I really appreciate all the help gentleman. Its a good possibility the flight battery is so bad I should look into another one. I am up for a trip to Morganton some time.
A solution for some GPS acquisition troubles
- Thread starter Derrvish
- Start date
Do you have a multimeter so you can measure the voltage of each cell? The attached document will explain how to do that.
I'm getting 3.76 for each cell. Which needs recharging. I have a 2nd battery showing 4.13 for each cell.
How long ago were they charged? Do you use a charger that can put your batteries at storage level?
The one at 4.13V/cell is close to full charge of 4.2V/cell. The thing to remember is that there is only about 0.5V/cell difference between the nominal voltage and full charge voltage. This is the usable range on the battery. The other thing to remember is you are reading an unloaded voltage and as soon as current starts being drawn the voltage will start dropping. As the batteries age the internal resistance rises and the power available to the aircraft is less.
The one at 4.13V/cell is close to full charge of 4.2V/cell. The thing to remember is that there is only about 0.5V/cell difference between the nominal voltage and full charge voltage. This is the usable range on the battery. The other thing to remember is you are reading an unloaded voltage and as soon as current starts being drawn the voltage will start dropping. As the batteries age the internal resistance rises and the power available to the aircraft is less.
It's probably not a good idea to fly more than a couple of feet off the ground. The battery is subject to unexpected failure. Maybe just start the motors and watch the voltage for about a minute or so to see if voltage drops before even attempting a lift off. Right now, you're looking at a new battery. A crash will obviously add expense and nuisance. And you would still need the new battery.
If you see voltage dropping as soon as you lift off, land. GPS will drop out. But I guess you pretty much already know that.
If you see voltage dropping as soon as you lift off, land. GPS will drop out. But I guess you pretty much already know that.
Well put these 2 batteries on the charger and they both show blinking blue led errors. Looks like I am stuck buying one.
Any suggestions on where to buy?
Any suggestions on where to buy?
Check the spring loaded contacts in the charger. Use a blunt pencil to repeatedly push them all the way down and release them about 20 times each. This will help break up film oxidation on them.
Were the voltages fairly even cell to cell on each of the batteries? Were any of the cells below 3.2V on either battery?
I saw those voltages and they seem even on both batteries. The blue light can be caused by too large a voltage difference between cells or if cells are below 3.2V. Since yours don’t fit that scenario there must be poor contact on one or more balance terminals. I will take a charger apart tomorrow and take photos and explain how to check voltages on the back side with a battery inserted. Hopefully we can determine what is jcausing the blue light issue.
Ok I should have suspected the charger in the beginning since I had removed the connector back years ago so that I could make a remote connector using another charger. Anyway one of the batteries is charging now as it should. So I should be able to do another flight to get more data.
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