<50% batt life to 3% instantly experiment

[Shazbot4]

And that my friend is the basis of the declaration of independence, the right to freedom of speech and the ability of humans to form their own opinions. There will always be people that agree with you and those who don't. I understand the battery limitations on my machine and how it will react when I get to a set %. Fly your machine how you see fit and if you really think it's an issue then by all means put your opinion to DJI. If you still can't find joy in your I1 then I think maybe is is time to put it on the market and find another hobby.

so lets try this again. you own a battery. your responsible, you fly at 100% every time and land at 30%. no where does dji say this is how to use batteries but you found out somehow and in your mind this is correct and no where does it say automatic landing at 10% when you get your inspire for the first time. so at any time for circumstances unknown it could drop to 3% instantly. dji has programmed the aircraft fly to the home point and land safely when the battery read out goes from 11 to 10%. when it skips past this and goes to 3% this screws the system up and shuts down only the props. or in my case from 11 to 10% it just shuts down the props and falls out of the sky from 1 foot off the ground. sure you can play with the gibal for 30 minuets, record and still receive data but that doesn't matter, it wont fly.

im advocating DJI needs to remove this 10% fail safe feature. it causes more problems then it prevents. if it were set to 1 or 1.5% then it allows the system more flexibility to glitch out and not cause a crash. believe me when they see 50 to 3% they want that inspire on the ground yesterday.

you guys are pointing your fingers at these people who dont fly every time with a battery at 100% like they are being irresponsible and deserve what they got, a crashed inspire, and take joy at their misfortune. there is no where when they unbox their inspire for the first time does it say start flying at 100% battery life every time or there is a likely hood of instant motor shutdown. Thats DJI's fault.

you guys think it's fine then just wait till one of these falls out of the sky randomly, like they are doing now, a lot, and it hits someone or something that makes the news. the inspire isn't for flying at a r/c field in wide open fields with no one around. it's a filming platform for flying in areas with lots of people and things going on and anyone can buy it.

i would prefer us and dji do everything possible to keep these things in the air as much as possible. the only reason these things crash is software, i don't think there is 1 record of mechanical failure on a inspire yet, but there is a lot of room for software problems.

if it's the software that causes the thing to stop flying randomly then it needs to be changed PDQ

 

[The Editor]

so lets try this again. you own a battery. your responsible, you fly at 100% every time and land at 30%. no where does dji say this is how to use batteries but you found out somehow and in your mind this is correct and no where does it say automatic landing at 10% when you get your inspire for the first time. so at any time for circumstances unknown it could drop to 3% instantly. dji has programmed the aircraft fly to the home point and land safely when the battery read out goes from 11 to 10%. when it skips past this and goes to 3% this screws the system up and shuts down only the props. or in my case from 11 to 10% it just shuts down the props and falls out of the sky from 1 foot off the ground. sure you can play with the gibal for 30 minuets, record and still receive data but that doesn't matter, it wont fly.

im advocating DJI needs to remove this 10% fail safe feature. it causes more problems then it prevents. if it were set to 1 or 1.5% then it allows the system more flexibility to glitch out and not cause a crash. believe me when they see 50 to 3% they want that inspire on the ground yesterday.

you guys are pointing your fingers at these people who dont fly every time with a battery at 100% like they are being irresponsible and deserve what they got, a crashed inspire, and take joy at their misfortune. there is no where when they unbox their inspire for the first time does it say start flying at 100% battery life every time or there is a likely hood of instant motor shutdown. Thats DJI's fault.

you guys think it's fine then just wait till one of these falls out of the sky randomly, like they are doing now, a lot, and it hits someone or something that makes the news. the inspire isn't for flying at a r/c field in wide open fields with no one around. it's a filming platform for flying in areas with lots of people and things going on and anyone can buy it.

i would prefer us and dji do everything possible to keep these things in the air as much as possible. the only reason these things crash is software, i don't think there is 1 record of mechanical failure on a inspire yet, but there is a lot of room for software problems.

if it's the software that causes the thing to stop flying randomly then it needs to be changed PDQ

Page 49 of the user manual, item 1 (emphasis added) .:

Preflight Checklist

1.Remote controller, aircraft battery, and mobile device are fully charged.
2.Propellers are mounted correctly and firmly.
3.Micro-SD card has been inserted if necessary.
4.Gimbal is functioning as normal.
5.Motors can start and are functioning as normal.
6.DJI Pilot app connected to the aircraft.

 

[Mark Krieger]

Page 49 of the user manual, item 1 (emphasis added) .:

Preflight Checklist

1.Remote controller, aircraft battery, and mobile device are fully charged.
2.Propellers are mounted correctly and firmly.
3.Micro-SD card has been inserted if necessary.
4.Gimbal is functioning as normal.
5.Motors can start and are functioning as normal.
6.DJI Pilot app connected to the aircraft.

Okay, understood - but after months of these things being in the air, why are we just now seeing this behavior occur?

 

[Kilrah]

no where does dji say this is how to use batteries but you found out somehow and in your mind this is correct and no where does it say automatic landing at 10% when you get your inspire for the first time.

It's fully described in the manual, page 14. No excuse. Just like the manual tells you to fully charge batteries before use and to calibrate them every 10-20 flights.

so at any time for circumstances unknown it could drop to 3% instantly. dji has programmed the aircraft fly to the home point and land safely when the battery read out goes from 11 to 10%. when it skips past this and goes to 3% this screws the system up and shuts down only the props.

Again THIS IS NOT CORRECT. When the battery level goes below 10% it lands, that's it. It does NOT shutdown.

there is no where when they unbox their inspire for the first time does it say start flying at 100% battery life every time or there is a likely hood of instant motor shutdown.

No, because there is no established and direct relation between "not fully charged battery" and "certain failure". It's more like "experience has shown that if you don't have a fully charged battery there's a highly remote chance that a fault could happen, but that chance is slightly higher than if the battery is fully charged", hence the recommendations you find on forums.
And it's just down to "things not being perfect", it's a fault that pretty much nothing could prevent with current technology. Manual battery handling that was on pretty much all multicopters before the smart-battery equipped DJI models was actually much more prone to errors, but that gets (too) quicky forgotten.

 

[Eduardo]

Page 49 of the user manual, item 1 (emphasis added) .:

Preflight Checklist

1.Remote controller, aircraft battery, and mobile device are fully charged.
2.Propellers are mounted correctly and firmly.
3.Micro-SD card has been inserted if necessary.
4.Gimbal is functioning as normal.
5.Motors can start and are functioning as normal.
6.DJI Pilot app connected to the aircraft.

Would the 'Preflight' mean first take off once the battery is turned on?

Suppose I have 2 subjects to film, take off, shoot the first one and 5 minutes later come for landing to take a breath and mentally review the next shot.

Will I need another fresh battery to be safe against the sudden drop mentioned by others? Or only if the battery is turned off before next take off?

 

[Kilrah]

Okay, understood - but after months of these things being in the air, why are we just now seeing this behavior occur?

I've been on this forum since I got my Inspire in January and have seen such reports from day one, with rather constant frequency. Nothing new.

 

[The Editor]

Okay, understood - but after months of these things being in the air, why are we just now seeing this behavior occur?

More of them out there I guess and more people flying them without previous RC experience - also packs are getting older and have more flight hours/discharge cycles on them now. Their internal resistance is increasing (that's a fact of life) and although DJI 'smart monitoring' is supposed to take care of things people are still pushing these things to beyond what you would normally expect a lipo to perform. When a pack is brand new and you abuse it a few times it will behave itself. as they age they are far more less forgiving of bad handling and maybe a few more are coming back and biting people?

1. Always start your flights with a fully charged battery
2. Do not fly your packs below 20% (and certainly NEVER anywhere near 10%)
3. Monitor your individual cell voltages 2 or three times throughout a flight (under load) to ensure they are tracking uniformly - if they are not...LAND
4. Regularly calibrate your packs as per DJI instructions
5. Never store them fully charged (for more than a few days)
6. Never store them depleted (Ever)
7. Allow the packs to cool to ambient temp before recharging or bringing up to storage level
8. Store packs at 50% charge or around 3.85v per cell.

@Shazbot4 - I notice you have posted a thread over on the DJI forum (under a different user name) and are getting similar responses back via that community as well - ie do not take your packs down that low and start your flights with 100% charge.

 

[DaBone]

I quote myself from another thread

"With my Phantom, I often flew with batteries that were not fully charged, but with my Inspire 1 I have only done it once. Never again.

I mostly photograph houses and are usually only in the air for 4-6 minutes, so I thought it was okay to fly with a battery that was 75 percent charged.

This time it was a house that was next to a fairly busy road.
No problems with starting and fly up and away to the other side of the road, but 2 minutes later, I received the first warning. 30% ..
Thought immediately that this was not okay and started to take home the drone. Took a few seconds and then it was down to 10%. Got cold sweat ..
Seconds later it was down to 3-5%, I can´t remember, becouse it started to descend on the busy road!
Managed to get it to abort the descent and get it over the road and into the garden to the house, I photographed.. 1% left when I landed."

If Shazbot4 is correct it would have fall out of the sky, down on the busy road... OMG!

Lucky it didn´t and it should not. Instead, it started descend, as it should.

I can imagine that the drone thought it was on the ground, as it was only a foot up in the air and therefore shut down.

 

[Mike Ellgood]

You should NEVER be flying your packs down to 10%. If you were flying anything RC you would probably lose it if you were flying your packs down to those sort of levels and you would get the same behaviour from any lipo pack.

Whilst I agree that the 20% rule applies to Lipo polymer batteries and I have been modelling since they came out... Lithium-ion batteries are used on the inspire.... this is what it says on the box that my new battery came in and these can be drained to zero without any harm.. like your phone battery... But they are flawed also in the fact that they give everything until they reach 99% and then they die imediately

The issue is that the calculation the battery does on its levels of charge are flawed unless fully charged

 

[Kilrah]

Li-ion and Li-po behave just the same, whether they can be drained to "zero" only depends on what is considered "zero"... behind the scenes their minimum acceptable voltage is the same.

On the I1 (like all other "smart batteries" used in phones, laptops, cameras etc) "zero" is considered "minimum save level not to damage the battery".
The I1's battery will shut itself down at 0% like your phone shuts itself down at 0%. As long as you understand it, there's no issue.

The big difference that is at play here is that high discharge rates like on a multicopter capacity-based measurement is a bit more prone to errors than on things that discharge their batteries in more than 2h at the fastest.

 

[The Editor]

.. Lithium-ion batteries are used on the inspire....

No they are not......Lithium ion chemistry simply does not possess the right characteristics to give up large amounts of power which is required for RC applications.

The Inspire packs are Lipo (Lithium Polymer)

 

[Mike Ellgood]

No they are not......Lithium ion chemistry simply does not possess the right characteristics to give up large amounts of power which is required for RC applications.

The Inspire packs are Lipo (Lithium Polymer)

I will take a picture of the dji box that my new battery came in and it says lithium-ion

honest guv

 

[The Editor]

I will take a picture of the dji box that my new battery came in and it says lithium-ion

honest guv

Then take a look at the casing of your pack where it says Lipo.
The nominal voltage is 3.7v per cell.
The box is probably a Chinglish bad typo/translation.
Believe me, if you tried to pull 80-100 amps (which the Inspire can demand on full climb out) a Lithium Ion pack would not last very long.

Also, check out DJI's specs page for the batteries form the Inspire.

 

[Kilrah]

The Inspire uses some "unusual" variation of Li-Po chemistry as it's safely charged to 4.35V/cell instead of the usual 4.2V.

But again that doesn't matter for the user - what does is the percentage and voltage combination.

 

[Mike Ellgood]

Then take a look at the casing of your pack where it says Lipo.
The nominal voltage is 3.7v per cell.
The box is probably a Chinglish bad typo/translation.
Believe me, if you tried to pull 80-100 amps (which the Inspire can demand on full climb out) a Lithium Ion pack would not last very long.

oops I was looking at wrong box .. ok the p3p uses lithium - ion .. well it doesn't suffer from battery issues.. lol

I had 2 inspire and 2 p3 batteries delivered week... and got confused.. well I am a OAP with dementia

 

[The Editor]

The Inspire uses some "unusual" variation of Li-Po chemistry as it's safely charged to 4.35V/cell instead of the usual 4.2V.

But again that doesn't matter for the user - what does is the percentage and voltage combination.

Agreed - its a weird 'high density' Lipo as anything over 4.215v would kill a standard pack.

Also agree that it is not important as far as the user goes, however there is huge misunderstanding by many with zero not being zero.

 

[The Editor]

oops I was looking at wrong box .. ok the p3p uses lithium - ion .. well it doesn't suffer from battery issues.. lol

I had 2 inspire and 2 p3 batteries delivered week... and got confused.. well I am a OAP with dementia

The P3 uses 15.2v 4s Lipos http://www.dji.com/product/phantom-3/spec

RC just demands too much to be able to be powered from Li-ion.

 

[Kilrah]

there is huge misunderstanding by many with zero not being zero.

Unfortunately... and I have trouble understanding why as nowadays everybody has a smartphone, and all smartphones will shut down at 0%... so it shouldn't be that hard to understand.
Of course, you need to somehow "forget" the usual RC experience you might have acquired over the years. Or rather put it aside when you use DJI stuff, and think in terms of consumer electronics instead
I for one think that should have been done a decade ago for all RC batteries.

 

[Shazbot4]

this is just getting comical now. you guys are going around in circles. I can't add anything new because i'll just be repeating myself.

i'll leave it at this. DJI will crash your inspire if you fly the battery to 10%. it has nothing to do with the hardware, it's all the software and there is no logic behind it.

 

[BroxAg]

this is just getting comical now. you guys are going around in circles. I can't add anything new because i'll just be repeating myself.

i'll leave it at this. DJI will crash your inspire if you fly the battery to 10%. it has nothing to do with the hardware, it's all the software and there is no logic behind it.

I'm just curious. What battery % would you like the safety landing limit to be set at then? (Keeping in mind that this is a figure that DJI have put in place to stop individual cells drawing below a set voltage and therefore preserving the life of the battery)
Would you be happy if it was 3%? Or do you want removed all together?
We have already established that batteries that are dropping from 50% to 3% rapidly are not the norm. So under normal flying conditions the 10% threshold would be fine as you shouldn't be flying anywhere near that limit.

If you changed the limit to 3% then the faulty batteries would still be thrown into a forced landing.
If you removed it all together then I would estimate that you probably have 10-15 seconds max to get the I1 on the ground before there was just no more voltage left whatsoever causing total shut down of all systems and who know what issues that may cause long term!
In either situation I would say the outcome has a strong possibily of being less than desireable.

The point I am trying to make is that this forced landing limit of 10% is a safety margin. If it was removed it could result in a damaged battery and possibly damaged circuits/components/hardware......