Lighting question

[Milan]

Can anyone give me an insight on "overdriving" fluorescent light bulbs term. What does it mean technically and practically?

 

[zacdl]

They are rated for certain wattage for a reason

 

[Jchillin]

Overdriving refers to adding a ballast and connecting several bulbs in a series, "fooling" the ballast into believing that there's only one bulb. By doing this, the ballast forces the maximum capacity of each bulb, the result being that you can increase each bulbs wattage by 1/3 more than it's rating.

There's a couple of links that I'll look for and come back with.

 

[Jchillin]

Here's the link:

http://www.aquariumadvice.com/viewtopic.php?t=53432&start=10

toward the bottom...links provided to other sources of info.

 

[Milan]

Thanks guys. One thing I noticed is that there are 65W compact lamps (Coralife) on the market, but I could not find compact bulbs rated for this wattage (or am I mistaken ...?). They are all 55W. How do they produce 65W out of 55W bulbs? Does this have anything to do with "overdriving"?

 

[Jchillin]

I have yet to personally own a CF but from what I've seen on various lighting suppliers is in fact 65w CF.

Have you actually seen this discrepancy (an "advertised" 65W which is actually 55w)?

I've linked an example of what I've seen (and considering ordering).:

http://www.bigalsonline.com/catalog/product.xml?product_id=29553;category_id=1875

 

[zacdl]

I think it shortens bulb life, no?

 

[Milan]

Jchillin, that's exactly where my confusion comes from. Those bulbs advertised as 65W are actually 55W. It's not readable on Big Al's web picture, but I went to the store and checked it out. It's 55W.

 

[greenmaji]

Overdriving florecents is really to save money thats it.. if you want to get CF and have the funds then I would go with CF.. after looking into overdriving florecents and reading way too much about it.. I ended up tripping over how they make CF fixtures..LOL. Some of the ballasts are the same! They usually overdive 4 foot bulbs by the way.. some of the links are to the series ones but for the most part they are just plain 4 footers.. and to zacdl's questions.. the expected life of the bulb is about a year if its fan cooled if not it can drop by half.. and they are a certain wattage for a reason because of the life hours advertized by the manifacture.. if you got really bright light out of you new fixture you would think there was something wrong with it when the bulb doesnt last as long as GE said it was suppose to..