I was recently handed a malfunctioning DJI Phantom Quadcopter that anytime the owner tried to lift off, it would just flip backward and crash. So, I went about recalibrating, and figuring out how to actually fly a Quadcopter. Anyway, I figured it out1. Anyway, I flew the unit around for a bit, then when the battery got low, the unit landed and showed me it’s wonderful flashing red light.
So, I brought it in, and plugged in the dead battery. As “luck” would have it, though, the place the unit was ordered from sent a free extra battery (RC-2220C3S) made by some other company (WATSON). So, I figured I’d try that. I checked the unit with a multimeter based on lead coloring, and saw it was at 11.2V, which is fine. So, I plugged the battery into the Quad, and was immediately greeted with flames, and a huge amount of “blue” smoke. I quickly unplugged the battery to figure out what the heck went wrong. An XT60 connector is polarized, so there’s no way to plug in backward. But, if you’re eagle-eye’d, you’ll notice the picture for this post, and something I didn’t even think about prior to plugging in the battery. The pos/neg (red/black) are wired backward! So basically 11.1V and all but unlimited amps (Lithium Poly battery) went up the ground plane, and anything that didn’t have polarity protection was fried (or at least the first thing to short was fried).
- The “front” of the Phantom is determined by which end you point “down” during the compass calibration. According to their rather lackluster drawings, the “front” is the battery door side [↩]