Pre-flight testing of ESC?

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So I've recently learned about ESC's, their function, and just how vulnerable/fragile they are. From people having blown ESC's from something as minor as a tipover, or a light crash against a small branch, I'm actually quite concerned about them. I have had a very minor crash with my Phantom 2 (non-vision), I clipped a branch and my phantom fell 2 feet into thick fluffy snow. All the props had stopped spinning, and I immediately turned the phantom off as soon as I could. It wasn't a big deal, apart from 2 cracked props. One of them was very hard to remove due to the force of the impact, but I removed and replaced it just fine. I have flown since, and have had zero issues flying, noticed no erratic behaviour. In fact, I didn't even know about blown ESC's until yesterday.

One thing I'm wondering is, if perhaps the extreme cold may have saved my ESC from overheating and blowing. It was about -25 to -30°c (around -13°F to -22°F) that day. But then again, I've read multiple accounts of people crashing all the time, tipovers, etc, without a single blown ESC, and others lost their ESC's while lightly grazing tall grass.

My question is, is there a way to test ESC's pre-flight to make sure they won't blow out on you mid-flight? I haven't opened up my shell yet to verify the integrity of the board. I will do that tonight, make sure the MOSFET's are in good shape, along with the soldering of the cables linking the motor.

Many thanks!
 
Well, I wonder about the ESC blowing with only a simple tree limb hit when mine did not. When a puff of wind pushed mine into a pine tree it stuck right there. I walked over and pulled it out of the tree. Props started right up. So if stopping a motor blows the ESC, I must have just been lucky. Mine had power to it and motor held by limb. Got a shock when the rotors started as soon as it came out of the tree. Especially when the controller was across the yard. Dumb move.
 
You said you didn't even know about ESCs until yesterday. Did you later have an ESC problem or you just learned about them?

To answer your question about a pre-flight way of telling if an ESC might blow during the flight: If your rotors all spin equally well, that is about all you can do. Unless you want to land to compare the temperature in the ESC area. But, I think all you can really do is try avoiding hitting anything.

I doubt the cold kept an ESC from blowing, unless it blew the next day on startup. BTW, the board looks bit fragile, but when I put pressure on the board, it is quite strong. It is secured by only two Phillips screws, but it is adequate.

You will know when one goes bad, so in the meantime, just enjoy your flying!
 
I have never had an ESC problem, I just learned about them more extensively this week, and it left me scratching my head as to why my Phantom 2 still works just fine. Especially considering some people have blown theirs over the most minor of incidents.

I'll do a few tests today and let the motors run (without) props for 5-10 minutes and see if I hear any strange sounds that would indicate one or two props spinning slower than the rest.
Thanks for your help folks! If you have any other way of testing the ESC, let me know!
 
Prophecies said:
I have never had an ESC problem, I just learned about them more extensively this week, and it left me scratching my head as to why my Phantom 2 still works just fine. Especially considering some people have blown theirs over the most minor of incidents.

I'll do a few tests today and let the motors run (without) props for 5-10 minutes and see if I hear any strange sounds that would indicate one or two props spinning slower than the rest.
Thanks for your help folks! If you have any other way of testing the ESC, let me know!

If you do stall a prop or crash and the ESC does not blow, I would suggest the next flight should be low risk (low height, near distance) and give it a good run in ATTI to work the ESCs to see if one is about to go.

But basically - you can't tell. :(
 
After doing a few tests, I've noticed something unusual. So I put on my props and hovered around my apartment for a few minutes. After landing, I left the motors idle for a bit. Slowly, the props started spinning faster and faster, almost as if it were getting ready to take off, and it almost did, and almost tipped over forward. I was not touching the sticks at all. So when I heard the increased RPM of the motors, I immediately shut them off. I can reproduce this issue. When the motors are off and I turn them on, all is well, there is no issue. The problem arises when I'm flying, land, and don't touch the sticks anymore. Is this normal? Does the throttle stick need to be locked in the down position after it has landed?

I have tried this in both GPS mode (no sats connected since I was indoors and my apartment has a ton of concrete), and ATTI mode. Both modes gave me the same issue. Granted, it's not much of an issue because I normally always shut down the motors after I've landed, but this has definitely made me curious.

I did start the motors and leave them running for about 5-10 minutes, noticed no difference in sound from one motor to the next, they all seem to be spinning at the same speed, which is good, would seem like my ESC's are just fine.
 
It is 'normal' for the motors to rev up after landing.

The a/c still 'thinks' it is flying.

Turn off motors when flight is finished.
 
Prophecies said:
After doing a few tests, I've noticed something unusual. So I put on my props and hovered around my apartment for a few minutes. After landing, I left the motors idle for a bit. Slowly, the props started spinning faster and faster, almost as if it were getting ready to take off, and it almost did, and almost tipped over forward. I was not touching the sticks at all. So when I heard the increased RPM of the motors, I immediately shut them off. I can reproduce this issue. When the motors are off and I turn them on, all is well, there is no issue. The problem arises when I'm flying, land, and don't touch the sticks anymore. Is this normal? Does the throttle stick need to be locked in the down position after it has landed?

I have tried this in both GPS mode (no sats connected since I was indoors and my apartment has a ton of concrete), and ATTI mode. Both modes gave me the same issue. Granted, it's not much of an issue because I normally always shut down the motors after I've landed, but this has definitely made me curious.

I did start the motors and leave them running for about 5-10 minutes, noticed no difference in sound from one motor to the next, they all seem to be spinning at the same speed, which is good, would seem like my ESC's are just fine.
Yep, like N017RW said. Turn off after landing.
viewtopic.php?f=4&t=33457
 
P2V+ V2 Post Crash RPM test, before rebuild: In the photo attached I've written on the props the measured RPM of each motor at idle. The lower left motor had the shell arm bent and the LED no longer blinks, but the quad still does the LED sequence successfully on the other arm) No flight attempted since shell damage etc, just wanna know what the different measurements mean, if anything. Several small crashes and rollovers in grass during its short lifetime, I learn the hard way usually, so I suspect debris and ESC damage. My plan is to rebuild with new motors and ESCs.
 

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