Lux meter usage steps and illuminance calibration method
① Turn on the power.
② Open the cover of the photodetector and place the photodetector horizontally in the measurement position.
③ Select the appropriate measurement gear. If only "1" is displayed on the left end of the screen, it indicates excessive illumination and requires pressing the range key (⑧ key) to adjust the measurement factor.
④ The illuminance meter starts working and displays the illuminance value on the display screen.
⑤ The data displayed on the screen is constantly changing. When the displayed data is relatively stable, press the HOLD key to lock the data.
⑥ Read and record the observed values displayed in the reader. The observed value is equal to the product of the displayed number and the range value in the reader.
For example, if 500 is displayed on the screen and the status is "× 2000" in the lower right corner, the measured illuminance value is 1000000lx, which is (500 × 2000).
⑦ Press the lock switch again to cancel the read value lock function.
⑧ During each observation, take three consecutive readings and record them.
⑨ After each measurement is completed, press the power button to cut off the power.
⑩ Cover the photodetector lid and put it back in the box.
Illumination calibration
Calibration principle:
Illuminate the photovoltaic cell vertically with Ls → E=I/r2, and change r to obtain the photocurrent values under different illuminance. Convert the current scale to the illuminance scale based on the correspondence between E and i.
Calibration method:
Using a light intensity standard lamp, at an approximate working distance of a point light source, change the distance l between the photovoltaic cell and the standard lamp, record the readings of the ammeter at each distance, and calculate the illuminance E using the inverse distance square law E=I/r2. From this, a series of different illuminance photocurrent values i can be obtained, and the variation curve of photocurrent i and illuminance E can be made, which is the calibration curve of the illuminance meter. The calibration curve of the illuminance meter can be divided by the dial of the illuminance meter, which is the calibration curve of the illuminance meter
