Help regarding choosing solution for adding UVA/UVB LED's to a DIY COB LED grow light.

Hello.

I've built a DIY COB LED grow light using two CXM-32-35-80-54-AC00-F2-3 and the driver I am using(HLG-320H-C2800A) is allowing me to adjust the constant current output between roughly 1400mA ~ 2800mA which estimated from the datasheet of the CXM-32 would for 2 connected in series result in roughly 170W - 300W(I use them at 170W which seems as too much for my tent of 2*2*5.5 foot and I am looking into ways of modifying the driver so to allow me to dim the LED's more, using a external switch and PWM introduces some problems which I haven't been able to grasp yet in order to determine if it can be done).

In any case assume a combined output of 170W for those two CXM-32*s in series.

I have come to want to add both UVA and UVB to my grow light but after having gone through all the datasheets I am unable to figure out how hard to drive the UV LEDs which are all on starboards, I don't even know if the UVB LED is sufficient if I only use 1 LED which is all I can afford.

I know that this is a sort of controversial subject and there are probably differences of opinion about how much of UVA and UVB is sufficient but I thought that nature would be the reference but right now I can't recall how much of UVA/UVB there is on the earths surface on average.
In any case I wouldn't mind any advice about this too(the amounts), I have begun reading through the very long thread about UVA/UVB here on the forum but as someone with ADD I will probably not manage to finish reading it. Maybe I should use those reptile lights often used for added UV as a reference...

I have selected boards which feature these which are pretty much my only options and I am to select one for UVA and one for UVB, the LED's are these:
UVA: one of the four different LST1-01G0 LED's.
UVB: ether MTSM310UV-F1120 or MTSM295UV-F1120.
Again, these are meant to be used with two CXM-32 connected in series.

There are simply too much I don't know about the subject of lighting and then energy that is output from these, and how different values can be related to each other, just to say it I have ordered a quite cheap lux-meter to be able to estimate the PAR or other parameters since the datasheet only features Lux.

Is it necessary for me to measure the output of my grow light before any choices may be made regarding these UV LED's and at which level to drive them?

As for the distance between the grow light and the plant, right now it's about 2 feet but I think that later in the flowering(6 days since I switched to 12-12 on a 95% sativa while ScrOG'ing) it might get closer since I can't raise the grow light more than another 2 feet(I don't have the experience to anticipate how much the plant will stretch).

Any advice would be greatly appreciated, but I really don't know what I am asking for in terms of effort required from any helper.

I could have written up some numbers from the datasheets but since I really don't know what values could be used to determine this I think it's better to just link to the datasheets.
No seems as I still am not allowed to use URL's in my posts, that makes this hole thing a lot more demanding I think since I had neatly linked in the relevant datasheets everywhere in the post.

I hope you all will have a nice day, cheers.
 

Moflow

Well-Known Member
Hello.

I've built a DIY COB LED grow light using two CXM-32-35-80-54-AC00-F2-3 and the driver I am using(HLG-320H-C2800A) is allowing me to adjust the constant current output between roughly 1400mA ~ 2800mA which estimated from the datasheet of the CXM-32 would for 2 connected in series result in roughly 170W - 300W(I use them at 170W which seems as too much for my tent of 2*2*5.5 foot and I am looking into ways of modifying the driver so to allow me to dim the LED's more, using a external switch and PWM introduces some problems which I haven't been able to grasp yet in order to determine if it can be done).

In any case assume a combined output of 170W for those two CXM-32*s in series.

I have come to want to add both UVA and UVB to my grow light but after having gone through all the datasheets I am unable to figure out how hard to drive the UV LEDs which are all on starboards, I don't even know if the UVB LED is sufficient if I only use 1 LED which is all I can afford.

I know that this is a sort of controversial subject and there are probably differences of opinion about how much of UVA and UVB is sufficient but I thought that nature would be the reference but right now I can't recall how much of UVA/UVB there is on the earths surface on average.
In any case I wouldn't mind any advice about this too(the amounts), I have begun reading through the very long thread about UVA/UVB here on the forum but as someone with ADD I will probably not manage to finish reading it. Maybe I should use those reptile lights often used for added UV as a reference...

I have selected boards which feature these which are pretty much my only options and I am to select one for UVA and one for UVB, the LED's are these:
UVA: one of the four different LST1-01G0 LED's.
UVB: ether MTSM310UV-F1120 or MTSM295UV-F1120.
Again, these are meant to be used with two CXM-32 connected in series.

There are simply too much I don't know about the subject of lighting and then energy that is output from these, and how different values can be related to each other, just to say it I have ordered a quite cheap lux-meter to be able to estimate the PAR or other parameters since the datasheet only features Lux.

Is it necessary for me to measure the output of my grow light before any choices may be made regarding these UV LED's and at which level to drive them?

As for the distance between the grow light and the plant, right now it's about 2 feet but I think that later in the flowering(6 days since I switched to 12-12 on a 95% sativa while ScrOG'ing) it might get closer since I can't raise the grow light more than another 2 feet(I don't have the experience to anticipate how much the plant will stretch).

Any advice would be greatly appreciated, but I really don't know what I am asking for in terms of effort required from any helper.

I could have written up some numbers from the datasheets but since I really don't know what values could be used to determine this I think it's better to just link to the datasheets.
No seems as I still am not allowed to use URL's in my posts, that makes this hole thing a lot more demanding I think since I had neatly linked in the relevant datasheets everywhere in the post.

I hope you all will have a nice day, cheers.
I'd like a link to the uva uvb leds.
 

InTheValley

Well-Known Member
Hey man, I cant answer anything, but cant wait to see a harvest with these Cobs. I love my CXM22's, im getting beer can colas with just 250 watts. (4pc)

I have gotten buds as close as 6 inches with no harm, as long as a fan is blowing direct heat from the COBS, distance doesnt seem to be an issue. I will have my PAR meter tomorrow to get a better understanding of the power.
Keep us posted
 

Rocket Soul

Well-Known Member
@Planet Tomato Basic advice for adding UV is to keep them on a separate driver and separate timer. That way you can control better how much uv they get. Start with a little around midday. Add some more. UV will make buds mature faster, even over mature in some cases. You might have to do a staggered harvest.

You may also find that your main light fixture and UV light needs to be at separate heights.
I would ask @Randomblame , he uses uv-tubes with success
 
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