led replacement bulb question?

[coachbigdog]

Ok,this may be a stupid question for those who know,but I DON'T know.If a replacement bulb like the epieon is used where it comes in 3 different volts,is the brightness effected by the # of cells? I know that if I put a 2 cell bulb in a 3 cell light it will be brighter if not burn it out.But what I mean is if you took the 2 cell bulb and put it in a 2 cell light,would the brightness be the same if I took the same light(host) but put in the 3cell bulb? Or would the 3 cell bulb in the 2 cell light actually be dimmer? I know what I'm trying to say,but not sure it's coming out right.Hope someone can understand my "thoughts".

 

[eebowler]

I believe that most of the unregulated LED replacement bulbs out there that are designed for 3 or more cells, simply have a resistor inside of the bulb base. I therefore assume that a bulb made for 3 cells will not work well at all with two cells. Two cell LED bulbs I am sure, have some sort of step up circuits in them.

Does this help?

 

[kongfuchicken]

The brightness will definitively be affected by the # of cells. Underdriving one of these shouldn't be a problem but I wouldn't be confortable with overdriving because of the less than perfect thermal relief the small PR base has to offer.
Now, I guess they made different models for a reason... /ubbthreads/images/graemlins/icon3.gif

 

[nikon]

The 3 cell bulb in a 2 cell light would be dimmer. The 2 cell bulb has a boost circuit which the 3 cell bulb doesn't have.

 

[coachbigdog]

Ok,thanks!

 

[14C]

coachbigdog, if you want an LED for a two cell light you will be best off with the EverLED I think. I have a white one and have used it in a 3D mag and it's now in a plastic 2D emergency light hanging in my closet. It's expensive as compared to other offerings but I know it will work when I need it and it has a nice output even on two cells. FYI, I have not tried the Diamond Replacemet in a two cell light because the shield/heatsink prevents it dropping in to most.

 

[TrueBlue]

Coach...I have an EverLED you can buy! /ubbthreads/images/graemlins/crackup.gif

Sorry, inside joke. (I just bought an EverLED from Coach.)

Nothing to see here; move along.

 

[Steelwolf]

Do not attempt to overdrive the Epieon LED replacement bulbs. Or go ahead and overdrive them, understanding that because of the horrible heat transfer of the PR bulb base, your LED will be running much hotter than designed. And that can mean thermal runaway, a blown bulb, and you out by $xx.

AFAIK, the Epieon does not have any circuitry inside it except for a resistor for the bulbs meant for more than 3 cells. The 2 cell bulbs are picked for low Vf so that it will work in 2 cell situations.

I suppose you could run the bulb on more cells if you figure a way to improve heat transfer from the bulb base to the exterior of the flashlight.