My lights intensity decrases when adding a fan

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perezbob

Aquarium Advice Apprentice
Joined
Jul 17, 2003
Messages
18
Location
Tampa Florida
I added a small 4" fan to my 2x 96 PC lights and have been noticing a decrease on the intensity of the lights. If I turn the fan off the lights get very hot and if I turn the fan ON the temp goes down as well as the light intensity decreases.

My bulbs are 6 month old running about 7 to 8 hrs daily.

Any ideas on what is happening ?

Thanks
Norberto
 
what voltage is the fan?... is it 12 volt? Also is the fan being powered by the same power strip as the lights?
 
Fans and ballasts

The fan shouldn't blow on the bulbs.. Correct? Just the ballast. I've never encountered the decreasing brightness fenomenon, but, suppose if its the heat that is creating the light, less heat would mean less light.. :)

--Micah
 
Hola!

1. It is a 110V 4 inch fan from Radio Shack.
2. Yes, It is connected to the same strip than the lights.
3. It is blowing both the bulbs and the ballast thru a side opening.

- I'm going try connecting it to another current outlet.

- I'm going to turn it around and use it as a heat extractor instead of blowing directly to the bulbs.

- I'll take some pictures.

Thanks for your inputs,
Norberto
 
the best thing you can have your fans do is always have them on exhaust and not blowing in. also try not to blow on the bulbs because it will hurt the bulbs with the creation of cool spots.
 
Problem solved !!!

The fan is now extracting the heat and plugged to a diferent outlet.

Temperature on the lamps went down considerably.

Thanks for your inputs,
Norberto
 
So your saying that when you turn on the fan you can physiclly see the light output drop?
 
I See FF is a little curious about this, me too.

Bob - Those 4" Pers. Computer type fans draw ridiculously low amounts of current/power (about 10-20watts). It is not logical that the fan's current draw would affect your light output for a few reasons - If both the lights and the fan were plugged into the same outet and that outlet could not provide you with the current you required to continuously run those devices other bigger, badder things would happen, like fuses blowing and wires burin' up. Keep in mind that household outlets typically run between 10-20Amps at 120Volts thats 1200 Watts to 2400 watts. Doubt your 20 watt fan has much impact there. So I think you can plug the fan in anywhere.

Also, Compacts are basically flour. lights and these are not voltage/current dimable, i.e. when the voltage or available current drops below the required level for the balast to keep the ionization of the tube gases from firing then you would likely see other things happen like bulb flicker rather than a consistent dimness. Not 100% sure about this but pretty sure.

I'm confused about this one. Is it possible that you looked at the light with the room lights on differently - for example before installing the fans the room lights were off and the compacts looked brighter, after you installed the fan you looked at the lights with the room lights on (hence the compacts would look dimmer)?


Tom
 
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