T5 Ballast Question

[moonpod]

I'm using all MH right now as well with no supplementals.

 

[Boomer]

Scoot

IU just say this thread and didn't read them all but you guys need to look in BF (Ballast Factor) , Here is a short course of not overdriving and increasing the output by raising the BF.

http://www.reeffrontiers.com/forums/showthread.php?t=6677&highlight=overdrive

 

[Scooterman]

Electronic ballast has come a long way, what he is saying is a simple way of getting more out of a NO lamp using a better BF to do it. One things needed to be looked into if actual PAR, & area covered, these are things that can easily be misunderstood. I'm sure when you OD a lamp, it must go crazy as compared to NO.

 

[Boomer]

Never played with OD fluor's Scoot but OD MV, HPS or MH is crazy. But yes, fluor's also have to be to some extent but not as dangerous. That is allot of extra energy driving those filiments and exciting the Hg. I wonder if OD fluor's is enough to drive some of the Ar to ionization. I would automatically assume that PAR and coverage would increase. IHMO there would be shift in K for sure and even more sure of the drop in half-life.

 

[Scooterman]

I wonder if OD fluor's is enough to drive some of the Ar to ionization. I would automatically assume that PAR and coverage would increase. IHMO there would be shift in K for sure and even more sure of the drop in half-life.

Personally OD slightly over I wouldn't see any harm but as these new ways of making these lamps more precisely I would think, you can OD to a limit, I think OD older style lamps were more beneficial because of the design & manufacturing process of the lamps weren't as precise as they are now, more so compared to smaller tube diameter lamps. I would expect the half-life would drastically be reduced & K would go up along with Par & coverage but at an inconsistent rate, maybe to an undesirable range. I don't know what effects this is to Ar, but would be interested in the affects it has on it. From what I've read over RC, IC claims this isn't true, the bulb last just as long, is 30% over driven, it is like no undesirable affect is caused by using their IC660 ballast on T5 H.O. 55w lamps, OD @ 80w. I have No actual data to compare, so all claims that they are really bright, some say equaling lower MH range of PAR are from observation I guess. I admit lighting to this level isn't my forte but I do deal enough with industrial lighting systems to have a little insight of what is going on. Personally for a reef I don't think it is cost effective to try & design a reef tank around this concept, I'd invest in a natural lighting tube from the roof to the tank like sky lights in a kitchen over this practice (ever see those highly reflective tubes about 18" in diameter from the outside roof all the way into the home, lighting up a room very brightly?)!

 

[dnjan]

IHMO there would be shift in K for sure and even more sure of the drop in half-life.

Why would there be a shift in K from overdriving? I thought the spectrum from flourescent bulbs was dependent upon the phosphors, and increased brightness just came from making the phosphors flouresce more often? Or would the overdriving affect different phosphors differently (some flouresce more often than others)?

 

[jlehigh]

I think often times we mistake brightness&intencity for a color shift. IME the brighter the bulb the lighter (whiter) the Kelvin appears, but does not mean the spectrum is indeed different.

 

[Boomer]

Many things can cause a K shift. An important factor is internal bulb pressure and temperature. The pressure and heat are both a function of the rise in Ar (Argon ) gas pressure and Hg (Mercury) vapor pressure. OD a lamp can make both of these rise. Increased bulb pressure increases output and makes the lamp produce more lumens / watt. Ar, in a fluor lamps, does not add light as it does in a MV, MH or HPS. It purpose is to make the lamp have more output with less wattage. Fluor's are LID (Low Intensity Discharge) Lamps and do not produce enough energy to ionize the Argon gas. If it did, it would change the K value, as the Ar is producing visible light. Almost all the light in a fluor produced is UV, where its wavelength is lengthened by the phosphors.

OD can cause a deterioration of the phosphor coating. The filaments also break down more quickly and leave a emissive material on the inner surface of the bulb. Both of these will cause a shift in K and light output. You guys need to remember that light bulb data is based on std tests. For example, x type HO lamp running at an ambient room temp of 60 F will produce 100 % output. Taking that same lamp and increasing it to 80 F will reduce the output to almost 90 %. HO's actual produce more light at lower ambient room temp than NO's. It takes more UV energy to drive some phosphors than others, where other phosphors require less UV energy. This shift in temp or pressure changes the energy output of mercury. This and the above change the output and K.