 0 = 675
Ml = 4 mA Mu = 20 mA
Dl = -30 °C Du = 80 °C
Formula Calculation
G = (Du - Dl) / (Mu - Ml) G = (80 - (-30)) / (20 - 4) = 6.875
O = Dl - (G * Ml) O = (-30) - (6.875 * 4) = -57.5 °C
Formula Calculation
D = (G * M) + O 4 * 6.875 + (-57.5) = -30