Takeoff photo of a nice flight

30mn flight time with a bit of ridge lift - Full reflex wing - 4 Bonka packs - Begin at about 4.15V and drained the batts to zero %. Was having too much of a great time and did not pay attention to my screen😲 .
I thought for sure I had killed them but after the first round of charging they went up to 3.8V and the chargers said “Charge complete” - I became a bit worried. I waited about thirty minutes and hooked them up again. On the second charge they went up quite fast to 4V :grinning:. Waited again, and on the third charge which did not take long at all, they were back on track and averaged 4.18V​:smile: Good enough in my book and ready to go at it again…


Hi Voltair,

To be sure that I never go to deep with my batteries, I bought 4 battery monitors from HobbyKing. They are only $3 each. They are connected to the balancing cable, and held in position by the Velcro which holds the battery.
It looks like a Christmas tree; each monitor continuously loops through the individual cells, displaying first the cell number and then the voltage in hundreds of Volts. But actually I like it because you can quickly see if all 24 cells are more or less full at the same level. No sick one (I Always charge balanced).
And after you landed, you can quickly check again whether all batteries/cells came down equallly.
I fly with two Bonkas on my left main switch to the left motors, and two Bonkas on my right main switch to the right motors plus logic. Works perfect. No difference between left and right. And only half the current and so a quarter of the resistance losses (and heat build up).

By default each monitor starts beeping loudly when one of his cells reaches 3,3V. You hear that clearly above your propellors. Even though they are behind your back. You can set the trigger voltage anywhere between 2,7 and 3,8V. But I am happy with the 3,3V.

Works great for $12 total :grinning:

HobbyKing™ Lipo Voltage Checker


Nice setup! I actually was also using those alarms but do not bother anymore. I am pretty much dialed in with the throttle screen even if kind of all over the place. It was my mistake for having too much fun😄

You should probably use those alarms for your next flight. You might lose voltage fast on individual cells. Are they puffy at all? The fact that they recovered doesn’t mean they aren’t damaged.

The problem with those alarms is you can’t hear them over prop noise. Batch 4 has a vibrator in the controller that vibes when you arm or disarm. We need to program it to vibrate when you hit the minimum voltage.

The batch 4 BMS isn’t available yet but that should monitor individual cells which would be ideal. Couple that with a low voltage alarm vibration and you won’t make that mistake again.

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That would be the best solution you are right

I really hear them very well. And I am wearing a full helmet.