Customized Surefire MN03 Bulb Burns Out from Surges

Probem: Customized Surefire application using MN03 bulb powered by 6VDC 1400mA power supply burns out from power surge.

Anyone have any ideas for a protection circuit that could be used to prevent surges from causing the bulb to burn out?

e.g.: a resistor in the circuit to DIM the light or a fast-burning fuse?

I tried a rheostat in parallel with the bulb. Rotating the rheostat caused the metered output voltage to drop, but the bulb would not even illuminate when the rheostat was at maximum "open-least resistance".

not up to mu league, but I believe that someone suggest a pack of NTC resistors of very low value...it is a resistor that allows current to flow only once it gets warm...

If we could talk AW into producing a SF E series soft start switch like his C series model, that would do the trick. I think that your fix, for now, is to use the LumensFactory lamps for your E2. They are very hardy, and should not instaflash due to turn on inrush current.

Bill

You are overdriving the bulb.
Bulb is meant to be used with 2 Primary CR123 which nominal voltage is 3V but voltage sags due to battery internal resistance at MN03 1.1A current.
If you are driving MN03 bulb from powersupply I would start at around 5V, not 6V.

Juha

Whoops, I missed that it was being driven off of a power supply. Yes, the MN03 would be, at the most, a 5 volt lamp. Can not overdrive it, as it is on the edge already, probably a 20 hour bulb. Look at common mag bulbs and the voltage rating for them is always lower than the cell requirement to run them at spec.

Bill