A silicon solar cell can be used as an irradiance sensor, because the short-circuit current is proportional to irradiance. Our sensors are built out of a monocrystalline solar cell connected to a shunt. Due to the low resistance of the shunt the cell operates next to short circuit.

The temperature coefficient of the short-circuit current creates a small error. The compensation is realized by using a temperature sensor laminated to the rear side of the solar cell. The measuring signals of short- circuit current of the cell and the resistance value of the temperature sensor are measured by a micro controller. The calculated values of irradiance and temperature given onto a 0-1,5V protocol. The electronic circuit is optimized for low power consumption.


Monocrystalline Cell: The cell is laminated with 2 EVA sheets, one Tedlar sheet and 3mm tempered glass under 180 °C homogeneous temperature and under vacuum effect. The size of the monocrystalline cell is 52×52 mm² or 31x31mm².

Sensor Box: It is an UV protected aluminum box. The sensor box has two opening access and the mounting holes on its sides are for easy site installation. There are three options for IP Class; IP54, IP65 and IP68. For ventilation purpose, there are 1mm holes at bottom side of the box, or a ventilation plug on its side.

Item Code 3S-IS-T-V
Reference Cell Monocrystalline Silicon (31 mm x 31 mm)
Current Shunt High precision shunt resistor directly soldered to the terminals of the cell
Irradiance Range 0 – 1500 W/m²
Uncertainty ≤2%; as per IEC61724-1 standard Class A
Resolution 0.1 W/m² ≤ 1W/m²; as per IEC61724-1 standard Class A
Response Time 1 sec. less than 3 sec; as per IEC61724-1 standard Class A
Drift Very small drift of <0.3%/ year
Field of View Larger than 160° as per IEC61724-1 standard Class A
Tilt-Azimuthal Angle 0°- 0° , ≤ 1°; as per IEC61724-1 standard Class A
Output Rate 1/s
Data Output Analog 0-1,5 V
Power Supply 12 to 30 V DC
Power Consumption 15 mA max @24 VDC
Electrical Connection 3 m LIYYC11Y PUR Cable, UV and Weather Resistant
Cell Temperature Sensor Type PT1000 Class A as per EN 60751
Operating Temperature Range -40°C to +85°C
Operating Humidity Range 0 to 100 %
Box Dimensions 142 mm x 110 mm x 40mm (WxLxH)
Weight 0.3 kg
IP Rating IP54 (IP65, IP68 options)
Sensor Housing Material Aluminum
Compliant Standard IEC 61724-1:2021 and IEC 60904
Calibration Each sensor is calibrated under Class AAA Sun Simulator as per IEC 60904-2 and IEC 60904-4 by using a reference cell calibrated by ISFH-Germany
Test The test is carried under natural sunlight by using a calibrated reference cell from Fraunhofer ISE, Germany