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Looks awesome Supra. Was wondering why two wires per terminal but that is just the mirror reflection... The photo's don't do justice to the massive scale that it must be.

Plan is looking good overthinker. So yeah I tend to warn about the high voltage drivers. It would be terrible if some kid electrocuted himself because of what he read here. On the other hand if you know what you doing and are always aware that there's 400V going into your growroom it is an...

The PAR you can expect can be calculated. Your room is 0.4m2, you have planned 110W of LED power, and a Vero at half test current (3000K or 4000K) gives about 2 umol/s per Watt. That gives 110*2/0.4 = 550 umol/s/m2 on average. That is an adequate amount but it would be nicer to have double that...

For a cabinet it's easy to use the walls for reflection, no need for reflectors on the Vero. This gives a much better spread of light. Ideally the upper half of the walls with a mirror surface (to diminish the edge effect) and white everywhere else. The 3000K provides just the absolute bare...

Richelsdorfite I am amazed how well it agrees with each other. Looking very good :-P Yes it's the 470nm. It did look too good to be true, and of course it was. The forward voltage should be 3.1 and not 2.9 giving an efficiency of 60.9% (LER is unchanged). I was curious to see how well modern...

I have checked the CIE data that I am using and it turns out it is the wrong set. Instead of CIE 1931 data, I've been using the Sharp-Stockman 2005 data :wall: This picture from Wikipedia shows the differences: The solid black curve is the correct one and I've been using the dotted black...

I have made a spreadsheet using your data and your way of calculating. The LER is still 204.... Perhaps the CIE data is different? You can check everything in the attached spreadsheet.

The formula that I use is LER = 683.0*sum(cie * spectrum) / sum(spectrum) with cie an array with CIE 1931 data and spectrum the array with spectral data; summation is over all wavelengths.

With your XP-E red data I get a LER of 204 compared to 201 with my data. Reasonably close given that it has been reverse engineered from a graph. The LER values (or its reciprocal) must already be somewhere in your speadsheet. For example when computing the efficiency = efficacy/LER.

Hmm that deviates a bit too much for some, like the XPE red. Can you post your LER values? (Luminous Efficacy of Radiation). The LER value is purely is property of the spectrum's shape and the rest follows from it, so it would be easiest to compare the LER values. How do you digitize the...

It's great to see you analyzing all this. Turns out the Hans panel is just as efficient as Cree CXA or Bridgelux Vero COBs that also give about 1.8 umol/s/W. I would like to ask if you could compare the LER values that you have calculated with the one that I have, so as to estimate the margin...

The LEDs are 6V and you put 12V over them...... Thanks to the overload protection of the meanwell driver they are not fried. The protection is also what makes it flicker, it keeps trying until the fault situation is remedied. You can connect the LEDs in series instead of parallel but it's still...

Yes that will make it a lot easier to keep it cool. For me 4000K is the Goldilocks of the Vero family. For CXA it would be 3500K. Both for flowering. I did some simulations with mixing whites and concluded it's simpler to just pick one color temp. Here is one example Abiqua (the new...

These royal blue's are so powerful that you would only have a few of them to spread around, plus the plants will actively grow towards them, so the lights would have to be put higher I think. There is not much point in mixing different whites, so why not choose a single color temp to rule them...

That would work, it's about 500 W/m2, assuming an efficiency of 35% it becomes 175W/m2 of pure light or about 800-900 umol. A low target would be 400 umol and a high target 800 umol so you would be aiming high. So what COBs (brand, size, color temp) and drivers are on the order list?

Did you try a reading with all lenses removed. For your situation with four reflecting walls at close range this could give a better spread and perhaps more light on the plants.

Going from lumens to umols is not so simple, it is explained in the first few pages of this thread. If you have any specific questions let me know. The umols per Watt for the Vero family, at test current and 25C: Emitter umol/s/W Decor 1.4 3000K 1.76 4000K 1.78 5000K 1.83 So the...

This is very good, it means that the output current is not duty cycled and that the dimming really is analog. For a grow light that is exactly what you want, as dimming it will let the light run more efficiently. PWM dimming would not have that efficiency beneifit since the output current is...

Smokey I have a question about dimming with the trimpot. Do you know if this dimming is really analog or if it's PWM?

Here's a nice intro to LED drivers. Consider running the vero 18 in series at 700mA.