Hovering inside, rock solid. My app battery settings are 10 percent and 30 percent (IOS .2). When my battery hits 39 percent I get a "Critical" voltage warning and immediate auto landing (very smooth). GPS mode, all pre-flight done, all updates on craft. Any one know what would cause this?

Hummm Not sure, You said GPS mode so did you have GPS Lock while hoovering inside? Well I've set mine to 25 and 35 and have tested it out in 20 degree weather and when it got to around 13% it was wanting to land and was glad that I was close to the ground by that time. I just gave it a little more throttle got it to a spot where I wanted to put it down and all was good. Call me more conservative

Check your battery history and see if they are any errors - it could be that one of the cells in the battery experienced a sharp voltage drop.

A one off may not be too much to worry about but if it keeps happening you might want to consider an RMA on the battery.

pauldean85.emai Posted at 2015-1-25 01:11
Check your battery history and see if they are any errors - it could be that one of the cells in the ...

I just checked my 3 tb47 batteries history. Each had 1 Low Voltage warnings. Could that be from the factory, maybe a test of some sort? No history warnings in the last 10-20 history entries on these batteries.

How many times has this happened? If only one time I would do a few more test hovers and see if it was just a single cell drop. Watch the battery monitor while you are doing the test. If you get 2-3 solid flights without issue, I would assume you are ok.

This is the second different battery this happened but, both times in the house. I did look at the battery monitor both times and all was good (green and even). Could it be something from the IOS (iPad air2?) I have a Nexus 7 coming in on Monday, I'll try it again. Both times it happened exactly when the battery hit 39 percent (2 different batteries).

Possibly but I'm running ios as well and haven't experienced this.

Thanks, I'll run another battery down to this level later and post my results.

I just hovered a battery down past 39 percent without this issue. I don't want to be too picky, just trying to protect my investment. I did notice this battery went from showing 39 percent to 10 percent really fast. I'll wait for my prop locks and fly it like it was designed to be flown!

stevejg16@gmail Posted at 2015-1-25 02:17
Thanks, I'll run another battery down to this level later and post my results.

Try cycling the Battery a few times. What I have noticed with mine is that when I gave it the first charge, both the Controller and Battery (charged one at a time) the Battery and Controller only took a few minutes to come to full charge from 48%. Then when I used both of them I did not get much time out of them at all. I ran both of them down to the point that there was one green LED on the Controller. When I charged them the second time again separately it took 3-4 times the length of time to bring them to a full charge and they both operate the specified time from the spec and then some. So again, try cycling them a few times and do like blade stated and watch the Cells. There is the possibility that a Cell is bad and it should show on the Battery Program. One bad cell will affect all of the cells.

Glad you posted this as I too get a GPS lock signal in doors funny when the app shows the uav in my home and its every move including its rotation etc..
Its smart to hover test each battery !!

A YouTube video on Lipos suggests only taking new batteries down to 50% the first 4-5 times.  This will condition the battery and prepare it for a more "full" use and supposedly increase the battery's lifespan.  It reminds me of the old way of breaking in a new vehicle by limiting speed for the first few hundred miles, so the parts get gently lubed and broken in, and I think it is similar inside the battery cells.