What is the luminous efficacy of PT8

Описание: This PT8T grow light has been working 24 hours a day for more than a year.
The ambient temperature here is 33 degrees Celsius, which is quite high,
Today we're gonna take it down and test it?
Let's see how much light is left in this grow light that's been lit continuously for a year.
Photosynthetic photon flux and light efficiency were measured by integrating spheres,
2.6umol/J decreased by 2.7%, PPFD test height 0.2m, PPFD 271µmol/m²/s
Basically, it is the same as before. The actual measurement results were close to the estimates
We'll put it back in place, Continue the burn-in test, test it next year, and report back.
I am a grow light engineer, welcome to discuss plant grow lights.