This Irradiance Sensor is used to measure the radiation flux density of Solar PV Plants having an 4-20mA Input Datalogger. Besides Irradiance, it includes also an Internal cell Temperature Sensor. It is supplied along with Mounting Bracket and Cable.
WORKING PRINCIPLES
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 4-20mA protocol. The electronic circuit is optimized for low power consumption.
CONSTRUCTION FEATURES
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.