Hello,
I posted this at a local board...but I will repost here. The prices are in Canadian.
The originals are at
http://www.aquariumpros.ca/forums/sh...s=&threadid=90
Here it goes......
Objective:
To produce a lighting system that produces the same amount of light as SHO without an Icecap. Around here an Icecap 660 is about $270 each. Pretty expensive for a ballast that delivers 65W to a F40T12.
Theory:
F32T8s (the thin tubes - 1" diameter) -- these lamps produce 2600 to 3000 lumens of output and consume 30W of lamp power. So, it produces 86 to 100 lumens per watt.
F40T12s (the thick tubes - 1.5" diameter) -- these lamps produce 3000-3300 lumens and consume 40W.
VHOs (F40T12VHO) -- these lamps produce roughly 6000-6500 lumens of output. I am not sure, but some manufactures say that their output decreases to 4000-5000 lumens after 1000 hours. These lamps consume 110 W.
PC (PL-L 55W) -- these lamps produce roughly 4500 to 5000 lumens of output and consume 55W.
So, we need a F32T8 that glows as bright as VHOs or PCs...say 5000 to 6000 lumens. Based on F32T8's efficiency of 85 lumens per watt, we need roughly 70W or 240% output of F32T8s. There will be some drop off in the efficiency due to heat - so we might need 80W. How do we do that ?
Each output on the ballast is responsible for delivering power to a tube ... lets suppose we hooked up the ballast outputs in parallel. Say, we had a ballast that can drive 4 seperate F32T8s. If we hooked up all the outputs of the ballasts together...we would deliver about 400% output to the lamp -- or drive the power required to drive 4 lamps in to one lamp. Now...this only really works for electronic ballasts and I waive any responsibility if somebody does this...and burns their reef down or injuries themselves. Don't try this on a magnetic ballast...they work on a different principle.
Materials:
- F32T8 fluroescent tubes (6500K GE - $3.50)
- 4 tube F32T8 electronic ballasts from your local hardware store. I used an Advance REL-4P32-SC - which I got from Home Depot ($30).
- End caps ($3 pair)
- Wire nuts. ($0.20 each)
- power cable - ($3)
How I did it:
I wire all of the yellow wires to one side of the tube and all the red+blue wires to the other side of the tube. This should deliver 4x the output of a single tube. Since 4P32-SC is a standard ballast, it will only deliver 88% of the 30W for F32T8 -- its a standard practice to save power for indutrial/office lighting.
(See attached figure)
~350% (=88% X 4) should deliver 9000 lumens (350% X 86 lumens X 30W). I took a light reading with my camera and I got 6500 lumens. So why a difference...
It turns out that parallel overdriving does always 4x the power of one ballast -- this is due to the fact that it wasn't engineered or design to operate like this. I measured the power consumed by the ballast through the AC outlet, and it was 80W. So, 80W is actually being delivered to the tubes -- so that means 80W X 86 lumens/watt = 6900 lumens. Okay...close enough.
Here's some more info. I'll try to draw up a schematic and email it/post it (or something a long those lines)
The Measurements:
This is for a 90 gal (48x18x24) tank. It has a 5 inch DSB and the lights are 5 inches from the water. I have two overdrive lamps - two 6500K. I will be adding a third, but it will be actinic.
My lighting measurements are the following :
At the surface, 16000 to 20000 lux.
At middle of tank, 7000 lux.
At bottom of the tank. 4500 lux.
BTW, usually 2x175W MH produce this much light It is also...encroaching the 2x250W area.
Temperature...too hot to touch for more than 5 seconds, but doesn't burn your finger off (say, 50-60 degrees C at the tube). Also, its not hot enough to melt those cheap $3 end caps
Ballast...those ballasts are rated for ~110 watts (i.e. 4X30WX88%) ...don't expect them to get hotter than 40 degrees C.
Those Who Dare to Try:
I would start with 1x drive first and measure the power consumed by the ballast. Then, I would try 2x...then 3x and finally 4x. Since each ballast will be different, results may vary. Personally, I would limit overdriving to 90W or less.
So...there you go. 6000 to 6500 lumens for $40....its being working for me for about 2 to 3 months. So..what do you think...please post your comments. Thanks.
- Victor.