What resistor for 2-stage switch for Surefire Classic.

I'm interested in putting the 2-stage switch for the Surefire Classic series on several lights that have been modded with Malkoff dropins.

What I don't understand is the significance of the choices in resistors at the SS. They go from 15 ohm to 60 ohm.

What's the difference?

I'm electrically challenged.

Cameron Reddy

In plain terms the highter the vaule, the lower light output will be. See this thread for lots of info.

http://candlepowerforums.com/vb/show...ighlight=McC2S

pbs, Thanks.

I got through the thread but still could not get a sense for how much of a reduction in light is accomplished by the various choices in resistors, which are 15, 22, 30, and 60 ohms. I presume the 15 ohm resistor would produce two levels fairly close to each other, and the 60 ohm resistor will produce the largest variance in the two levels. Yes?

And a question that arises from the above is, will the run times on low be progressively longer as you increase resistance? This question arises from my understanding that a light engine needs to be designed efficiently for the various levels of light production.

So, in the case of the generic SF light engine or, in my case, a Malkoff dropin, will the low power stage of the switch reduce light output and concomitantly increase run time?

Cameron

You are correct, the 60ohm will provide the greatest variance (i.e., lowest "low") of these.

Regarding runtime, I'm not techical enough to know how resistors affect efficiency but it makes sense that while a resistor is in effect creating resistance, it is also causing the lamp to draw less energy. So I would think it would allow increased runtime on the "low" setting. I'm sure someone more technical can support or correct me!

I had one for my 6p with a Q5 LED drop in. The resistor value was 30ohms, and on the "low" setting it appeared to be about as bright as the incandescent p60 lamp, or 60 lumens. On high it appeared to be full output. Hope this helps.