How is my DIY light build?

[idf420]

Hello growers

I decided to build my own lights.. just because I love building things my self.
so I decide to go with CXM22 GEN4 3500k cob with a HLG-80-48H driver.
the light draws about 70-75W from the wall.

now, my question is it enough for one plant in a really small closet? (L: 65cm W: 44cm H: 180cm), and which Hight is optimal for seedlings?

really appreciate the help guys and if i posted it in the wrong place please excuse me

 

[bluter]

would go constant current not constant voltage on the driver. driver is also large enough to cause a runaway and possible fire in the current config.

go check out led gardener dot com for excellent info on cob and strip lighting. there is an onsite calculator to match your emitters to the proper drivers.

 

[idf420]

i am using a constant current driver. and what do you mean by "cause runaway"?

i did checked led gardener, the calculator didn't have a configuration for 1 cob ..

 

[bluter]

the driver you listed is a constant voltage driver not a constant current driver. it also doesn't match so well. can be done, but is a different build approach and would recommend using multiple cobs in that type of build.

a runaway is when an emitter fails, piling it's voltage on to the next emitter, which then fails, etc. etc. can lead to a fire situation. cobs fail when over driven. that driver is a bit big for one cob.

i built and sold cob rigs for a few years.

personal veg rig

clearance

• bluter
• Apr 7, 2018

personal flower rig

12 cob citizen rig.JPG

• bluter
• Sep 19, 2019

600 watt real draw 12 cob citizen clu048 1212 light rig

consider constant current drivers. the build is much easier.
also you might want to look in to doing a strip light. may work better for that size space.

 

[idf420]

i put the wrong ID on the driver, i am using a HLG-80H-48A.

when i looked at the datasheet it said that its CC and CV.

so i can lower my wattage consumption... i am just afraid that it wont have enough juice for my grow space.. or am i wrong here? hah would really appreciate the help.

 

[bluter]

what the forward voltage on that chip ?

if you go 1400ma current the driver jumps to an hlg 1XXH-54A. should be 3 or 4 that match. the current changes, driver is actually a bit bigger.

 

[idf420]

the vf is 48-53V..

i am running the cob at 1500ma and 50v, thats 75W.
the datasheet of the cob show that it can be used on 198W.. so i use less than 50%..am i missing something?
also at this wattage and grow space.. can i even grow something?

 

[idf420]

the datasheet of the chip:

https://download.luminus.com/datasheets/Luminus_CXM-22_GEN4_Datasheet.pdf

 

[bluter]

when i looked at the datasheet it said that its CC and CV.

one is always allowed to float. the driver you are leaning to is constant voltage. you have to choose one or the other when you build. will effect 100% of how you build it.

it's the 48A in your driver spec denoting constant voltage. a constant current driver spec ends in milliamps 700a, 1050a, 1400a, etc. 700a and 1400a is pretty standard for cob rigs.

you might be forced in to constant voltage. not sure there is a constant current driver that matches a single cob.

 

[bluter]

running two cobs would be a better build over all and probably easier. what you really need is a matched driver for that one cob - they don't really make it. the assumption is you are always running multiples. the driver you chose is probably the closest. everything i look at is at 50A or over.

2 cobs and a dimmer is the easy way out. i would also look at strip builds. might be more bang for dollar in that size space.

 

[bluter]

also i run b spec hlg drivers which are the ones with external dimming. there are a couple different ones. you can run an a spec, but the dimming is adjusted with a set screw. either are acceptable, but the b drivers are much more useful.

you might find an elg driver. they are just as good at half or less of the cost. most commercial led runs elg now.

 

[idf420]

Awesome.. i saw some strips that looked perfect for my space but they are only 62w..(1300ma and 48v )
Will my driver work with those bars or maybe a 2 bars configuration running at 35w will be better?

 

[bluter]

are you stuck with that driver ?

if you are just run as many bars as you can stuff on to it. the specs change with the chipset , length of the bars etc. you can get the latest gen LMs pretty cheap in different lengths.

will take a bunch of math. try that info i sent. there are step by step walk throughs on both cob and strip builds, and the math to get you there.

they also delve in to different ways to wire it up and the differences between constant voltage and constant current builds.

 

[VetSmoke85]

Hey @idf420 I'm currently doing the same for a stealth flower tent I've built. It's an old 60x30x90 canvas shoe rack I've modified. I ummm'd and ahhh'd between a COB or a strip build for a while and went with strips. Just placed the order. My plan is to have 8 of the Bridgelux EB Gen 2 280mm strips (cheap as chips), wired in series with an ELG-150-C700A driver (dimmable 350-700mA, output V 107-214). Plan to run them at the nominal current of 350mA. Below are some calculations with current, forward voltage and power. The driver will do 10 strips so I can add a couple if needed later on. As I'll be running them pretty soft I don't plan to use a heatsink. Just mount the strips onto an aluminium frame. All in it's cost me £76.

Can't wait to get it built now. Looks like @bluter is the right man to help guide you. I'm hoping I haven't made any errors in my calculations and component selections but pretty sure it will work nicely for my space. Likely only have a canopy of 30x45 so even run at 350mA it should be enough.

 

[Nunyabiz]

This is pretty much my build right here except that I split mine up into two separate 325w lights with 8 strips each for 650w total, both on dimmers instead of just one big light so that it would fit my space.
Only time I run it full blast is late flower.

 

[idf420]

are you stuck with that driver ?

if you are just run as many bars as you can stuff on to it. the specs change with the chipset , length of the bars etc. you can get the latest gen LMs pretty cheap in different lengths.

will take a bunch of math. try that info i sent. there are step by step walk throughs on both cob and strip builds, and the math to get you there.

they also delve in to different ways to wire it up and the differences between constant voltage and constant current builds.

Well.. i can always sell it but would rather work around with what i already have.
i looked at the datasheets again and by the looks on it if i stay in the 28-48V region i will get CC of 1.7A.. am i right?

 

[idf420]

Hey @idf420 I'm currently doing the same for a stealth flower tent I've built. It's an old 60x30x90 canvas shoe rack I've modified. I ummm'd and ahhh'd between a COB or a strip build for a while and went with strips. Just placed the order. My plan is to have 8 of the Bridgelux EB Gen 2 280mm strips (cheap as chips), wired in series with an ELG-150-C700A driver (dimmable 350-700mA, output V 107-214). Plan to run them at the nominal current of 350mA. Below are some calculations with current, forward voltage and power. The driver will do 10 strips so I can add a couple if needed later on. As I'll be running them pretty soft I don't plan to use a heatsink. Just mount the strips onto an aluminium frame. All in it's cost me £76.

Can't wait to get it built now. Looks like @bluter is the right man to help guide you. I'm hoping I haven't made any errors in my calculations and component selections but pretty sure it will work nicely for my space. Likely only have a canopy of 30x45 so even run at 350mA it should be enough.

Thanks for the help dude!! will defiantly check them out!

 

[bluter]

Well.. i can always sell it but would rather work around with what i already have.
i looked at the datasheets again and by the looks on it if i stay in the 28-48V region i will get CC of 1.7A.. am i right?

the current will float. you have a constant voltage driver.

edit: it's gonna depend on the number of cobs you run. you have to run enough that it pulls the full amperage from the driver, without having too many, which results in nothing happening. at that point, and that point only, will it kick in to constant current, you have to have everything matched. this is different to a constant current build.

i'd start with learning the definitions of amperage, voltage, current, and watts. they are all different, they all come in to play, understanding them will clear up what you are trying to figure out.

would also recommend a strip light if you can get strips that will match up nice. in most builds you would start with what you want for emitters, which would dictate the power requirements, which would determine the driver. it's harder doing it in reverse.

i didn't run the math on the cob you were looking at. i'll have a peak tonight to make sure. i don't think that driver will fire that cob.

 

[bluter]

i am corrected. it looks like it does, just. will look at it closer tonight.

 

[VetSmoke85]

Just in the process of building mine now. Will share with you once I'm done. @bluter I wonder if you can confirm something for me? There is no PEC wire on the driver input and nowhere to attach one. On the label it says case grounded. I'm guessing this means it is Class II and doesn't require a PEC to be connected?