How long do you think these motors will last?

sdjackaerial · Mar 3, 2015

I know the easy response is "depends on how much you fly". Ok.
Say I fly no less than twice a week with three batteries worth of flying each time (approx 1 hr).
Being new to RC aircraft, what am I looking for to see the motors change and give warning? I would hope I could hear a change in the motors before it falls from the sky from a motor failure. I'm assuming it can't fly with three..lol.

blade strike · Mar 3, 2015

These are brushless motors.. if taken care of they will outlast the craft.

sdjackaerial · Mar 3, 2015

blade strike said:
These are brushless motors.. if taken care of they will outlast the craft.

ok, cool. Can you give any advice on taking care of them? (again--beginner here)

PetePerrim · Mar 3, 2015

In my experience with flying various types of quads and hex's, the motors will just keep on going as long as they don't get too much dust or grit in them. I've flown several hundred kilometres with my little Phantom and that baby just keeps on truckin. I check the motors relative temperatures against each other every now and again when I land and I also twirl the motors between my fingers to see if any of them feel markedly different to each other but 'touch wood' so far, so good. IMHO you're far more likely to have an ESC go postal on you without any warning than a motor.

InspiredOne · Mar 3, 2015

PetePerrim said:
... you're far more likely to have an ESC go postal on you...

ESC stands for...?

EDIT: Is there source where one can find all the abbreviations and their meanings for UAV flying?

Kilrah · Mar 3, 2015

Motor "electronic speed controller".

InspiredOne · Mar 3, 2015

Kilrah said:
Motor "electronic speed controller".

I would have never guessed that one.

Thanks!

The Editor · Mar 3, 2015

The motors will last forever (pretty much) - there are no moving parts in them.

The bearings wont! - On average, for this size motor (and rotational speed) bearings should be changed around every 80 hours or so - even if they are ceramic bearings.
Bearings should be part of regular flight maintenance procedure

perryseyes · Mar 3, 2015

So out of curiosity what's the life span of the esc, how many hours approximately?

The Editor · Mar 3, 2015

perryseyes said:
So out of curiosity what's the life span of the esc, how many hours approximately?

Assuming they don't fail - Indefinitely!
The most likely thing to fail on an esc will be a FET (Field Effect Transistor) which does the heavy current switching as part of an array. These will either work.... or not, there's no middle ground. I'm afraid an esc failure means a sudden crash (not so with a hex as they can fly on five motors). Most electronic components will follow a 'bath-tub' curve failure rate which means they will either fail fairly early on in their life cycle or they will go on to be reliable.
Certain things WILL however put them under stress and potentially contribute to a failure - fouling the props on trees, bushes etc with the motors still powered will place stress on the esc's by asking them to pass more current than they should.

jon b · Mar 3, 2015

Good thread. No dumb questions when it comes to understanding your aircraft and how to use/maintain it. Thanks!

Kilrah · Mar 4, 2015

perryseyes said:
So out of curiosity what's the life span of the esc, how many hours approximately?

The downside of electronics vs mechanics is that this cannot typically be determined.
On something mechanical you can do preventive maintenance (cleaning, greasing, visual inspection / measurement and replace worn out or out of tolerance parts).
None of that applies to electronics, except from a serious design error or component misuse all you can do is assume it will work indefinitely... Until it fails.
Determining a reliable life span would be horribly difficult.

Rig · Mar 5, 2015

Can we change out our bearings without voiding any warranties or is this a send to DJI procedure?

The Editor · Mar 5, 2015

On ALL the motors I have used thus far, bearing changes have been a very simple job. Since DJI are using the 3510/KV350 E800 motors in the Inspire there should be no good reason why bearings are not a user replaceable part - unless DJI come out with some mumbo jumbo about how it must be done by an authorised service centre, blah, blah etc..... To make money.

slim.slamma · Feb 26, 2016

The Editor said:
On ALL the motors I have used thus far, bearing changes have been a very simple job. Since DJI are using the 3510/KV350 E800 motors in the Inspire there should be no good reason why bearings are not a user replaceable part - unless DJI come out with some mumbo jumbo about how it must be done by an authorised service centre, blah, blah etc..... To make money.

Have you changed yours or is it "mumbo jumbo"?
Reached 80 hrs?

unyks · Feb 26, 2016

The Editor said:
The motors will last forever (pretty much) - there are no moving parts in them.

The bearings wont! - On average, for this size motor (and rotational speed) bearings should be changed around every 80 hours or so - even if they are ceramic bearings.
Bearings should be part of regular flight maintenance procedure

That's why DJI is suggesting maintenance after 50 hours of flighttime but i don't know if changing the bearings is part of that...

Chris

fei8820 · Feb 26, 2016

logically if both esc n motor no crash and nothing happen it possible live longer than human... as well all the electronic component inside... my own delta wing n mustang p51 brushless motor n esc still going strong... erm 7years already ? i have no idea how many flightime it seems it work forever if you setup correctly ~~~ and make sure there is no tiny debris rock or sand inside your motor.... and make sure it always rotate freely ... no binding ...

slim.slamma · Feb 26, 2016

fei8820 said:
logically if both esc n motor no crash and nothing happen it possible live longer than human... as well all the electronic component inside... my own delta wing n mustang p51 brushless motor n esc still going strong... erm 7years already ? i have no idea how many flightime it seems it work forever if you setup correctly ~~~ and make sure there is no tiny debris rock or sand inside your motor.... and make sure it always rotate freely ... no binding ...

10;4

famorim2000 · Mar 7, 2017

Great discussion.

I was looking right about that. I am about to start an operation to have 4 custom Quadcopters mounted with DJI e800 or E1200 motors to flight over an middle sized area in order to performing a set o tasks with 24x7 coverage. So, I have 1440 minutes per day with 12 flights of 30 minutes per each aircraft per day. It means 6 hours flight per drone in a normal day of operation.

So, based on that premisse to have a maintenance each 80 hours, I will need to service these motors each 13 day. Is that right ? Is there a easy way to identify when bearings need to be replaced ?

Thanks