Cree CXB3590 gets weaker by time?

Hy guys, I have a custom made lamp with 15piece CXB3590 with strong enough active cooling, but i think they do not give as much brightness as they used to. Plants are bushy, but fruits are smaller. The LEDs are about 3 years old now. How could I test if the light is less?
If I need to change the COBs, is there any more efficient than CXB3590?

Without expensive equipment tough one. A simple comparison test with a new 3590 and a cheap digital light meter same current, distance etc. I've been running 16 since 13. I run them at ~37 watts each so I expect them to outlast me.

Lower the lights for higher intensity, consider cleaning them too.

Funny you mention the drop off, someone posted a vid earlier today of migros youtube test showing initial drop off in efficiency after a year.

I wouldn't run out and buy new lights off the back of that though

dandyrandy said:

Without expensive equipment tough one. A simple comparison test with a new 3590 and a cheap digital light meter same current, distance etc. I've been running 16 since 13. I run them at ~37 watts each so I expect them to outlast me.

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Awesome, could you suggest a good enough cheap light meter?

Not really. A phone app would probably do. The key is comparing it to a known new one. Same distance etc.

Damn, with power meter I realized the power consumption is only 240W, while 600W should be for the 15 piece of COBs. So of course my tomatoes did not grow too well. Once i did cut the wire to the china potentiometer, the consumption went back to the normal 600W.

DackEW said:

Damn, with power meter I realized the power consumption is only 240W, while 600W should be for the 15 piece of COBs. So of course my tomatoes did not grow too well. Once i did cut the wire to the china potentiometer, the consumption went back to the normal 600W.

Click to expand...

So why's your question ?

BTW, I got a 15 piece DIY light too!