Calling out to Weezard for LED advice

[DreadedHermie]

Fired up all the lights, no fans. Passive cooling only. Within half an hour the temp of the sink, measured behind an LED, was pushing 120 deg F., so I connected the fans. (These are Zalman ZM-F2, which are 2500 RPM @ 12V. Pretty quiet, just $5 each.) I've got 'em wired to a 9V wall wart, so they're really just loafing.

I watched the temperature drop back down to ~100 deg F. in 10-15 seconds. It was like you dipped the thermometer in cool water. :thumbsup:
[attachment=o214262]

Right now I've got just one fan running. They're kinda mounted diagonally, and I've got the thermometer as far away from the fan as possible, and right behind an LED--a worst-case scenario. Temp's are holding right at 100 deg F. with just the one fan running @ 9V. [attachment=o214263]

Probably the way to do this is wire the second fan to a thermal switch on a separate power supply as a backup.

[attachment=o214264]

[Weezard]

Dang! I've killed so many of those things I feel personally responsible for pushing them to the brink of extinction. Looks like there's 38 left. The 10W deep reds are more expensive....:wtf:

And you'd have to drive them at their abs max to get the same 2.5Watt output that the 15W. get while cruising at 1 amp.
Scored 10 of da buggahs for $290.
Ouch!
Now I eat catfood for a week.

Toodles
Weeze

[Weezard]

:jumphappy:
Now that, is a thing of beauty, son.

I'll wager that it beats a Procyon.


See ya tomorrow.

Weezard be proud of the dang human pupil.:jointsmile:

[DreadedHermie]

Both of the Meanwell's are quite warm, with only 2 leds on each one. I may mount them on the wall outside the flower room with the case open like this and put a small fan on them, blowing on these metal guard plates (which are probably heatsinks, too). Weezard, do you think that's worth the effort (not much effort, really) or is it possible the plastic case is designed to dissipate heat???
[attachment=o214265]

Did you ever find a source for lenses?

Nope. My space is so small, the white walls are reflecting things around nicely, and the light's going where it should so I don't think I'll need 'em. I'll keep my eye out for 'em for you, though.

[Weezard]

Both of the Meanwell's are quite warm, with only 2 leds on each one. I may mount them on the wall outside the flower room with the case open like this and put a small fan on them, blowing on these metal guard plates (which are probably heatsinks, too). Weezard, do you think that's worth the effort (not much effort, really) or is it possible the plastic case is designed to dissipate heat???
[attachment=o214265]

I'd meter those sinks for a voltage difference.
If they are isolated or grounded, I'd stick a cpu fan on 'em and keep them out of the grow room.
Got my drivers in the room, but they are inches from an exhaust fan.

Nope. My space is so small, the white walls are reflecting things around nicely, and the light's going where it should so I don't think I'll need 'em. I'll keep my eye out for 'em for you, though.

Mahalo!
I'll see if I can hunt some down for a side by side test.
My good meter, (CT1330B), reads LUX but will let me compare lensed and unlensed light intensity at 12" etc.

My eye-nose-n-lung meter reads Dankness units,
Weeze

[Neural]

Scored 10 of da buggahs for $290.
Ouch!
Now I eat catfood for a week.

Toodles
Weeze

Do I smell a project in the works??

Hermie- that's a nice light you got there it's making me excited to get my project done. That's one enormous heat sink too.

My bench power supply should be coming tomorrow and I have the ear of a electrical engineer so that should offset most of my newbness.

[DreadedHermie]

And you'd have to drive them at their abs max to get the same 2.5Watt output that the 15W. get while cruising at 1 amp.

Weezard, is this a typo? You could get 12.5W @ 1A if you pushed with 12.5V.

I'd meter those sinks for a voltage difference.

Like a difference in voltage potential between two drivers that are operating? Would you set the meter to VDC and probe the sinks on the 2 drivers? Not sure what you mean here.

If they are isolated or grounded, I'd stick a cpu fan on 'em and keep them out of the grow room.

Measuring here for continuity between the ground pin on the supply cable and the sink? Checking for any leakage / continuity between input and outputs? Sorry, I'm not sure what you're investigating here. :detective1Remember, I have electrocuted so many leds that the replacement ones all have the governor's office on speed-dial!:wtf

Directions for Hermie:
1. Set meter to range __________
2. Place probes here ___________ and here __________

[Weezard]

Weezard, is this a typo? You could get 12.5W @ 1A if you pushed with 12.5V.

Nope, I was refering to the actual light output as listed in the chart on the ledengin site.
For some arcane reason, they measure output of UV and deep red in Watts rather than lumens.

Like a difference in voltage potential between two drivers that are operating? Would you set the meter to VDC and probe the sinks on the 2 drivers? Not sure what you mean here.



Measuring here for continuity between the ground pin on the supply cable and the sink? Checking for any leakage / continuity between input and outputs? Sorry, I'm not sure what you're investigating here. :detective1Remember, I have electrocuted so many leds that the replacement ones all have the governor's office on speed-dial!:wtf

Directions for Hermie:
1. Set meter to range __________
2. Place probes here ___________ and here __________

Stop, yer kiliin' me.

With the supply off and unplugged, check resistance between both/each heatsink and both ouput pins, in both directions.
Then, fire it up and check for dc/ac voltage between both the sinks
(Can't imagine they'd use two seperate sinks without a good reason).
If you find anything at all. use an insulator between the sinks and your CPU fan is all I'm sayin'.

Mo' betta?
Weezard

[DreadedHermie]

Even with all the power supplies in the little flower closet I only need to run the exhaust fan for a few minutes every half-hour or so. :thumbsup:

Some figures, for those that like 'em:

I multiplied actual drive current x voltage for the individual leds to figure watts consumed by JUST the leds. I unplugged each driver/led combo and noted the decrease in watts drawn on my "kill-a-watt" device to determine total watts consumed by the system.

2 red leds only............. 25W
w/ PLN 60-12...............32W

2 blue leds only............ 34W
w/ PLN 60-12............... 39W

4 red leds only............. 48W
w/ Mastech 30-10........ 69W

Total "led lighting watts" = 107W (89% of rated abs max)
Total power consumption = 140W

I think pushing the drivers a tad harder will increase the efficiency a bit. The Mastech's just idling--it's cool, and the fan never comes on. I love this thing! Same price as a Meanwell 150W driver. Maybe I'll get another one and drive my 12 reds with 2 Mastechs. Have to see how close Vf is on the next batch to plan for proper drivers. Just using 3-4 leds per driver might be good insurance, tho...

Weezard, I've got the light about 9" above the plant tops. Does that sound about right, or can it be closer? (I have the Procyon about 12" up.) Seems like I remember you mentioning 3" but can't remember the discussion....:stoned:

[DreadedHermie]

(Can't imagine they'd use two seperate sinks without a good reason).

They looked like steel, if that tells you anything. They are positioned so Hermie couldn't get his fat fingers in there to get poked, so they are functional in that regard. :thumbsup: (Where's my butter knife?? I'll find some life in there!)