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Cheap Lighting ideas?

Guess we should get hold of par meters after we get some builds done to see just how bright they are. The TMC mini 400 is what 12watts? And they aren't Crees. So four Cree XM-L 3w LEDs should better one of them. I believe the 10w LEDs output about 1000lm at 700mah. So I'd say they are capable of growing plants. Would be nice to have some par readings tho.
 
Hi all,
Garuf said:
If you're on the market for t5's I've heard nothing but good things about these for the money. Lightwave t5 2ft 2x24w [LIGHTWAVE T5 2FT 2X24W]
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I've got 11 of the 8 x 54W 4' units of these in the glasshouse and they seem pretty reliable.
rolexbene said:
Have you seen these badboys for a wire free look.
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I didn't know about these either, and they look very useful, is there a UK based retailer?

cheers Darrel
 
wazuck said:
I'm unable to see the item but I did a similar search and I'm liking what I'm seeing. Just remember that mixing different colour leds will give you a better colour rendition so those boards are perfect. I may well buy one to play with and see what I can come up with. dialed down LEDs on them with a nice DIY controller etc built Into a well made enclosure would be really nice. Such a good find. I'm a bit obsessive when it comes to lighting. I've been looking into building an Ati style t5 dimmable luminaire. What driver are you using then?
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Well bout the driver a while ago for about £6 I think, its basically a dimmable version of this comes with a potentiometer to dim it that I can build in to the stand:
36W LED Driver Power Supply for 7-12 x 3W LED 100-240V | eBay
Also going to give these a go for testing, not as bright as crees but will give off less heat and for the price can't complain.
10pcs 3W High Brightness LED Beads LED Lamp 180~200Lm Cool White 3.6~3.8V | eBay
Also these pcb's are only 11mm wide so would fit in to recessed aluminium profile bar with 3w led's.
This place offers recessed aluminium profile bar with free shipping for a good price and would fit the pcb
1m Flat Recessed Aluminium Profile/Extrusion + Clear/Frosted Diffuser, Profiles, Extrusions, LED Profiles, LED Extrusions

Other cool unrelated lighting to look at are these sick cree mini torches, got one on my bike and its brighter than the cars:lol:
New 1000lumen TrustFire Mini CREE XML T6 LED Flashlight Torch Keychain+Battery | eBay

And these bulbs are sick too:
VINTAGE ANTIQUE LARGE FILAMENT E27 EDISON SCREW GLOBE LIGHT BULB 125mm 40W BNIB | eBay

Also the one of the best led shops on ebay is this one:
1 3 5 10 20 30W HIGH POWER LED, Luminus SSC CREE items in LED-DNA store on eBay!
 
Just came across these
a6u2udyh.jpg
They are Cree XP-G 6000k search lights. That one is 36x3w so 108w @6000k. 25 degree beam angle. 7200lm. The warning says looking directly into the light can cause instant blindness. I'm sure with a little bit of tinkering that would be a nice light. It's IP 65 rated. So just really needs to be dimmable as that is far too much light. Even if it was mounted on your ceiling 😉 anyway the auction ends in an hour and it's on £17 so it is on the cheap end for lighting solutions 🙂
 
Bene. I like your pcb board idea a lot. I think I'm going to have a go. I like this board
qupydyny.jpg
20 LEDs I would probably have to run 1w or even 0.5w LEDs to keep the light down. Just searching for the right mixture of LEDs now. Does anyone know if say I had 100lm LEDs. Would having 2 make it 200lm or would you lose some? Cheers.
 
So my thoughts on the LEDs are to use an equal mix of warm white and blue LEDs as they should balance out nicely and possibly adding in some greens. Then the rest as cool white or even 10k+ to give it a temperature closer to what takashi has for his halides. That should give a nice colour rendition. I'd estimate that each pcb setup would cost around £20 at most. The options would be either 0.5 or 1w LEDs so each unit could run as a 10w or 20w. 20w would probably be too much light and would be throwing out around 60w of T5 equivalent light as an estimation. I'm not sure what the shimmer would be like as I normally use 3w+ LEDs. The colour mixing shouldn't be a problem as no optics would be added. Anyone got any input?
 
wazuck said:
Guess we should get hold of par meters after we get some builds done to see just how bright they are. The TMC mini 400 is what 12watts? And they aren't Crees. So four Cree XM-L 3w LEDs should better one of them. I believe the 10w LEDs output about 1000lm at 700mah. So I'd say they are capable of growing plants. Would be nice to have some par readings tho.
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Just to correct you they output around 1000lm at 3a this is the problem I am having is finding a suitable driver that will output around 2.5a (2500mh). the only decent solution I can find are drivers for use with batteries, but I am not massively electronically competent so could do with some advice I anyone knows of a solution.
 
What heat sink and mounting you think wazuck? my biggest problem is having an open top look but finding a mounting solution. ceiling mounting would be the easiest but my ceilings are too high to run wires and look good IMO.
 
Well aslong as the LEDs are well under driven the heat sink shouldn't be a problem. You should be able to get away with a very slim fixture. The more powerful the led tho and the greater the cooling needs. I would like to say those led beads at 1w/0.5w would run pretty cool off just the pcb boards but until I buy my LEDs and my board turns up I won't be able to let you know.
 
Just out of interest. Why have you included a 10w blue led bulb? I would consider adding in some different temperatures of white led. Also these leds need mounting to a heatsink for the cooling. Be it a big heatsink or a small heatsink with a fan is your choice.
 
I added blue, firstly its my understanding the blue part of the spectrum is used for a large part of photosynthesis and secondly as this is an experiment and i kind of like a bluish hint so why not 🙂 I have tried with red LED strips, but it makes things look pink. we will see how it looks, might look with rubbish with the blue.

I have a newish CPU heatsink i have be using for testing, but i am considering a few Arctic Cooling Alpine 11 GT Rev.2 Quiet CPU Cooler - Aria Technology
 
Yeah I guess the blue would give you a marine look. 5a driver so I guess you would need to run 6 of these 10w led's in parallel. It's funny as all the drivers I have been looking at keep the amps at a constant and change the voltage to run the led's in a series circuit, still either should work ok. you will need some monster heatsink for this one though, you can get them in a single aluminium heat sink quite cheep from china if you don't mind waiting a couple of weeks for delivery, then make a single hanging unit similar to ones sold for big £, however this all depends on how you want to mount these badboys. If your going to be using fans, it might be worth looking in to how many amp these take up and integrating them in to the 12v circuit, to save on running more cables. Goodluck and let us know how you get on.
 
wazuck said:
Well aslong as the LEDs are well under driven the heat sink shouldn't be a problem. You should be able to get away with a very slim fixture. The more powerful the led tho and the greater the cooling needs. I would like to say those led beads at 1w/0.5w would run pretty cool off just the pcb boards but until I buy my LEDs and my board turns up I won't be able to let you know.
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I have ordered some PCB's and some cool white 3w led's, and am going to order some 4mm aluminium strips as heatsinks, if all go's well with this I will sandwich the bar in between some bent acrylic to form a aquasky look, maybe a bit of braided lighting cable to finish it off. Just wanted to say if you have an excess of leds that are not cool white spectrum, I can do you a swap if you want, need to mix it up a bit but don't want to buy loads more.
 
Rolexbene,

Its my understanding (i am new to this LED/electronic lark) you run LED's in series up to the voltage i.e. 4 x 3volt LEDs in series = 12v for a 12 volt driver/power.
In this case the driver is 12v and so is the LED, so its parallel and the LED gets the full voltage. As they draw 900ma you could have up to (5000/900) 5.5 x 12 volt LED's or i have made a mistake 🙂
 
LED's are driven by current NOT voltage (unlike a normal light bulb), thus all this talk of what voltage LED's require is wrong. In terms of water (as we are all involved in aquariums) voltage = water pressure and current = flow rate. LED's require current ie so many litres/second in water terms, not pressure ie bar or PSI.

So a to connect more than one 900mA LED, you wire them in series so each one has 900mA passing through it. If you wire them in parallel, from say a 900mA LED driver, you will probably end up with one bright'ish LED (hogging most of the current) and all the rest dim (taking the remainder of the 900mA current).

Mikster, that PSU is not suitable for driving LED directly as it is constant voltage (12V), if you connect it directly to LED's the LED's will draw the wrong, most likely huge, current and either burn out instantly or get very hot and burn out very quickly. In fact the Ebay advert says the 12V supply is "For the Led Lights Strip Power Supply". Thus you connect the 12V supply to LED light strip power supply, which I assume supplies a constant current, and then to the LEDs.
 
So this thing is a power supply for another driver (or something similar) that would explain the incredible heat generated by the LED when i tested it.

This is entirely hypothetical, if this power supply (not driver?) feeds a 12v LED, the LED will draw as much current (flow) as possible until it burns out, heat or otherwise, so what it needs a is a resistor in between to limit the current or flow? Although i wouldn't have a clue how to calculate this. BTW i am not proposing using this thing anymore.

Making a massive assumption here again, but the LED strips you can get look like they have resistor every couple of LEDs, is that to limit the flow?
 
ian_m said:
LED's are driven by current NOT voltage (unlike a normal light bulb), thus all this talk of what voltage LED's require is wrong. In terms of water (as we are all involved in aquariums) voltage = water pressure and current = flow rate. LED's require current ie so many litres/second in water terms, not pressure ie bar or PSI.

So a to connect more than one 900mA LED, you wire them in series so each one has 900mA passing through it. If you wire them in parallel, from say a 900mA LED driver, you will probably end up with one bright'ish LED (hogging most of the current) and all the rest dim (taking the remainder of the 900mA current).

Mikster, that PSU is not suitable for driving LED directly as it is constant voltage (12V), if you connect it directly to LED's the LED's will draw the wrong, most likely huge, current and either burn out instantly or get very hot and burn out very quickly. In fact the Ebay advert says the 12V supply is "For the Led Lights Strip Power Supply". Thus you connect the 12V supply to LED light strip power supply, which I assume supplies a constant current, and then to the LEDs.
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What are you talking about if you wire 4 3v led's in series they will draw 12v, this is why they sell drivers that are rated from "30-70v 12-20 x 3w" Not sure if this is the same Mikster driver, but this is exactly how most of the 3w led drivers work. If you don't believe me just look at the top of this standard led driver:
60W LED Driver Power Supply for 12-20 x 3W LED 100-240V | eBay
 
LED's do not have a rated voltage, you don't get 3V LEDs (OK might get 5V & 12V but they have a resistor in), you get so many mA LED's, so your statement "4 3v led's in series they will draw 12v" make no sense. In water terms, "4 3psi things in series will draw 12psi" 😕

What happens is when you pass the rated current through the LED is drops a voltage, thus @900mA will drop 3V for instance. Note however this voltage depends on temperature at the rate of -2mV/°C so will be less as temperature rises. So connect 4 LED's to 12V, will most likely draw more that 900mA and as they warm up will draw more current until they are destroyed.

The driver rated at "30-70v 12-20 x 3w" means that it will drive 12-20 3W LED's in series ie varying the output in the range 30V to 70V so as to always put 680mA through the string of LEDs.

I fear you also might be confusing V - Voltage with W - watts (power).
 
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