Stanfr0

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Re: Assisted control in Velocity Roam
« Reply #30 on: November 25, 2017, 11:46:40 am »
Two things:
#1 and most important, don't fly a 3S lipo  down to 10 volts.  3.5 per cell on the lowest cell is bare minimum and that is only if you have an alarm that reads individual cell voltages, not just total voltage.  If you over discharge a lipo a few times it gets bad, then worse and worse.

#2 is that when a multicopter gets close to "barely able to stay in the air" it does bad things because it cannot stabilize if all motors must run 100% just to stay in the air.

Thanks Cliff,

I appreciate your advice. I do have a balance plug alarm which is set at 3.6v/cell load voltage (first cell to hit 3.6). Off load is about 4.0v. I keep an eye on the voltage monitor on my transmitter which monitors the total cell voltage,this is 10.x as I'm just using it as a guide of the rate of discharge and don't regard it to be accurate. What minimum load voltage/cell do you fly too?

I did some research before setting the alarm but there is alot of conflicting information. I guess its prudent to err on the side of caution.

Thanks again for your help,

Rob

Re: Assisted control in Velocity Roam
« Reply #31 on: November 25, 2017, 05:33:33 pm »
What minimum load voltage/cell do you fly to?

Generally 3.6v alarm under load.

It depends on the battery and load (old battery or high load = more voltage drop with load, so maybe alarm at 3.5v), the time of day (last flight I fly down to storage voltage, other flights I may discharge more) and even whether the battery gives so much flight time that I don't want to squeeze the most out (then it is only down to storage voltage).

Generally after voltage recovery after the flight I like to see at least 3.6v and usually 3.7v

For a very light load like fixed wing FPV cruising locally I may set it higher to 3.7v

Battery specs usually say never go below 3.3v and I take that to mean under load.

ESCs that have Low Voltage Cutoff the highest voltage is usually 3.3v which I consider to be about useless.