how efficient are LEDs really?

[wld1783]

I have 5 LED banks. 3 are driven with BuckPucks, 2 are driven with the Mean Well Driver. The Mean Well pair are brighter to the eye. 6 LEDs are driven by each 1000mA BuckPuck 12 LEDs are driven by 700mA Mean Well. The BuckPucks are on a 24v powresupply and the Mean Well is 48v output.

Bill

 

[TheFishMan65]

wid1783

The buckpucks should be brighter since they have more current. So I was wonderingif you can measure the current coing through each string? Also are the buckpuck driven LEDs alot hotter than the meanwell driven LEDs. LEDs output is lowered the hotter they get, but I would not think that much. If it is visible to the eye that means like 50% dimmer.

Thanks

 

[renisel]

For side-by-side comparison, I don't think you need anywhere near a 50% reduction in light intensity to see a difference. I believe (although I could be wrong) that you are thinking of the necessary change in intensity to notice a difference when a single light source is gradually dimmed.

Regardless, I agree that it sounds odd that the 700mA drivers are creating more intensity than the 1000mA drivers--or are even close. I have played around with a single Cree LED on a dimmable 1000 mA buckpuck and can definitely see a difference as I turn the pot to vary the current over the range of ~400-1000mA.

Just to make sure, are we talking about the same type of LED's with the same optics on both drivers? If so, do you happen to have a multimeter laying around that you could use to determine whether or not the two drivers are actually delivering their advertised currents? I have high-quality multimeters and oscilloscopes at work, but the only thing I have at home is a cheap multimeter that won't measure anything above 500mA.

 

[der_wille_zur_macht]

You're assuming that they're putting out what they say they're putting out. Two different drivers with the same specs won't necessarily perform exactly the same way in practice. I'd be curious to see the results of actually measuring the currents each delivers.

I guess that was my point - something's up if two drivers with the same current spec look different.

I have 5 LED banks. 3 are driven with BuckPucks, 2 are driven with the Mean Well Driver. The Mean Well pair are brighter to the eye. 6 LEDs are driven by each 1000mA BuckPuck 12 LEDs are driven by 700mA Mean Well. The BuckPucks are on a 24v powresupply and the Mean Well is 48v output.

Bill

My guess is you're underdriving the 1000mA buckpucks. If you've got 6 LEDs on each at 1000mA, it probably needs more like 26v to have enough head. If you don't give it enough voltage, it'll just drive at a lower current (since it's a buck regulator, it can't boost voltage, only cut it.)

 

[wld1783]

The BuckPucks were driven at 24V and set the up was based on the RK Mag DYI LED Setup...

An obsolete way but still viable way to light an aquarium

Sorry they changed format and can’t link it quickly.

www.ledsupply.com was featured along with www.heatsinkusa.com

My Guess is we will be arguing about the best LEDs for colour or growth. Not if its viable or practicable in the coming months.

For me I’m sold and recommending them for anyone who asks what’s the best lighting.

The only question is where to get them at the best price.


Bill

 

[nanotank]

I ordered an AI setup today for my new 60 cube. With my profilux plus ll ex the setup should be hard to beat. The lighting options are endless. I also have on order a 24" reefbrite blue led setup. I like blue and this should be a stunner.

 

[wld1783]

Pics are worth a thousand words.

Before 25.2 Amps

After 13.5 Amps

The T5s are driven by IceCap 440s

Bill

 

[wld1783]

Ment to say IceCap 660s

Bill

 

[solos2]

This is a picture from the AI site:

What I don't understand is, the AI module is designed with using 40 degrees optics for strong light penetration over great depth of water. They were really proud about the high PAR reading reported some 20" under the fixture (in air not under water).

But now they're advertising hanging the LED fixtures so high above the tank, like MH units, wasting precious PAR in order to let the light spread a little bit. Why not just hang the LED modules 3" above water and use 60 degrees optics then?

But of course if they use 60 degrees optics then the PAR reading 20" under the fixture won't be as high as the one reported on their site.

 

[g8gxp]

With the optics on the lens the light cone is very tight the closer you get to the light. So if you were to hang it at 3" you would get significant spotlighting effects. Even though the 60 degree optics are on the wider side of the available optics it is still tight at 12" compared to no optics. The difference in PAR (at the sand bend) between optics vs. no optics is gigantic, but the difference in PAR (at the sand bend) between optics at 6" above waterline and optics at 16" above waterline is not nearly as big. Certainly there is a difference, but the drop in usable light is much less drastic.

 

[der_wille_zur_macht]

But now they're advertising hanging the LED fixtures so high above the tank, like MH units, wasting precious PAR in order to let the light spread a little bit

FWIW, With ANY optics, the light from an LED is very laminar, and hence the PAR value doesn't drop off nearly as fast as you'd expect.