Page 1 of 2

Cree Strip Build

Posted: Fri May 25, 2018 6:52 am
by alienfarts687
I finally managed to get this assembled more or less to my satisfaction. I'm waiting for the drill to charge so I can widen the holes in the middle for airflow, as suggested by sdfoster22.

Parts:
8x Cutter Strips of 112 diode Cree 3030 Series LEDs
ZPE 250w Constant Current Driver
100k potentiometer
4mm thick aluminium sheet (60cm x 60cm)
Auto/marine two-wire cable (2m)
DC plugs for connecting and disconnecting the driver from the light
Extra wire (I reused some of the wire that came with the strips, as they were prewired)
Adhesive thermal tape
Heatsink compound (thermal grease)

I've divided the 8 strips into two groups of 4. The centre is 11cm wide and divides the two groups. There is a strip every 7cm.

Everything lights up and works, including the 100k potentiometer for dimming. It even dims to off! I still haven't figured out how to get a microcontroller to interface with the driver, but it seems to be much more difficult than anticipated, as my ESP8266 (Wemos D1 Mini) runs on 3.3/5v. I can't make sense of the PWM section of the driver datasheet, but if I'm reading correctly, it does 3-in-1 dimming, so 10v resistive dimming or PWM or something else.

I managed to kill a plant and rip a hole in my tent while trying to hook it onto the yo-yo hangers I have. It was like a guillotine. :( Oh well, I probably had too many for the size of my tent anyone. I took a bunch of clones and put them under my now useless blurple. :roll:

I still need some strong S hooks and chain to mount it. I don't think the the yo-yo hangers can really handle that much weight.

I'll post some pictures of the finished light soon. Needless to say, it is VERY bright at "max" i.e. 700mA. Theoretically these strips can go even higher with a more powerful driver and heatsinks...

Re: Cree Strip Build

Posted: Fri May 25, 2018 10:32 am
by alienfarts687
Here's a picture of it all wired up and ready to go! It's now mounted inside my tent with far too much steel chain. I don't know why I thought 2 metres for each side was the right amount!! My tent isn't even 2 metres tall... :lol:
IMG_20180525_154030.jpg

Re: Cree Strip Build

Posted: Fri May 25, 2018 12:52 pm
by sdfoster22
Nice build!

Re: Cree Strip Build

Posted: Fri May 25, 2018 1:45 pm
by LEDG
Sweeeeeeeet :idea: :idea: :idea: :idea: :idea:

Re: Cree Strip Build

Posted: Fri May 25, 2018 2:02 pm
by Sativant
Nice light ! I think the holes are a good idea- but you would need many more, and much larger to contribute to airflow.

Re: Cree Strip Build

Posted: Fri May 25, 2018 3:02 pm
by sdfoster22
Agreed. I would make them larger. Maybe 1/2"-1".

Re: Cree Strip Build

Posted: Sat May 26, 2018 9:29 am
by alienfarts687
I agree. I took it down again during lights out to drill some more air holes, but my drill keeps overheating, so I'll finish another day. Eventually I'd also like to add a small computer fan for a bit of active cooling. That aluminium sheet gets fairly warm, so I think some active cooling couldn't hurt.

Re: Cree Strip Build

Posted: Sat May 26, 2018 9:42 am
by unkle_psycho
I tried the difference with just the weakest table fan moving on lowest power, and it made a huge difference for me.

Re: Cree Strip Build

Posted: Sat May 26, 2018 9:59 am
by alienfarts687
My thinking is that one or two computer fans running on a very low setting should be quieter than the clip fan I have currently. I can also hook them up to an Arduino and control the duty cycle based on temperature as long as I get ones that support PWM. I have one lying around here, but I haven't quite figured out how to use it!

Re: Cree Strip Build

Posted: Thu Jun 28, 2018 12:23 pm
by alienfarts687
I must say I am absolutely LOVING this light fixture. Amazing results. Hopefully I can post a picture of remaining lady underneath this light soon. I'm at about 34F and I really cannot wait for harvest!