The Sun System® PAR Meter with remote sensor measures photosynthetically active radiation (PAR). This product measures the intensity of light, the amount of electromagnetic radiation below a single source, or multiple sources of light.
Features & Benefits:
Measures photosynthetic active radiation (PAR)
Can be used with grow lights or outside with natural sunlight
Simple and easy to use
Compact size with integrated sensor
Line quantum sensors are often used to quantify the variable light in greenhouses and below plant canopies because they provide a spatial average
Sun System PAR par meters are calibrated for both electric light and sunlight. The difference in calibration is close to 10%. A sensor calibrated for fluorescent lamps will read about 10% low in sunlight. A sensor calibrated for sunlight will read about 10% high under fluorescent lamps. The spectral errors are less than 2% for other common electric light sources.
To accurately measure light with a PAR meter, it is important that:
the sensor is level
the sensor head is clean
there are no reflective objects near the sensor
you are not physically interfering with the light source
User Manual can be found HERE
Cleaning the meter is important as debris on the meter is a common cause of low readings. Salt deposits can accumulate on a sensor from evaporation of sprinkler irrigation water and dust, which can accumulate during periods of low rainfall. Salt deposits should be dissolved and removed with vinegar and a soft cloth or q-tip. Dust and other organic deposits are best removed with water, rubbing alcohol or window cleaner. Never use an abrasive cleaner on the lens