I have a 3s pack that I wanted to re-purpose for bike lighting. Does anyone have experience or comments on running a Yinding or the Nightfighter BT-21 with a 3S battery pack. I am assuming there is a buck driver in the light but I don’t know enough to tell if it will handle the higher voltage coming from a 3S pack.
If it is possible to do this, how much power is being wasted by the buck driver when such a high voltage is fed into the driver?
I can't speak to your specific lights, but I haven't met a 2S buck light that can't take 3S and even 4S. Efficiency should not decrease much. Might even increase as bucks run best with some voltage overhead. If your emitters are also 2S, you have very little voltage overhead.
Both lights have two emitters that output the same light level at each setting. As I don’t know much about the diver circuitry I don’t know if they are driven in parallel or in series? The emitters are XM-L in the Yinding and XM-L2 in the Nitefighter. Does this info suggest whether the emitters are “also 2S”
I’m really reluctant to let the magic smoke out so if anyone with knowledge of the drivers in these lights or experience using a 3S pack could chime in and confirm 4Wheels’ thoughts, I’d be grateful.
S.
I’ve tried using my BTU Shocker’s 3S1P battery pack on the Bike Light I won from Ledoman. The light however is different because it is already modified, has 6 emitters and does 40 watts at high.
Currently I’m using it as a handheld searchlight for my car (since its too bright for my bike) and I am using the cigarette lighter jack as power source. It also does 45 watts.
If you have the lights open, post a couple pics of the drivers and emitters (with reflectors and isolation rings off so MCPCB traces are visible). That may enable those familiar with electronics, but not your specific lights, to be able to advise you. It they are buck drivers and have a 6 pin component marked "LEDAxxx", they should be fine with 3S cells. That component is one of the most popular buck converters used in Chinese drivers.