DJI Cold weather Info FW 1.6

[Droider]

DJI released 1.6 as we all know to help protect batteries and AC while flying in 'COLD' weather.
Does anyone know just what DJI class as 'COLD'
Does anyone know what temperature the AC is restricted / put into limp mode

The other concerning thing is the statement that the pack will shut off if the voltage drops below 3V to protect the battery! WHAT ABOUT THE AC! I would rather burn a pack than the ac.

In the good old days when programming ESC's was required the first thing you did was turn off the low voltage protection.

Please anyone that talks to DJI ask them to give pros switchable options or better still a separate GoProAPP!

Anyone testing these features to establish parameters I would be more than happy to share.

 

[Kilrah]

Even if the pack didn't turn off at 3V your AC would fall dead to the ground in the following seconds. When a lipo gets to that point its voltage is falling off a cliff and can't keep the motors running anyway.

Fly responsibly as you should and never get any close to that.

Envoyé de mon SM-G920F en utilisant Tapatalk

 

[Droider]

Found this

QUOTE
"Flying DJI aircraft in winter can be fun, but we have heard that some of our users have experienced issues when flying in cold weather. Did you know that as the temperature drops, so does the performance of the LiPo battery inside your aircraft? Read on to find out how to look after your battery and keep yourself in the air.

The Science

LiPo, or Lithium Polymer batteries drain faster the colder they get because the chemical reactions that they use to create electricity are slowed. This starts to occur at temperatures lower than 59°F (15°C) and is a known issue of all LiPo batteries.

At high altitudes where air pressure is low, motors on an aircraft have to spin faster to produce enough lift, meaning even more power is needed, in turn accelerating battery drain.

What this Means

In extreme cases, a battery could drain below 3V, causing reduced thrust or even battery shutoff due to over-discharge protection systems designed to keep your battery healthy.

Hot Tips for Beating the Cold

1. Make sure batteries are fully charged before each flight.
2. Warm batteries to 25°C or more before flight. We recommend using a battery heater.
3. Hover the aircraft for around a minute to allow the battery to warm up.
4. Turn on “Show Voltage on Main Screen" on the "Aircraft Battery" page of the DJI Go app. Do not continue flying if battery voltage drops below 3.2V."

 

[andrew259]

I've just bought a IR temperature gun to help measure battery temps... Very cheap.


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[Droider]

Even if the pack didn't turn off at 3V your AC would fall dead to the ground in the following seconds. When a lipo gets to that point its voltage is falling off a cliff and can't keep the motors running anyway.

Fly responsibly as you should and never get any close to that.

Envoyé de mon SM-G920F en utilisant Tapatalk

Totally agree but the motors wont just stop. I would rather there not be a cut off to go wrong.

 

[Droider]

I've just bought a IR temperature gun to help measure battery temps... Very cheap.


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I guess thats for when they are not in the AC.

 

[andrew259]

Yes... It gives me an idea at least - but it's actually for weather conditions too. If I have some form of insulation I can check the internal temperature of that to ensure the batteries can be kept warm at the right temp.


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[rilot]

I've not updated mine yet, but are they saying that the craft will be in limp mode if the batteries are at < 25C? I live in the UK and the weather rarely gets that hot even in summer.

 

[MrDrone]

good point ... we may get 25C about 3 days a year!
I read somewhere that 15C is the key temp that the FW will use to trigger battery protection.

 

[The Editor]

I've not updated mine yet, but are they saying that the craft will be in limp mode if the batteries are at < 25C? I live in the UK and the weather rarely gets that hot even in summer.

No - there appears to be a hard cut off (or non start threshold) of 15 degrees.
Above this the motors will start, below they won't and a warning message appears.
From my testing, once you get down into the 3.3 to 3.4 v per cell territory your throttle is limited to prevent a voltage drop under load into dangerous land!
This on itself is not a bad thing since this is no different to a lipo losing its 'punch' at nearly depleted levels.
Recreational RC fliers have known this for years and you really shouldn't be still up in the air at 3.3v per cell territory in any case.
This is more for the 'out of the box, I've never used a lipo and I dont want to read a manual gang'
It's idiot damage limitation.

 

[rilot]

So, 15C then. That's rubbish. Why can't I just hover the **** thing for 1 minute to warm the batteries? I'm not buying DJI's flipping battery warmer.

 

[Fanti]

No - there appears to be a hard cut off (or non start threshold) of 15 degrees.
Above this the motors will start, below they won't and a warning message appears.
From my testing, once you get down into the 3.3 to 3.4 v per cell territory your throttle is limited to prevent a voltage drop under load into dangerous land!
This on itself is not a bad thing since this is no different to a lipo losing its 'punch' at nearly depleted levels.
Recreational RC fliers have known this for years and you really shouldn't be still up in the air at 3.3v per cell territory in any case.
This is more for the 'out of the box, I've never used a lipo and I dont want to read a manual gang'
It's idiot damage limitation.

So what if you are on the verge of making it back to the homepoint ? Thats wehen you need punch ! Whats better, a maybe weak battery or loosing and crashing your copter ??

 

[The Editor]

So what if you are on the verge of making it back to the homepoint ? Thats wehen you need punch ! Whats better, a maybe weak battery or loosing and crashing your copter ??

Being home and SOD well before you ever get anywhere near these sort of levels.
If you know you shouldn't be there, you don't go there.
I have been flying RC for 30 years and have never lost an aircraft yet due to my own ignorance of flying into plateau ranges I shouldn't.

 

[kcobello]

I read this thread and would like to know the lowest temp to safely fly my rig. Would 32 deg and rising be a good response for the people that ask me to image in cold weather? I sometimes get the uneducated, roll eyes, response from a couple that.."I can fly it in the cold weather, why you worried"...when they don't own and didn't spend $6000 of their own money on it....

 

[The Editor]

I read this thread and would like to know the lowest temp to safely fly my rig. Would 32 deg and rising be a good response for the people that ask me to image in cold weather? I sometimes get the uneducated, roll eyes, response from a couple that.."I can fly it in the cold weather, why you worried"...when they don't own and didn't spend $6000 of their own money on it....

With a pre heated battery, I think 32f/0c is sensible.
Don't forget, neither the X3 or the X5 are rated under that temperature anyway.
Yes, people have flown in minus 25 etc, yes I am sure someone, somewhere will fly it in minus 40 but really do your fingers and the rest of your body function that well at those temps? I know mine don't.
Working below 32f is outside of DJI spec and may (notice I said may and not will) cause unexpected/poor results.

 

[The Editor]

So, 15C then. That's rubbish. Why can't I just hover the **** thing for 1 minute to warm the batteries? I'm not buying DJI's flipping battery warmer.

Get some of these instead then - they are actually pretty good.
Turnigy Programmable Lipo Battery Warmer Bag (12v DC)
And to be fair, the DJI warmer is good as well - only uses around 5% of charge to get the pack toasty.
Can recommend the Tunigy bags though.

 

[SRH]

I live in the frozen northeastern corner of Montana... We have not had temps above freezing for well over a month and I have been flying most mornings with the temps below zero without issue. I keep the battery packs warm in my vehicle before flight plus they all have the dji battery insulation stickers on them.... When I take off I let the aircraft hover for a few minutes and watch the batteries warm up. Biggest issue I have encountered is the vision positioning system gets confused and will not allow you to enter travel mode. I have to bring it inside and let it warm up for a few and then try again.

Just to be clear I have done many, many, many test flights to see what affect the cold would have. No way would I have just taken off and put my considerable investment at risk but I feel comfortable that if you take your time and let things stabilize and warm up and don't fly aggressive the aircraft works well below the stated temps.

 

[kcobello]

Thanks for the responses guys. I will use common sense and the info. I will invest in the DJI battery warmer though.

 

[andreweio101]

I am pretty hacked off yet another quiet software "enhancement" by DJI crippling the use of my Inspire as they seem to deem that if the batteries are below a certain temperature then DJI has decided you are not allowed to earn your money to recover the vast expenditure to become a professional pilot.

I understand if the phantom range has these training wheels attached but the inspire which they rate at -10 degrees on their website is actually disabled at 5 degrees

I looked like an amateur today as had amazing winter day with the first clear blue skies the first in a long time, to be told by the app battery temp low heat it up. This is done to protect the pilots embarrassment supposedly but in reality it is doing the opposite by alienating a client when the weather is good and you are in the middle of a field and can't fly.

Okay so I do have a DJI battery heater and after waiting a while for the battery to be hot enough the inspire sparks to life and the, reports then only 90% battery left, surely the battery heater is only a way for DJI to increase the revenue on heaters and batteries? And surely the battery heater has taken as much juice out of the battery as the cold weather.

As a professional -ish commercial uav surely the app should just display an alert and say "it's cold - Watch out" just like my car. Which does not disable me as there might be ice on the road!!

Rant over, and seeking new client


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[DaBone]

I was out flying last night and it was -12C. Flew up to 120 meters and traveled around a bit .. Sure, I notice that the battery is quickly drained, but it worked as it should and at that height it was surely colder.