DiY LEDs - How to Power Them

My new light has dimmable power supplies. Where do I buy the dimmer. Will I have to order it or would a store like Fry's have them?

Some type of programmable dimmer would be sweet.
http://www.cree.com/Lighting/Products/Indoor/Controls/Smartcast
Something similar to this.

SupraSPL said:

There would be no problem running it at 92% load. If anything you might get a slight boost in efficiency.

Because it will be a high voltage circuit a small wire can get a lot done. As long as the jacket of your wiring is rated above the voltage of your circuit, 18 gauge will be more than enough because it is only carrying 700mA and probably not a very long distance.

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Even with the little bit of 28gauge fused between the connector and the 18 gauge wire? It's about half an inch or so.

That is a good question about the 28 gauge. You could hook it up and see how hot the 28 gauge section gets.

Tazbud said:

No hiding another newb question but can anyone suggest the most efficient way to run a single cxa3070 from 12v (at a decent power output, 1400ma+ the more the better, I have excess solar + going to waste but it's limited) Would I be better wiring the batteries to amp up voltage (48V?) or a sine wave convertor, I see they are not very efficient at all. The meanwell drivers I have are lpc 60-1400 & 1050 I (now) have... to dip my toes... need 90v min startup it seems. Or could they run directly through some sort of resistor. I want to make a light bar but have access to a bank of batteries all running at 12v and largely power to waste... could use a 12v veg light ; )

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nevergoodenuf said:

Taz- I have used a car battery and an 750w inverter, from HarborFreight, to power my room when the power was out. Needed it for a few hours and worked fine. Sounds like you could run everything off your 12v source.

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The inverter is good for a power outage but if you want to permanently power it from 12vdc, a better way would probably be to get a DC step up driver. Converting from 12vdc to 120vac to 42vdc seems inefficient, your already running DC from the solar just use something like the Meanwell LDH-45A-1050W ($11 @ Jameco). It is a dimmable DC constant current step up driver that will output up to 43v @ 1050mA. I don't know of any that will do 1400mA+ but they probably exist.

I had to go back to find this quote...

SupraSPL said:

The Mean Well maxes out at 143V. So if you run it at maximum current (~1500mA) you could only run 3 CXA3070s. The 143V limit is a hard cap, we found this out from the HLG-185H-C1050A.

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So the HLG-185H-C1050A you say is capped at 190V. Say you dim it to 700mA, Does it allow you to use a higher voltage closer to the 286V the -C700A would be capped at?

MrFlux said:

The Mean Well HLG-185H-C1400A driver...

The light is adjustable from 74W to 210W (230V AC power), or 67.3W to 198.9W LED power. This means the driver at max power is over 94% efficient, which agrees nicely with the spec. The other nice thing about this driver is that although it is rated for 1.4A @ 143V, it will give a higher current at lower voltages (up to a point), so as to maintain 200W output power. For this light it's 1.528A @ 130.2V. It's as if Mean Well thought "hey you payed for 200W so that's what we're gonna give you". Very thoughtful.

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MrFlux says when you use less voltage it opens up more current, though I thought the current would have been capped at 1.4A.

Basically what I am asking is if I dim the HLG-185H-C1400* down a bit could a run 4 cxa's off it?

I guess if I dim them enough that each cob's draw is less than 35.75 Vf I should be able to run four, I just can't max them out. I still haven't decided on which ones to get.

epicfail said:

the Meanwell LDH-45A-1050W ($11 @ Jameco). It is a dimmable DC constant current step up driver that will output up to 43v @ 1050mA. I don't know of any that will do 1400mA+ but they probably exist.

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Awesome find thnx!

epicfail said:

So the HLG-185H-C1050A you say is capped at 190V. Say you dim it to 700mA, Does it allow you to use a higher voltage closer to the 286V the -C700A would be capped at?

Basically what I am asking is if I dim the HLG-185H-C1400* down a bit could a run 4 cxa's off it?

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190vf remains the cap, but when dimmed the COBs have a lower vF so you can squeeze more of them on the string. Yes I believe if you dim the C1400A you could fit 4 3070s, although I am not sure how far you would have to dim it. If it is below 1150mA then you would be better off with a C1050A (which outputs up to 1150mA at 191vF).

Thanks very much epicfail. Yes! That was what I was looking for. I did start searching meanwells line up but was a bit lost. They do seem to offer other current regulated drivers as well..and up to 90% efficient..

epicfail said:

The inverter is good for a power outage but if you want to permanently power it from 12vdc, a better way would probably be to get a DC step up driver. Converting from 12vdc to 120vac to 42vdc seems inefficient, your already running DC from the solar just use something like the Meanwell LDH-45A-1050W ($11 @ Jameco). It is a dimmable DC constant current step up driver that will output up to 43v @ 1050mA. I don't know of any that will do 1400mA+ but they probably exist.

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I might as well just ask, sorry i'm not lazy. I forget things I don't use every day... I'm largely ok before the first bake..

So, for the sake of keeping things simple lets say 100w panel feeding a 100amp battery (12v). Working on 7hrs good sunlight and allowing for inefficiencies there should be (very) roughly- 50 amps into that battery each day. Is this a simple conversion ie.

So.. (for the exercise) A cob running @ say for ease- 36v /.5amp up to 18hrs x .5 (amps) x3 (12v-36 conversion) = 27/12v amps used each day.. i'm not entirely sure amps are even the correct measure- amp/hours, perhaps (?) I need 27(12v) amp/h for a cob running 36v/18hrs in which case 1 3070 cob driven @ .5amps.. off a 100amp battery reserve & 100watt panel for up to 18hrs/day.. 2/3 cobs would leave some reserve?

nevergoodenuf said:

My new light has dimmable power supplies. Where do I buy the dimmer. Will I have to order it or would a store like Fry's have them?

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The drivers in your fixture are the Meanwell HLG-240H-48B which can easily be dimmed with a 100K ohm pot but since there are 2 of them in the fixture your going to want to get a 50K pot to control them both at once. The problem I am seeing with the above picture is the wire colors, according to the spec sheet the dim wires are blue(+) and white(-). Your wires seem to be brown(+) and blue(-) if I'm reading that blue wire correctly (0-10v -). Those must be a lead wire connected to the blue/white coming from the driver, but is it connected to both drivers? You might have to follow the wire to check.

You can also dim with PWM 1-10vdc led dimmer unit but they can be expensive. If I was to do PWM dimming I would use a Arduino or a similar micro controller with a RTC. It would be cool to have the light fade on in the morning and off at night, maybe create some mid day fading to simulate clouds and fight plant depression. I think I read that in one of SDS threads, sounds like an interesting test for a micro cab project if someday I have spare time.

Just to say on the battery front, working on 3 x 3070 run 12hrs through 1050mA drivers (from 12v) and a few small 12v fans-
I get a battery capacity of around 225ah (leaving 50% in reserve) powered from at least 270w solar.

Just to say that after much staring I get:
At least 230w from solar panels (15.3a x 7.5hrs/12v)- feeding, at least, 225ah battery bank (leaving 50% in reserve for 12hrs lighting) will power 3 x 3070 @ 1050mA .. (/12hrs)

+ a few small fans -

to buy, costing $700-$900 initially, for panels/reg/batt/drivers and + around $100 p/a to maintain

edited ; )

Taz you should do a thread giving a rundown on your solar panels: parts, connections, ratings and such. You'd be taking up responsibility answering (at least) my dumbass questions but I'm sure there are a few of us that have wanted/would want to start something.

Props to you for taking the steps to be electrically savvy.

Scotch089 said:

Taz you should do a thread giving a rundown on your solar panels: parts, connections, ratings and such. You'd be taking up responsibility answering (at least) my dumbass questions but I'm sure there are a few of us that have wanted/would want to start something.

Props to you for taking the steps to be electrically savvy.

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Sounds like an awesome combo, would still be difficult (costly) to run a lot of power, but highly efficient LED's and DIY solar sounds like an opportunity for some enhancement, or a slam dunk for running low-draw or temporary lights like initiators

I might grab a driver and give it a go, might have enough gear already to power one cob .. though I also think those figures are a bit hopeful.

I'd agree, might be ok for supplemental greenhouse lighting, stealthy cabinet. To make most use of the aging batteries- continuous running.

Never taken much notice before, we only use the panels for occasional lighting, but being told to expect only 2/3 hrs of full panel power in winter (not 7/8..) In that case could be more like a330w panels/330aH batteries and for only 1-3 cobs

I am on my second indoor grow. This time I changed my cfl lights for 6, 10 watt led lamps. I find they give more light and better growth from my plants.

not really a "how to power" question, but... it could potentially become one.

few CXA3070 versus many XM-L2. Go!

(i realize the xm-l2 are much smaller and would obviously require more intricate soldering/wiring and probably a more complex circuit, but it would seem that the xm-l2 are the top of the efficiency food chain, so wondering how you experienced types feel about the comparison, or whether it's even a "fair" comparison at all... among other things! ...and any helpful discussion on the matter)

reasonevangelist said:

few CXA3070 versus many XM-L2. Go!

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Both are efficient emitters - there is a great thread on here called "cxa analysis" to see a good comparison.

The cxa concentrates heat into a single spot and acts a light point source -very different to an equivalent wattage of xml2 on 20mm stars.

And pointing out the obvious: it is a billion times easier to build and cool a few cobs than a few hundred 20mm stars.

Thinking about XML2 for my micro mom/clone chamber though - cobs need a bit more headroom to cover a given canopy.
Xml2 currently cheapest on fasttech http://www.fasttech.com/products/1609/10003889/1574600 - nice bin

Cxa best sourced via official component channels

Supra, Posi, Scotch and myself (and therre are probably otherz...but the DIY crew are growing...i cant keep up ) have incorporated both COB and xm-l2 emiterz in our buildz...

For myself... i wanted a few more 'supplement whites' and more blue (xm-l2 4200k's) to go with my 'primary light sources' 3000k COB'z...

As some people asked me how I wire my led lamps, this is how, I bought 6 10 watt outdoor LED security lamps costing about 15 euro each, a roll of 3 core cable costing 25euro, and a house hold trip switch costing 7 euro. I wired them in line to the trip switch, from my trip switch I wired my 240 volt power supply to a wall plug and timer. If you can wire a plug you will have no trouble getting this sorted. 1 plug with a 13 amp fuse will be enough to supply all 6 lamps as its only 60 watts of power. My plants are growing faster and bigger since I changed from cfl to led, and I'm using far less power. The photo i posted is of a 12 day old ak47 plant growen under led lamps.