Reversed Polarity Protected Pyranometer provides 0 to 1 Volt or 4 to 20 mA analogue output. The Pyranometer operates on a power supply rate of 5 VDC to 30 VDC. The Pyranometer is protected against over voltage, reversed polarity and short circuiting. Reversed Polarity Protected Pyranometer measures global solar radiation on a horizontal plane and when tilted with the same angle as a PV panel it measures the tilted global radiation, for PV module efficiency calculations.