noob resistor question

[dmrabbit]

Hey CPF, I have a question about a project im working on. I have a Dorcy 3aaa light the im putting a SSC p7 bin c LED in. 45 lumen wasn't really cutting it.

I was wondering if I just need to put a resistor in line or do I need an actual driver. Im just looking for basic on/off.

thanks for help or any tips

-dom

 

[lowatts]

Yep I put a megaohm resistor in mine and it worked great :thumbsup:

BTW you'll want to post Qs like this in the G/A/L forum, not the B/S/T unless you looking to sell this beast.

 

[Gunner12]

The AAA batteries have a hard time with a single die high power LED, a Quad die high power LED will kill them, even rechargeables will suffer.

If you do go for the P7, no resistor should be fine. It was designed to take 2.8 amp and even rechargeable AAA batteries sag to 1.1v at those currents(which isn't the right voltage to power the P7 at 2.8 amp).

I'm guessing 1-2 amp to the LED with good rechargeable batteries. That is still a pretty bright floody beam.

I'd suggest just swapping the Luxeon for a Seoul P4 and keeping everything else stock. But if you do go with the P7, I'd like to see some pictures. I haven't seen a P7 powered by AAA batteries yet.

:welcome:

 

[LukeA]

It should work ok. The P7 should handle all the current the AAAs can supply, and do it very efficiently, because of the relatively low current. With no resistor.

Bright and floody.

 

[dmrabbit]

thanks for the help and sorry its not posted in the right section. I was worried that 4.5v to a p7 that handles 3.6/3.7 would kill it sooner than later. If the project works ill send some pics.

 

[Gunner12]

The batteries will quickly sag in voltage due to the high current draw(especially alkaline batteries), so no worries there.

 

[Greg G]

Sounds like a bad combination to me.

What kind of runtime would it have? 10 minutes? If that?

I'd put on of those new U2SWOH Seouls in it.