I was made aware that my HF PAR meter was reading an average of 25% higher compared to the Apogee meter. So, I have been testing my PAR Meter for the last week. I have been using the Sun Calculator on Apogee's website. QUANTUM SENSOR: Clear Sky Calculator, Apogee Instruments Inc.
Several reading every day, and always higher. I have not found a way to recalibrate the meter online. I even emailed Hydrofarm, but have not gotten a response.
So I took things into my own hands. First I took the main unit apart to see if there might be an adjustment, but I did not find a thing. Next was the sensor, took it apart, looked, wiggled and put it back together. Wholly Cow! Now it's reading really high, through the roof high! Took the sensor apart again and took a closer look. The lens was slightly out of it's place, then I noticed the sensor itself being way out of it's place! I went ahead and pushed it down to seat it inside the plastic holder. After putting it all back together, outside I go to test the meter. Damn, it was reading withing .3 Umol compared to the calculator. FIXED! I will continue to test this week.
Lesson: If you drop the meter, chances are that the sensor dislodges from the housing and the readings will be way off after that!
TTKlaus
Several reading every day, and always higher. I have not found a way to recalibrate the meter online. I even emailed Hydrofarm, but have not gotten a response.
So I took things into my own hands. First I took the main unit apart to see if there might be an adjustment, but I did not find a thing. Next was the sensor, took it apart, looked, wiggled and put it back together. Wholly Cow! Now it's reading really high, through the roof high! Took the sensor apart again and took a closer look. The lens was slightly out of it's place, then I noticed the sensor itself being way out of it's place! I went ahead and pushed it down to seat it inside the plastic holder. After putting it all back together, outside I go to test the meter. Damn, it was reading withing .3 Umol compared to the calculator. FIXED! I will continue to test this week.
Lesson: If you drop the meter, chances are that the sensor dislodges from the housing and the readings will be way off after that!
TTKlaus
