PQS 1 PAR Quantum Sensor FOR MEASURING PHOTOSYNTHETICALLY ACTIVE RADIATION Designed for outdoor and indoor use Excellent quantum response Integrated leveling base Introduction Light plays a crucial part in plant and crop growth. Absorption of light (mostly by chlorophyll) drives the photosynthesis process whereby carbon dioxide and water are photo-chemically converted into glucose and oxygen. Light which a plant can use for this process is called Photosynthetically Active Radiation (PAR). The actual response differs depending on the plant or crop. A standardised PAR spectral response in the visible light range between 400nm and 700nm wavelength was defined by McCree (1972) such that each photon within this region is equally absorbed. ‘Blue’ photons of shorter wavelength (higher frequency) have more energy than ‘Red’ photons of longer wavelength. The amount of PAR is commonly expressed as Photosynthetic Photon Flux Density (PPFD) with a unit of µmol/m²·s. Applications In horticulture, to optimise crop timing and quality in greenhouses, In agriculture measurement of PAR helps to predict growth a delicate control of light intensity is necessary. In order to achieve rates and estimate crop yields. this continuous monitoring of the PAR levels of natural sunlight and artificial lighting inside the greenhouse is required. The PQS 1 PAR Quantum Sensor is designed to provide accurate, continuous measurement of PAR outdoors or In forestry applications the amount of PAR is a key research indoors. The rugged construction makes it well protected parameter. It can be measured above, within and below the forest from harsh weather conditions around the world and from canopy to retrieve valuable data on plant physiology and leaf area.

Specifications Spectral range (50 % points) PQS 1 PAR Quantum Sensor is designed for continuous outdoor or indoor installation or for portable field use. The diffuser provides excellent directional (cosine) response and is easy to clean. Expected output range Maximum operational irradiance The mounting flange incorporates a bubble level and adjustment screws for easy leveling. A threaded hole takes the accessory screw-in mounting rod for fitting to masts and poles. The standard cable length is 5 m, with an option of 15 m. Non-stability (change/year) Non-linearity (0 to 10,000 µV/µmol/m²·s) < 1 % Directional...