acdii

What should the cutoff voltage be for a plane just before the ESC cuts power? Ihave a battery alarm that will beep when it reaches a set volt, so Ijust need to know what it should be. Ihave it set to 3.2 at this point and Inoticed it beeps rather quickly when the pack gets warm. It was a shorter flight than I thought it would be, so I am thinking Ihad it set too high.

guver

My Feedback: (325)

Since the loaded voltage and resting voltage differential can vary so much it is expressed like this:

It is a cut off voltage that ultimately winds up being a resting voltage of about 3.7 volts per cell. The lvc could vary from 2.5 to 3.5 easily.

acdii

I cant find my book for the ESC so I dont know what the cut off voltage is so I can set the alarm.  The plane is too quiet when a popper is up with it so I can't hear the surging when the limit is reached, but I can hear the beeper.

guver

My Feedback: (325)

How about setting the beeper voltage so that the packs rests at 3.7 volts per cell. If your first try as posted above had a lot of remaining capacity then you can probably go ahead and set it lower than it was.

acdii

I had it set to 3.2 and it went off, when I landed the packs were at 3.8. I may have a pack going under though, I was only up a few minutes when it started beeping, but the pack before it I was up 10 minutes and still had plenty left when I landed.

guver

My Feedback: (325)

In both cases it sounds like you could set it lower. Maybe you used a pack that wasn't charged?

Probably 3 volts is a good setting and should really be thought of a "insurance" in case one forgets to land in the proper timed window. It shouldn't really be thought of as a device to tell one when to stop. I know I'm guilty of it too , I have one plane that I fly on purpose to lvc because I like to maximise the flight time , it is accurate every time and it is an easy plane for me to dead stick it in every time (GP flylite)

You could also be onto something and be right about a pack getting weak,old,damaged, ect. How is the performance of the pack? Is it a lot worse than other packs? If it was indeed full when starting and the timer went off at 2 minutes then compared to your 10 minute pack it is at best a lower quality,damaged,old,worn, or out-of-balance pack.

acdii

What I noticed was this pack was a lot warmer then the first one, and after it sat for a while the voltage was back up to 3.9. I have 3 of the same types, Gen Ace 25c 3300 packs. The one I flew before it was the same type, bought at the same time and flown the same number of times.  Maybe I hot dogged it more than the first one.

guver

My Feedback: (325)

Sounds like it is time to retire it to a less demanding app , or perhaps is best to dispose of it. I have many old used packs that I no longer used have a new lease on life since getting into airplanes. It has allowed me to fly gentle long flights without buying too many packs. I'm happy to put them to good use.