This Irradiance Sensor Model’s designation is 3S-4IS. It is specially developed to calculate the Performance Ratio (PR) for the PV plants with three or four orientations, as it calculates the average irradiance value as per the number of panels in each direction. The user will be able to set the number of panels in each orientation for the correct calculations. The special design of the electronic box used allows simultaneous connection of up to four Irradiance Sensors, up to four Module Temperature Sensors, an Ambient Temperature Sensor, a Wind Speed Sensor, and a Wind Direction Sensor. The number of panels in different directions, to which the sensors are connected, is entered into the electronic box via 3S-4IS Configuration Tool. The total effective irradiance and total effective module temperature can be calculated and communicated to the datalogger via Modbus RTU protocol. By using these values, the accurate Performance Ratio can be calculated in the monitoring systems.