Sofirn SD01 tail Amp woes

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Sidney Stratton
Sidney Stratton's picture
Last seen: 4 hours 45 min ago
Joined: 01/28/2018 - 22:59
Posts: 615
Location: Canada
Sofirn SD01 tail Amp woes

For the likes of me, I can’t get my Sofirn SD01 to turn on via my power supply nor an out-of-the-case battery.

I wanted to get some tail amp readings and all manner I tried to devise a secondary power input, the light just doesn’t work. I’ve tried with my homebuilt power supply, set at 4 volts and the current reading is about 5.6 Amps, no light. The voltage fluctuates between 3.56 and 3.88 Volts. The supply can deliver 40+ Amps when pushed.
Then tried a 26650 cell with the same readings. Again no light. Also tried with 4 × 18650 (parallel) – no go.

Naturally, I cleaned all contacts and checked that there is an electrical path.

Magnetic ring (HAL effect transistors), I have no third hand to start from OFF and click to the various levels, so I just left on Max. Unscrewing the battery case a turn, clicking the ring a few notches, and re-screwing the case, the light turns ON. So no stand-by mode is required to pre-drive the MCU and HALs.

My set-up:

The light in question:

I’d have to make a video to better see the fluctuation of the Volts, but it may not be needed as someone hopefully will explain what I’m doing wrong.

SammysHP's picture
Last seen: 46 min 43 sec ago
Joined: 06/25/2019 - 14:35
Posts: 956
Location: Germany

Does it still work if you use it normally?

the4ds9's picture
Last seen: 10 hours 35 min ago
Joined: 10/28/2017 - 17:06
Posts: 197

I am impressed by this torch. The independent reflectors negates any petal effect that can be annoying. The tint is pinkish neutral white. The reach is good. I notice that indoors and outdoors use of torches differ. Indoors, you don’t need a lot of lumens, and on high or turbo even the 1000 lumens Sofirn lights seem impressive. Once outside, though, the highest mode of say, Sofirn SF36W becomes merely adequate. That is why I like the Sofirn SD01. It has lots of lumens and good reach powered by 4 – 18650’s and outdoors it’s just perfect. Good runtimes!