We all know that electronics and heat are not very fond of eachother. As we all have seen, when the MAVIC is turned on and left there while tinckering with settings or upgrading the Titanium heat sink plate gets quite hot, while the fan is working hard to vacate the heat.
This brings the question: What's the maximum recomended time that we could leave the MAVIC on the following conditions to avoid thermal damage of the electronics inside?

For the sake of simplicity and having a controlled enviroment let's say that we have the following conditions:

- Regulated temperature enviroment at constant 21C (a room with AC).

- The MAVIC has no obstruccion on the air flow of the fan FWD & AFT i.e. no gimbal cover.

- There is no direct air flowing into the MAVIC.

If there are some other constraints or information feel free to add them up.

It would be interesting to have a DJI's representative opinion on this, maybe DJIKen?

No one? Thought some of you guys might have some ideas.

I think if you stay within these operating temperature range you can leave your aircraft on as long as you want.

32 degrees to 104 degrees.

If the fan is running, you should be okay. (Cringe!)

fansca9280ea Posted at 2017-6-13 06:43
Heatsink should be hot, it indicates it's doing its job and pulling heat away. Leave it on all day and play with settings

That's right the heat sink should be hot. But my question lays on the amount of time that the heat sink is capable of exchange heat in an effective manner. Without having the added advantage of extra airflow due to flight.

Griffith Posted at 2017-6-13 07:30
If the fan is running, you should be okay. (Cringe!)

Hahahah I did cringe a bit. This then brings me to wonder if the Mavic has some kind off thermal protection which turns of the AC after a temperature threshold is reached. Also would be nice to have some kind of auto-off option while the AC is on standby.  

Maxi3D Posted at 2017-6-13 06:34
I think if you stay within these operating temperature range you can leave your aircraft on as long as you want.

32 degrees to 104 degrees.

That's right. Those are operating temperatures but I am more interested in internal temperature and mostly optimal temperature for the internals.

I don't think the heat sink is made of titanium.

I have heard of people running down batteries by just letting them sit while on. Probably takes an hour but I don't know for sure.

Glenn Goodlett Posted at 2017-6-13 08:37
I don't think the heat sink is made of titanium.

I have heard of people running down batteries by just letting them sit while on. Probably takes an hour but I don't know for sure.

Maybe aluminum then,  but of I do recall correctly I did read somewhere that it was titanium.

That's quite interesting, to run down the batteries like that. I rather change the internal autodischarge program of the batteries and let them do it by themselves. 1 hour of the drone sitting and getting hot does not makes me feel very confident of the outcome in the long run.  

Um, have you noticed that as soon as the fan starts, the heat sink cools down?

That should answer all questions.

AACY Posted at 2017-6-13 07:44
Hahahah I did cringe a bit. This then brings me to wonder if the Mavic has some kind off thermal protection which turns of the AC after a temperature threshold is reached. Also would be nice to have some kind of auto-off option while the AC is on standby.

I'm pretty sure the battery turns off if overheated.  As for thermal protection of the rest, not sure.  The results might be tragic in either case :-)

AACY Posted at 2017-6-13 07:46
That's right. Those are operating temperatures but I am more interested in internal temperature and mostly optimal temperature for the internals.

Optimal is interesting.  Optimal for computational speed is 0 degrees Kelvin.  Max operating temperatures for most processors are 50 - 70 degrees C.  But the optimum rule is "the colder, the better".  That's the rule for processors, other devices in the Mavic, like cameras, barometers, accelerometers and batteries don't do so well in extreme cold.

Griffith Posted at 2017-6-14 11:32
I'm pretty sure the battery turns off if overheated.  As for thermal protection of the rest, not sure.  The results might be tragic in either case :-)

That's right a Mid-flight shutdown would be spectacular. That's why I wondered if this safety measures might be implemented when the drone is sitting down and not flying.

Griffith Posted at 2017-6-14 11:48
Optimal is interesting.  Optimal for computational speed is 0 degrees Kelvin.  Max operating temperatures for most processors are 50 - 70 degrees C.  But the optimum rule is "the colder, the better".  That's the rule for processors, other devices in the Mavic, like cameras, barometers, accelerometers and batteries don't do so well in extreme cold.

Thanks for you input! That's more like it. At 50 - 70C I will be comfortable leaving the device run for a while.

when i mede settings i put an extra fan in front, but i dont think it is a problem if nternal fan is running...

Tealk Posted at 2017-6-14 20:58
when i mede settings i put an extra fan in front, but i dont think it is a problem if nternal fan is running...

Indeed an external fan would greatly help to accelerate the amount of heat transferred into the air.

AACY Posted at 2017-6-14 20:21
That's right a Mid-flight shutdown would be spectacular. That's why I wondered if this safety measures might be implemented when the drone is sitting down and not flying.

I've seen one case posted where it appears that a battery cell shutdown mid-flight. there are 3 cells in the Mavic battery and the battery voltage suddenly went to 7.5 volts (normally around 11). I don't know if it was a thermal shutdown, cell failure,  or some other event.

Griffith Posted at 2017-6-15 06:19
I've seen one case posted where it appears that a battery cell shutdown mid-flight. there are 3 cells in the Mavic battery and the battery voltage suddenly went to 7.5 volts (normally around 11). I don't know if it was a thermal shutdown, cell failure,  or some other event.

Wowww quite interesting case. The nominal voltage should be 11.1 in total so each cell should be giving around 3.7. Totally 7.5 means that one of the cells went dead. Maybe, but it would be very strange that the intelligent circuit shot down one of the cells because it's the same as turning down the entire battery. 7.5 is not enough voltage to keep the ESCs running, they would shoot down, letting the Mavic drop like a brick. Most probably there was an internal error on the cell and went kaput midflight.

Cheers!

When I download files from my Mavic directly to the computer I put a small desk fan in front of the air intake / fan to increase airflow.

4wesomeAdam Posted at 2017-6-15 08:22
When I download files from my Mavic directly to the computer I put a small desk fan in front of the air intake / fan to increase airflow.

That's indeed a good way to go!

AACY Posted at 2017-6-15 08:00
Wowww quite interesting case. The nominal voltage should be 11.1 in total so each cell should be giving around 3.7. Totally 7.5 means that one of the cells went dead. Maybe, but it would be very strange that the intelligent circuit shot down one of the cells because it's the same as turning down the entire battery. 7.5 is not enough voltage to keep the ESCs running, they would shoot down, letting the Mavic drop like a brick. Most probably there was an internal error on the cell and went kaput midflight.

Cheers!

The only upside, if you can call it that, is that the other electronics are still running and data is being logged. :-(

Griffith Posted at 2017-6-19 09:44
The only upside, if you can call it that, is that the other electronics are still running and data is being logged. :-(

Exactly, which is necessary for the future analysis and possible investigation of the cause of that failure.

From another Mavic Forum, which should help you in your quest

http://mavicpilots.com/threads/g ... .17023/#post-195336

Nikon 1 Posted at 2017-6-21 22:34
From another Mavic Forum, which should help you in your quest

http://mavicpilots.com/threads/gimbal-bubble-tests-some-observations.17023/#post-195336

Wowww!!! this is great information. Thanks for sharing it!

Cheers!

AACY Posted at 2017-6-21 23:09
Wowww!!! this is great information. Thanks for sharing it!

Cheers!

What we try to do, help each other.

Good Flying

The Mavics internal fan is quite capable of maintaining the temp without worry . If someone is concerned about high temps from taking an exorbitant time changing setting or updating firmware then set the Mavic over or near your AC vent ,lol.

rydfree41 Posted at 2017-6-22 04:00
The Mavics internal fan is quite capable of maintaining the temp without worry . If someone is concerned about high temps from taking an exorbitant time changing setting or updating firmware then set the Mavic over or near your AC vent ,lol.

Indeed that's a great idea. but my concern was regarding the capability of the system to exchange heat with the environment without reaching temps that could damage permanently the internals. On @Nikon 1 post's there is a very interesting analysis which shed a lot of light on this subject.

AACY Posted at 2017-6-22 04:54
Indeed that's a great idea. but my concern was regarding the capability of the system to exchange heat with the environment without reaching temps that could damage permanently the internals. On @Nikon 1 post's there is a very interesting analysis which shed a lot of light on this subject.

Yes the anlyasis actually agreed with my post in that thread . the mavics fan is quite capable of handling the heat .

AACY Posted at 2017-6-13 08:47
Maybe aluminum then,  but of I do recall correctly I did read somewhere that it was titanium.

That's quite interesting, to run down the batteries like that. I rather change the internal autodischarge program of the batteries and let them do it by themselves. 1 hour of the drone sitting and getting hot does not makes me feel very confident of the outcome in the long run.

mavic would cost twice if the heat sink was made of titanium.... i read somewhere that it was adamantium....