transmitter battery calibration

lostcity · Post by **lostcity** » Mon Nov 24, 2014 10:10 pm

I am using a Turn 9x V2 with ER9X r113. Flashing went well with the Smartie Parts board. Issues with the back lite have been resolved thanks to the forum. I have been flying with this sytem several times now and love how this system works. I have run into an issue that has me confused. My 9X runs on a turnigy LiFe 9.6 battery pack. The low voltage waring goes off at about 9.4 volts. However when I put the battery back on the charger it reads closer to 10.16? Is there a battery calibration function in ER9X? I am not sure it is reading the battery voltage correctly.

Thanks for a great OS

Post by **MikeB** » Mon Nov 24, 2014 10:33 pm

On the DIAGANA menu.
You should find the battery voltage highlighted beside the A8 value. Press menu to get it flashing, then you can adjust the reading with the left and right buttons. The adjustment is finer than the displayed value can display so it may not change with every button press.

Mike.

Post by **jhsa** » Mon Nov 24, 2014 10:38 pm

it's also normal the charger displaying a higher voltage WHEN CHARGING.. You should measure the voltage with a voltmeter with the radio on, and then insert the value you're reading on the DIAGANA screen as Mike explained above. Don't use the charger as a reference.

João

Daedalus66 · Post by **Daedalus66** » Tue Nov 25, 2014 12:07 am

Typical behavior of a 3s LiFe pack is to reach 10.7v or so at the end of charging. When plugged into the transmitter a few minutes later it reads around 10.2v. That drops over a fairly short time to 10.0 and the settles down at 9.9v for several hours, only gradually dropping to 9.6v. After that, it starts to go down increasingly rapidly, so that's where I recharge.

The 9.9v is consistent enough for LiFe batteries that you won't go too far wrong if you use it to calibrate the voltage reading. Just charge the transmitter and run for about an hour. Of course, measurement of battety voltage under load with a good meter is more accurate, but this will do at a pinch.

I set low voltage alarm for 9.3v but always charge before that.

Post by **jhsa** » Tue Nov 25, 2014 12:35 am

I did charge before at 9.3.. Now I charge at 9.4V

Daedalus66 · Post by **Daedalus66** » Tue Nov 25, 2014 1:02 am

Those are perfectly safe alarm values in terms of giving enough time to get the model safely down without rushing. But I want to be sure that when I go out to the field I have plenty of time for flying. Hence 9.6 (or higher) as the charge point.

Sent from my iPhone using Tapatalk

lostcity · Post by **lostcity** » Tue Nov 25, 2014 5:02 am

jhsa wrote:it's also normal the charger displaying a higher voltage WHEN CHARGING.. You should measure the voltage with a voltmeter with the radio on, and then insert the value you're reading on the DIAGANA screen as Mike explained above. Don't use the charger as a reference.

João

Thanks for the replies. All very helpful. Just as a point of discussion, I had assumed that my charger (Accucel 6) was reading pack voltage as it was plugged in. So if my 9X said I was at 9.4 volts, the charger at start should agree or at least be close. I just did not expect to see that much discrepancy. I would also agree that a static measure is apt to be higher than a measure taken while under a load. I will get the multimeter out and see what's up.
Thanks again

lostcity · Post by **lostcity** » Tue Nov 25, 2014 5:30 am

My bad, just updated the firmware to r814 all makes sense now.

lostcity · Post by **lostcity** » Mon Dec 15, 2014 3:58 am

All fixed now.

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