Over the past few days I EDC'ed a Dereelight CH2. It has the warm 5A Q3 emitter, 4SD ramp-up driver, and battery voltage protection disabled.
The light is specified at four levels, 1%, 5%, 30%, 100% (low, medium, high, burst)
At the high level and the smooth reflector, the throw is amazing for this size light. The light does get warm, so I use it for only a couple minutes at a time.
Therefore, I kept it at the 30% level. Even so, the flashlight would get very warm.
Then I tried running it at 5% output. Still, the light would get warmer than one would expect.
I ran the light with both rechargeables and primaries.
So I got out two DMM's and simultaneously measured voltage and current, without the tailswitch. With a recently charged RCR (Powerizer 650mAh 3.6V), the levels were spaced pretty well. However, I was measuring as high as 7.4W consumption from the cell on burst!
Now with a CR primary (Tenergy), I was getting almost exact same current and voltage measurements for high and burst. I had to repeat them several times to prove it to myself. You could see the light getting brighter on high, but it was using the same power from the battery (about 3 W).
I couldn't stand to not find out more. So I got out my hp E3633A regulated DC power supply, set the overcurrent protection at 3A (it didn't trip), and the voltage to the range I was seeing from the cells under load. The power supply reads out the voltage and current digitally and simultaneously. I applied the power, waited a couple seconds, and jotted down the readings. I did the measurements spaced out enough the light hardly got warm.
Now I didn't see the 7.4W power consumption again. Perhaps I missed the peak since I was moving in 0.1V increments. Or, since the cell was rapidly discharging I may have missed the effect of decreasing voltage, since I was running constant voltage.
Unfortunately, I don't have an accurate box to measure light output, so I can't track how much light was being produced. I am bypassing the switch by doing these measurements without the tailcap. There is about 0.1-0.2 ohms of resistance there.
The data is below. The first plot is Power, the second Voltage.
The results make me wonder if it's "safe" to run primaries on burst, or IMR batteries on burst, since these would go into the high power consumption region on either side of the graph. 5-7W seems like an awful lot of power.
Any thoughts?
The light is specified at four levels, 1%, 5%, 30%, 100% (low, medium, high, burst)
At the high level and the smooth reflector, the throw is amazing for this size light. The light does get warm, so I use it for only a couple minutes at a time.
Therefore, I kept it at the 30% level. Even so, the flashlight would get very warm.
Then I tried running it at 5% output. Still, the light would get warmer than one would expect.
I ran the light with both rechargeables and primaries.
So I got out two DMM's and simultaneously measured voltage and current, without the tailswitch. With a recently charged RCR (Powerizer 650mAh 3.6V), the levels were spaced pretty well. However, I was measuring as high as 7.4W consumption from the cell on burst!
Now with a CR primary (Tenergy), I was getting almost exact same current and voltage measurements for high and burst. I had to repeat them several times to prove it to myself. You could see the light getting brighter on high, but it was using the same power from the battery (about 3 W).
I couldn't stand to not find out more. So I got out my hp E3633A regulated DC power supply, set the overcurrent protection at 3A (it didn't trip), and the voltage to the range I was seeing from the cells under load. The power supply reads out the voltage and current digitally and simultaneously. I applied the power, waited a couple seconds, and jotted down the readings. I did the measurements spaced out enough the light hardly got warm.
Now I didn't see the 7.4W power consumption again. Perhaps I missed the peak since I was moving in 0.1V increments. Or, since the cell was rapidly discharging I may have missed the effect of decreasing voltage, since I was running constant voltage.
Unfortunately, I don't have an accurate box to measure light output, so I can't track how much light was being produced. I am bypassing the switch by doing these measurements without the tailcap. There is about 0.1-0.2 ohms of resistance there.
The data is below. The first plot is Power, the second Voltage.
The results make me wonder if it's "safe" to run primaries on burst, or IMR batteries on burst, since these would go into the high power consumption region on either side of the graph. 5-7W seems like an awful lot of power.
Any thoughts?
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