RC Battery question/concern

[MurMan]

Morning group....I'm fairly new with 70 ish flights and 69,000 meters so far, in one month.
At first, I could safely get 3 flight batteries from one RC charge. Now two is the norm..perhaps more intricate flights?
The issue I experienced today is perplexing. I fully charged the RC and put it away in the bag two days ago. When I connected this am it showed 55%. I started the MP and noticed level dropped to 45%. I was also getting a Restricted Zone warning and I couldn't get around (6 km from a small airport). Since I wanted only a few low level pictures I thought I'd accept the Terms and C..but couldn't get to a screen to accept.. (seperate issue)...so, I charged the battery to 55% and took off. Within maybe 5 min I noticed RC battery at 13%. ! I did a RTH at 40 M, it returned...almost, voltage dropped to 6%, I got it down enough to pluck it and within seconds I was at 1% then the RC shutdown.
I came home and it showed 0%...I grabbed my phone to take a screen picture of that and when I pressed the battery check again it showed 71%. . Waited 2 min and checked again...70%. About where I would expect it to be...
Any ideas or similiar experiences?

 

[Saj]

I would contact DJI clearly something going wrong, not read of hear of this before.

I find mine to be approx 55% after using all three batteries.

 

[MurMan]

I would contact DJI clearly something going wrong, not read of hear of this before.

I find mine to be approx 55% after using all three batteries.

Thanks....I wish! I have never had that much left after two batteries... I am going to fly it again now and see what happens..

 

[MurMan]

Thanks....I wish! I have never had that much left after two batteries... I am going to fly it again now and see what happens..

This flight was fine. I started with a 72% MP battery to run it down and a 100% RC battery. My S7 Galaxy had 60 % or so and it flew 16 minutes and I had 72% RC left.
However, I just realized tonight after doing more reading that the RC appears to be always charging my S7, contributing to lower RC reserve and a much warmer S7!
I left it connected and reviewed the flight and RC dropped to 58%.. a quite severe drop and the phone was quite warm, borderline hot. Is there a way to set the phone or RC so that it doesn't try and charge the. S7?

 

[enohp15]

Use the other port on the controller. That will stop the charging issue I believe.

 

[AnzacJack]

yep, i always use the lower port so as to not be dragging charge from the controller.

 

[MurMan]

yep, i always use the lower port so as to not be dragging charge from the controller.

Great...thanks for the tip! How do you secure your phone or are you using another configuration?

 

[GerdS]

Great...thanks for the tip! How do you secure your phone or are you using another configuration?

Nonsense, Android phones/tablets will always get charged, no difference which port they are connected to.
The only method to prevent this is rooting the device and disabling charging by a special app. Would not recommend it.

 

[AnzacJack]

Nonsense, Android phones/tablets will always get charged, no difference which port they are connected to.
The only method to prevent this is rooting the device and disabling charging by a special app. Would not recommend it.

really?
i know that my ipad doesnt draw a charge using the center plug, i just assumed that android would be the same

 

[GerdS]

iPones don't charge with the DJI standard cable supplied for the side port because of their Lightning interface and converter built into the cable.

 

[MurMan]

OK, well now that we know Android and Apple have different charging parameters, at least I know where I stand, I find there are lots of "little things" like this that are not covered in the literature. That would be another, if not the chief reason, you are encouraged to start out with a fully charged phone. I did do that but got lax when I realized the phone would last more than long enough to fly three batteries. That would also explain whey RC battery times seem to slip over the month...it was always charging a 50% phone. On the Bright Side.. I Love this Little Machine!! Thanks everybody for the input.

 

[MurMan]

One more comment and question... bear with me. I did try the cable to the bottom USB port and it doesn't charge.....until you turn the controller on.. So proving GerdS's statement. Pity it does that.

Back to a more important matter..My first post was primarily about a wildly discharging RC battery on Aug 1. A flight the next day was OK...as was the first one today checking out the Enhanced Warning Zone problem (see another post I made earlier in another section). On the second flight, I experienced a rapid discharging RC battery and conversely a rapidly heating S7 phone. I landed it with about 3% power level showing and Low Battery warning message and by the time I picked the Mavic up it was at 1% and the controller shut down within seconds. I disconnected my hot phone and put the controller down and when I pressed the battery check on the RC about 30 seconds later it showed 72% !! I took it home, and let it sit on the bench for at least an hour and now it indicates 82%. Where it should be for a 17 minute flight.

I have come to the conclusion that the phone, on a bright sunny day, in auto brightness mode, runs the screen at 100&% brightness and sucks the power from the RC, but there is NO WAY that should drop to 0 and then shut down and then turn around and indicate over 70% almost immediately... The next flight will NOT be with auto brightness enabled and I shall see what happens.

I am open to ideas and suggestions!

 

[Xanthus]

One more comment and question... bear with me. I did try the cable to the bottom USB port and it doesn't charge.....until you turn the controller on.. So proving GerdS's statement. Pity it does that.

Back to a more important matter..My first post was primarily about a wildly discharging RC battery on Aug 1. A flight the next day was OK...as was the first one today checking out the Enhanced Warning Zone problem (see another post I made earlier in another section). On the second flight, I experienced a rapid discharging RC battery and conversely a rapidly heating S7 phone. I landed it with about 3% power level showing and Low Battery warning message and by the time I picked the Mavic up it was at 1% and the controller shut down within seconds. I disconnected my hot phone and put the controller down and when I pressed the battery check on the RC about 30 seconds later it showed 72% !! I took it home, and let it sit on the bench for at least an hour and now it indicates 82%. Where it should be for a 17 minute flight.

I have come to the conclusion that the phone, on a bright sunny day, in auto brightness mode, runs the screen at 100&% brightness and sucks the power from the RC, but there is NO WAY that should drop to 0 and then shut down and then turn around and indicate over 70% almost immediately... The next flight will NOT be with auto brightness enabled and I shall see what happens.

I am open to ideas and suggestions!

Hey, I just got a mavic and I had a very similar experience to yours with the s7. Have you found a solution?

 

[MurMan]

Hey, I just got a mavic and I had a very similar experience to yours with the s7. Have you found a solution?

I have only flown once since, and I did so with auto brightness turned off and I didn't have any issues. So, I suspect that is the culprit, placing a heavy drain on the RC battery. Maybe a sun shade for the phone would be a good accessory. If I have a reoccurance, I'll post again. Good luck!

 

[MurMan]

Well we all have good intentions... I decided to fly a short flight to run down a MP battery at 72%, and what should have been a full charge on the RC showed 58%. Since I was flying close to the take off point, I decided to go ahead. Flight was approaching 7 min and RC battery was depleting quickly. I landed with about 5 % on RC and I unplugged the phone and cord and it fell to 0% and RC shut off. Sure enough, the S7 was still in Auto Brightness mode as I had forgotten to turn that off. After several minutes, I checked the controller and it was back to 72%. I turned off the Auto Brightness and did two more flights, a 6 and a 3 min and the RC unit only dropped to 58%. So, all still points to the S7 putting an excess load on the RC battery which it can't handle. It recovers quickly but that will be of little solace if it fails at an inopportune time. I think I'll write to DJI and see if this is a known issue.
Anyone else experiencing this??

 

[GerdS]

That's not normal, as to my knowledge the output current of the remotes' USB port is limited to 500mA.
But I made the experience that the capacity percentage display on the remote is not linear, means as soon as the capacity drops below 50% it falls much more fast than while above 50%. And if below 30% you can see the falling speed even more and more increasing...

 

[MurMan]

That's not normal, as to my knowledge the output current of the remotes' USB port is limited to 500mA.
But I made the experience that the capacity percentage display on the remote is not linear, means as soon as the capacity drops below 50% it falls much more fast than while above 50%. And if below 30% you can see the falling speed even more and more increasing...

Yes, once you get, like you say below 30% or so, it drops like a stone. I am using the small port (micro usb) on the side. Perhaps I should try the bottom USB port. The real issue is not so much whether the display is accurate, but that is gives a low battery warning and shuts off (which causes heart palpations), and then soon afterwards, shows the correct (or higher) percentage and flies just fine. As Spock would say, it' not logical!

 

[Xanthus]

Yes, once you get, like you say below 30% or so, it drops like a stone. I am using the small port (micro usb) on the side. Perhaps I should try the bottom USB port. The real issue is not so much whether the display is accurate, but that is gives a low battery warning and shuts off (which causes heart palpations), and then soon afterwards, shows the correct (or higher) percentage and flies just fine. As Spock would say, it' not logical!

Could you please try to turn on the controller by itself without connecting a phone to it or turning on the drone (just let it idle where it says "connecting") and see how long it takes for it to drop 1% battery? I timed mine and it drops 1% every 74 seconds or so, which seems a lot quicker than it should be...

 

[MurMan]

I have turned the screen brightness down and that seems to have cured the issue as it has only happened once since. I let it hover near me and watched as the RC dropped to Zero and after a few minutes it showed 74% and I reconnected at all went well, as the drone continued to hover.
I didn't have a chance, when I remembered the request to experiment with a discharge rate per hour. Will do WHEN I remember.
DJI said I could send it back for testing but neglected to say where it had to go (I'm in Canada), or provide an estimate or any guarantee of a fix or replacement, or time frame.

 

[Haloweenhamster]

Get a portable phone charger
I have my phone plugged into the bottom port and battery plugged into the side port, RC doesn't leave 100% neither does the phone