rtparty
Raise The Reef!
Thanks for your reply.
In my previous reply I stated that the Sunpower and Power module differed when it comes the the amount of fans and the separation of air chambers to cool the bulbs. (powermodule seperates per two bulbs, Sunpower not).
A local hobbyist opened his 39 watt Sunpower pendant to change the ballasts for dimmable, and found 54 Watt Ballasts. I assumed this was the case with all the pendants, but maybe this was a fault with assembling by ATI. I haven't opened my own pendant yet.
Maybe the older models were overdriven and the recent models aren't?
I think because of the longer way the air travels with longer bulbs then the 24 watters, the fan speed have to be higher to prevent the overall temperature to rise above 95 F.
Not only the temperature at the caps is important, but also around the whole bulb.
Some posts claiming the overdriving bulbs aren't a problem as long as you don't let the bulbs overheat. (+95F) This overheating will burn the phosphors faster and reduce the lifespan. I will search for them again.
What is you experience with this? Does it work this simple or is cooling just a part of the problem with overdriving and reduced lifespan?
I'm not trying to be smart, but enjoying an informative discussion that allow us to light our reefs better
Leonardo
I think I misunderstood your cooling statement. For some reason I read it that they used different cooling methods. My bad.
From everything I have read and seen ATI doesn't overdrive their bulbs. I know you can buy ballasts that will power 24 and 39 watt bulbs. Like you said in your last post, the ballast knows which to run it at.
I love informative discussions where many contribute and we all learn for the better. Sonny's build thread is a GREAT example of that. Many have switched to T5 because of his success!
If you find kangym's thread about PAR readings and changing bulbs, you will see that a few of us in there discussed the different fan speeds in relation to bulb length and surrounding air temperature. I found that on my 24w Sunpower that there was only a 1 degree difference between running the fan at 7.5v and 9v. I chose 7.5v for the silence it offered compared to 9v. However my lights are on during the day so noise isn't a big deal to me.
As far as cooling goes, over driving bulbs will always shorten their lifespan no matter what temperature you cool the bulb to. At least to my knowledge. It just has to do with pushing something harder than it is meant to be pushed. Go drive your car in 2nd or 3rd gear all the time. I would think that the engine or transmission would not last as long compared to those who drove their car in the proper fashion.
I myself am not a fan of overdriving bulbs. The PAR gain is minimal and the damage is high. More heat, less life for a few percentage gain in PAR.
Anyways I went way off topic. Sorry Sonny! :spin1:
