My latest creation

I've had an idea in mind for a while and had to build it. I wanted a PPFD of just over 800 in a lamp made to provide coverage for a 2x4 tent and this is what I came up with.



Everything is over powered and underdriven. 2 HLG-185H-C1400s powering 6 Vero 29 3500K at 1.4amps, Two 120mm fans each with their own 12w power supply. Both fans are pushing through the same channel so if a fan or fan supply goes bad the lamp keeps running without much change in CFM.

Veg mode switch flips between 1.4 amps and .560 amps.

EMI power inlet and power outlet.

I was curious how the cooling situation would affect the cobs, hoping the temp readings would be similar from one side to the other. With ambient temp at 30C the first cob in the channel has a Tj reading of 39. The last cob in the channel reads 44. More of a rise than I was hoping for, but well under typical even in a hot room.

All aluminum construction and fairly light considering it has a 36" piece of the 4.6 profile heat sink in there.

Material cost plus shipping was about $500.

I have no use for this light as I'm full up at the moment. I will likely end up ebaying it. But not before I show it off and do some more testing. Seriously considering ordering a par meter.

cool unit, how much do you think you can get for it on ebay ?

where does the air exit ?

Air enters through one fan and out the other.

I'm not sure how much I can get for it on ebay. The metal fabrication is somewhat labor intensive. The cutting and bending isn't bad but then there are about 150 holes to drill. I'd like to make $250 off of it, so adding in Ebay's take probably just over $800 and see what happens.

yeah that's a lot of holes, good luck on ebay!

Mind if I ask where you got your aluminum sheets? I've been sketching up a similar build in 3D what feels like forever so its great to see a final similar product.

Sevren said:

Mind if I ask where you got your aluminum sheets? I've been sketching up a similar build in 3D what feels like forever so its great to see a final similar product.

Click to expand...

You can inquire with HVAC companies, roofing companies, metal fabrication shops. If you have more than one local option ask several of them and weed out the price gougers. If necessary they may be willing to cut it into usable pieces for a fee.

Samonetin, I failed to mention but the drivers are B series. I was originally going to use a potentiometer but changed my mind. I think some people would find it adds value but for myself I'd rather just have a switch to flip. I ordered a couple different resistors. I will have a tent free in a couple weeks and am wanting to get it in there before I sell it and do some testing. If the veg is too weak at .56 amps I can try a different resistor til I have something I'm happy with.

Nice build!
I would really like to see more pics from the building process!
I'm sure it will grow some nice 'n fat nugs.
What do you think of another air intake hole in the middle and both exterior fans for blowing out? This should give more identical cob temps.

I love this man, it looks simply fantastic!. There is a massive difference in labor between making something that is functional vs something that looks professional. I commend you sir.

Randomblame said:

Nice build!
I would really like to see more pics from the building process!
I'm sure it will grow some nice 'n fat nugs.
What do you think of another air intake hole in the middle and both exterior fans for blowing out? This should give more identical cob temps.

Click to expand...

Thanks. I considered something similar to what you suggest from the beginning. Thing is, any of those options negate the inline fan strategy. The only way to find out how inline would work was attempt it... so now I have some data to consider. Once I get the lamp in a proper temp room I expect the max cob temp will be just under 40... and if there is any difference after the break in period with the Arctic Silver 5 perhaps I can hit 36-37 with the hottest cob. Only time will tell.

Obviously though, splitting the fans up would result in cooler temps. I think by using a different strategy I could get maybe get 4-500 more lumens out of it. Whether that is worth ditching the inline strategy is the question I'm mulling over.

Growmau5 said:

I love this man, it looks simply fantastic!. There is a massive difference in labor between making something that is functional vs something that looks professional. I commend you sir.

Click to expand...

Thank you. Hard to tell from the pics but the lamp is first try prototype and does have a few visual flaws. That's why it will be ebayed rather than me rushing to set up an online shop, though I do hope to do limited runs with a minor web presence eventually. Your words are much appreciated

...only my pov... for the inline fan strategy...

...fans are not alineated on the best way from heatsink fins...

...its the same way with conductor for air tubing... better go on inline or right sistems... bad if you go on curves (you add big losses to the system with curves)...your sistem for my eye its a U...conducting the air...better go on I... for better conducting the airflow... both fans working on the same direction of flow air... one push air on inside other sucks the air on inside and push out...

pd1...thanks Guod for the right words... push / pull configuration for fans...

...maybe for better visual help see the fan position and heatsink fins direction on helispectra vid...

https://www.rollitup.org/t/led-companies-w-links.486179/page-135#post-11767072

...for my pov the fan put some fresh air on led zone or reflector zone too...

...please note ....its only my opinion... take on positive side... i like the diy...

pd... and i prefer individual switches for the drivers on lamp... ive only see one switch.... but maybe its a conmutator and go ok for contol the individual divers too... offcourse ...depend on diferent models on conmmutators used...

okok...on second and better look... i saw two switches... the other is the ac conector...dimm to 50% ......

pd2... and with the b models you can go with various system for dimming...
...sds talk about these sistems on her thread about meanwell 3 -1 functions...

...the pot and the resistors are cheap pieces...

my inexpert pov on electronics circuits...first try the breadboard way for tests with multimeter.... and if go ok ...go on prototype pcb way soldered... or other diy pcb way...

...the dimm wires are on DC side... offcourse pay lot of attention on safety when deal with ac or dc live wires... more attention or care with AC side too...

...and sorry for my bad and short english...

e function desactived...thanks Rahz...

pd3... Rahz...i prefer individual switches way ...one switch for driver... or commutator way too...and two separate pots with resistors limited for dim the drivers individually... cheap not too complicated for my pov and with lot of diferent options...
...lol... or 3 pots and use the third for dim all drivers at the same time... a bit more complicated... but not too much for my inexpert pov...


Saludos

very nice build. Just a quick question, you say the fans are both pushing air into and over heatsink? Where is this air exhausting? Is there a vent somewhere for the hot air to be pushed out from that we cant see in the pictures?

CanadianONE said:

very nice build. Just a quick question, you say the fans are both pushing air into and over heatsink? Where is this air exhausting? Is there a vent somewhere for the hot air to be pushed out from that we cant see in the pictures?

Click to expand...

fans are working in a push/pull configuration, i hope!

guod said:

fans are working in a push/pull configuration, i hope!

Click to expand...

I would hope but in his original post it does state "Two 120mm fans each with their own 12w power supply. Both fans are pushing through the same channel so if a fan or fan supply goes bad the lamp keeps running without much change in CFM" which is why I ask.

Very nice Rahz, I have been considering a similar inline cooling set up for my next upgraded light. I was thinking of using 4" chunks of the 4.6" heat sink though.

CanadianONE said:

I would hope but in his original post it does state "Two 120mm fans each with their own 12w power supply. Both fans are pushing through the same channel so if a fan or fan supply goes bad the lamp keeps running without much change in CFM" which is why I ask.

Click to expand...

Jepp!
But later he says one takes in and the other is blowing out.

"Air enters through one fan and out the other."

Sorry for the confusion, yes one is pushing air in and one is pulling air out.

Salmonetin, you are correct about the U vs I path. A bend in a conduit will increase the static pressure needed to move a specific volume per time the same as making the conduit longer or thinner. However, the heat sink I'm using has 1.6" fins so trying to use the I configuration wouldn't be effective. As a substitute I tried to make careful selection of fans. There is another profile at heatsinkusa that has 3" fins but it is a good bit heavier and a 36 inch piece would run over $100 and still not be perfect for a 120mm fan. Maybe 92mm would work but then less airflow or more noise, etc. For such a configuration the best would be a bonded fin heatsink. I don't know where to buy 36" bonded fin heatsinks, much less a single or small order. It would be great if I could source something like that.

As far as the switches, one is the power switch that controls both drivers. The other switch regulates the drivers at 1.4 amps or .56 amps. Having that as a dimming function negates the need to operate both drivers separately

coolbreez1 said:

Very nice Rahz, I have been considering a similar inline cooling set up for my next upgraded light. I was thinking of using 4" chunks of the 4.6" heat sink though.

Click to expand...

Thanks, and I think using chunks would work fine depending on how many, fan speed and pressure, etc. It's not an exact science for some situations... estimation and experience can also produce good results.

Rahz said:

Sorry for the confusion, yes one is pushing air in and one is pulling air out.

Click to expand...

how do you think it would perform heat wise if you set both fans on push, and add exit vents in strategic locations ? perhaps an exit at each end and one in the center top?

just exploring options

It would work better for sure. Either 2 heatsinks with a 2.5 inch gap between them and the air exits through the side, or two (or one) fans in the middle top pushing out both ends. There are other ways. Plus, running fans inline doesn't increase the CFM, only the pressure. Running the fans separately there would be twice as much airflow and every cob on the heatsink would have a lower temp reading.

The downside is what happens when a fan fails? Some cobs not near the fan could easily start to overheat. With a semi passive design, it's not an issue. With an enclosure the situation changes. An inline setup insures the whole heatsink continues to be cooled if one of the fans goes bad, just at a slightly higher temperature.

That is the only reason I went with the inline setup. The question is, is the performance drop worth the insurance? The difference between the lumen output for a Vero 29 (1.4 amps) at 25C and 50C is about 400. In a 75-80F degree room, hottest cob would be about 40, so I'll guess on average I'm 200 lumens short from 25C temps. If I could get temps very close to 30C then I would gain maybe 100 lumens per cob for a total gain of 600.

Inline option: 43000 lumens
Split fan option: 43600 lumens.

I would like to get that extra 600 lumens, but it's a small percentage gain. Perhaps not worth loosing the insurance over?