New LED Fixture PAR readings

S2minute

New member
Guys n gals, this pic is REALLY poor but i'm going to have better pics sooner or later heh :headwally: . Anyway, i just bought an Apogee sensor to use with my MM. I'd like your opion on the readings please. This is a DIY LED Fixture i just recently finished and replaced an old MH system. Pics and details are written on my album in my profile if your interested. http://www.reefcentral.com/forums/album.php?albumid=6453&pictureid=44496
 

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Can you give us a little more info about your light setup? How many of each type of LED, drive currents, etc.

Those numbers look very high. I would think you should be able to keep pretty much everything.
 
If you look at the Brown Acro,(it's purple now), where the par reading says now 450. Notice how it grew? The MH ballast for the left bulb died on me so the acro grew towards the 2 remaining good but, VERY old ones. I just refused to get a new ballast and bulbs being i was so close to finishing the new fixture.
 
Can you give us a little more info about your light setup? How many of each type of LED, drive currents, etc.

Those numbers look very high. I would think you should be able to keep pretty much everything.
Oh yeah sorry, i have all that typed in the albums too but here ya go:

It's a 6' fixture made from a weilded aluminum frame. The 2' sections on each end are bent at a 15 degree angle so when i get an adurno made and programmed it will help the sunrise/set effect. I bought 17" aluminum bars from Fishman,(24 of them), and cut them down on a table saw and miter/slider just like he did to make his HSs. Then i drilled/tapped each of the 144 HS pieces. Each LED is mounted on it's own HS and the HSs to sheathed cable which is strong enough to support the HSs but, flexible enough to enable me to bend and twist each LED in nearly any position i want. The is a series setup using CAT4104 driver boards.

Total of 24 strings of 6 LEDS: Broken down is this...

3 strings of XM-Ls @ 1400ma These are a combination of T6 CW(coldwhite) and T3 WW
One string per 2' section and they run the length of the fixture right down the middle. I only have them on 2 hours at noon atm.

21 strings of 6 XP-E RB and XP-G white @700 ma: They run purpandicular to ther XM-L strings.

9 of the strings are all RB,(3 per section).
12 strings of 4 RB and 2 white,(1 NW and 1 CW,(cool white) ).

3 PSs: 1 SP-320- 24 for the RB strings...and 2 rb/wt strings
1 SP-320-24 for the rest of the RB/wt strings
1 Sp-100-24 for the 3 XM-L strings

The outside LEDS have 60 degree lenses. All the rest have 80 degree lenses and the fixture sits 7-10 inches above the surface.

Since the tank is a 175 Bowfront, the bow part was a bit shaded because the fixture is a rectangle shape so i attached an existing 2 bulb VHO 4' setup to the inside in the canopy lid. One 03 Atinic and one Atinic white. That helped.

You can see the new fixture in detailed pics in my album.

I seem to have misplaced my math sheet for the way i figured the currents ect. .. i know i diden't throw it out. I'll look harder later. On and off over the past year and a half it was a HUGE learning exp for me. I never did anything like this before and to jump right into a huge build like this was prob a mistake but it turned out really well. If it wasen't for the guys on the DIY lighting section, i'd never of been able to do this. Tons of questions, READING, studing and of course...patience and TRUST :). I gave Fishman about $1200 for parts(leds ect.), in a group buy. The versility of his DIY led setup inspired me to invent one of my own. So, i did :crazy1:
 
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Quick comment passing through - keep in mind the apogee sensor doesn't read the PAR spectrum in a linear fashion - it typically under-rates LED PAR.

BY how much Willi?? Is it significant?? Or something not to be overly concerned about? ..and is there a way to get a more accurate figure?
 
There are threads with math if you're super curious - it will depend on the exact specs for your fixture. Or you can ask the vendor to provide you a response curve, and map it to the spectral plots for your LEDs and come up with the math yourself. But to me the number is relative anyways, so I wouldn't bother unless you're trying to do a very specific match/comparison to some other light rig.
 
There are threads with math if you're super curious - it will depend on the exact specs for your fixture. Or you can ask the vendor to provide you a response curve, and map it to the spectral plots for your LEDs and come up with the math yourself. But to me the number is relative anyways, so I wouldn't bother unless you're trying to do a very specific match/comparison to some other light rig.

prehaps i'll look into it...untill i get completely lost :wildone:
The only thing i have observered so far is a couple of LPS had a fit so i moved them further down. I have a Porties too that got pis*y because the top portion of it is laying at 180 degrees in mid column. The rest of it is at a steep angle and doing fine. I think they will all recover though. They all seem to be holding their own atm. However compared to what they were adjusted to in the first place it's no wounder they reacted. Time will tell and i'll keep an update going like once per month and hopefully get a way to take much better pics in the meantime. Thanks Willi :)
 
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