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Tools to design LED grow lights.

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pisoiu:
Hi all,
Currently I am experimenting with some LED grow lights because I want to create a solution for vertical farms in the future, if it will make economical sense. But in the process of designing LED panels, I lack some knowledge, therefore I ask for some help, if possible.
The panels I designed uses low power LEDs to make things easier with thermal management. For now I have 5 panels to test with, they have blue, red, lime and infrared LEDs, the LEDs are dedicated for horticultural applications. Each panel have near 1000 leds. The power supply is also designed by me because I want to be able to change the intensity for each wavelength independently.
There are 2 main issues in this project which needs to be solved. One is the panel itself, to test it, make it work under all working conditions, to ensure quantity and quality of output light. The other one is using this panel, to make tests on various crops, I already have a hydroponic setup for this.
In order to be able to correctly measure the output from the panels, I use a PAR meter from Apogee Instruments, SQ626, it works on extended range, from 340 to 1040nm. But this gives me only quantitative indication, so for quality of light I will have to purchase a spectroradiometer. Those coming from big names in industry are too expensive for me, but I can afford a model I found on aliexpress, is around $1100.
https://www.aliexpress.com/item/10000015842704.html?spm=a2g0o.cart.0.0.6f173c00FIg70G&mp=1
Unfortunately I know nothing about this brand and there are not many customers of this tool sharing their experiences on the web.
Finally, my problems: in order to change the light output for my leds I use a TPS92513 driver. Output is controlled with a PWM signal of approx. 200Hz. I am not familiar with exactly how a PAR meter or a spectroradiometer are internally built (especially on the ADC section) and I do not know if, for a proper measurement, they require constant light over the sensor and if the measurements are not tricked by PWM modulation. I asked Apogee instruments about that, no answer so far and I also asked chinese manufacturer, but of course they sent me a reply which indicated they did not understand a bit from what I asked. I would like, of course, to avoid spending 1k$ on a tool which is not able to measure correctly PWM modulated light.

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