Flying low I lost control and crashed at low speed. No more than 15 inches high

I quickly disarmed the motors but in less than a second the ESC and motor fried.
This is the second time it happens. Any advice ?

How normal is this ?
I can ensure is not solder/ wiring problem

I'll post a picture as soon as I have access to a computer. Upload from the phone isn't working.

Thanks

Can at least the motor be recovered ?
Here are the photos.

Thanks

Yikes! What size ESCs are those, and how close are the motor mount screws to the coils? I can see this happening if it was just laying there trying to spin the props, but if you disarmed it quickly as you said, it must be some underlying problem

(01-May-2017, 05:15 PM)RENOV8R Wrote: Yikes!  What size ESCs are those, and how close are the motor mount screws to the coils?  I can see this happening if it was just laying there trying to spin the props, but if you disarmed it quickly as you said, it must be some underlying problem

Hi Renov8r, 

12a.
Here is the esc I´m using.
http://produto.mercadolivre.com.br/MLB-8...-racer-_JM

And yes, I´m sure I cut the motors in less than a second after hitting the ground.
What I noticed is that during the crash, the prop from this motor completely stopped.

Anything I could do to prevent this in your opinion ?

don't use 12A on 5" props...
20-30a depending on the props you use.. 12 is... very low

Make sense. I'll see if my dealer has anything available
Will 4 ESC 20 or 30a change the way the bird responds also ?

(01-May-2017, 04:18 PM)flabombarda Wrote: Can at least the motor be recovered ?

No, your motor is ruined. I can see on the picture that the windings have overheated. This will destroy the enamel insulation on the wires. At the same time, it would have got so hot that the magnets will have lost a lot of their strength.

I'm puzzled though. The motors look like EMax 2204 2300kv. Is that correct? Also, what propellers are you using?

(01-May-2017, 06:51 PM)unseen Wrote: No, your motor is ruined. I can see on the picture that the windings have overheated. This will destroy the enamel insulation on the wires. At the same time, it would have got so hot that the magnets will have lost a lot of their strength.

I'm puzzled though. The motors look like EMax 2204 2300kv. Is that correct? Also, what propellers are you using?

Correct. Motors emax 2204 2300kv

Props 5030.
Any recommendations ?

(01-May-2017, 06:34 PM)flabombarda Wrote: Make sense. I'll see if my dealer has anything available
Will 4 ESC 20 or 30a change the way the bird responds also ?

Yes, it won't spontaneously combust!  (Sorry, I know it isn't funny but I couldn't resist)

(01-May-2017, 08:00 PM)RENOV8R Wrote: Yes, it won't spontaneously combust!  (Sorry, I know it isn't funny but I couldn't resist)

No issues! In Brazil we say we lose the friend but never the joke 

(01-May-2017, 07:11 PM)flabombarda Wrote: Correct. Motors emax 2204 2300kv

Props 5030.
Any recommendations ?

In that case, your 12A ESCs are fine and that's not the cause of them burning up.

You must look for another explanation.

Possible causes are the screws that you have mounted the motors to the frame with are too long and are shorting the motor windings, there is a short between the ESC and the frame (remember, carbon fibre conducts electricity), you took longer to disarm the craft than you thought.

Are you arming and disarming by using stick positions or via a switch? If you use a switch, you can disarm pretty much instantly. The stick commands take longer.

(01-May-2017, 10:12 PM)unseen Wrote: In that case, your 12A ESCs are fine and that's not the cause of them burning up.

You must look for another explanation.

Possible causes are the screws that you have mounted the motors to the frame with are too long and are shorting the motor windings, there is a short between the ESC and the frame (remember, carbon fibre conducts electricity), you took longer to disarm the craft than you thought.

Are you arming and disarming by using stick positions or via a switch? If you use a switch, you can disarm pretty much instantly. The stick commands take longer.

My guess is that the cause of the burning up was, there was still some throttle while the propeller hit the ground and stopped spinning, that´s the only explanation I can find, 
the screws were just fine, and this motors was running normal for at least 20-30 batteries.
I need to disarm them earlier in case of a crash.

By the way, I´m using a switch to arm/disarm motors (Switch A on Radiolink AT9)
I was just wondering if that could be a setting or something that prevents this crap to happen again : but I don´t think so.

From what you say, I agree that it's not the motor screws or a short circuit problem.

Although 5030 props on these motors with a 3S battery won't draw more than around 5A, the ESCs you have now don't even run BLHeli (despite what the sticker says), so they won't have some of the safety features that modern ESCs have.

I don't know how much your quad, including battery weighs, but you won't actually get much thrust with this combination of motors and props on 3S. If it's underpowered, then it won't fly very well. How high does your throttle have to be just to hover?

(02-May-2017, 07:24 AM)unseen Wrote: From what you say, I agree that it's not the motor screws or a short circuit problem.

Although 5030 props on these motors with a 3S battery won't draw more than around 5A, the ESCs you have now don't even run BLHeli (despite what the sticker says), so they won't have some of the safety features that modern ESCs have.

I don't know how much your quad, including battery weighs, but you won't actually get much thrust with this combination of motors and props on 3S. If it's underpowered, then it won't fly very well. How high does your throttle have to be just to hover?

A little below the middle, like 1400/1450 I would say.
Could you please suggest a different setup for this ?
- Smaller props (4'') ?
- Different ESC ? (I´ve ordered these: https://www.aliexpress.com/item/Hot-FVT-...0.0.iLVSCA but it will take 60 days to get in Brazil)

Thanks,

(04-May-2017, 03:43 AM)flabombarda Wrote: A little below the middle, like 1400/1450 I would say.
Could you please suggest a different setup for this ?
- Smaller props (4'') ?
- Different ESC ? (I´ve ordered these: https://www.aliexpress.com/item/Hot-FVT-...0.0.iLVSCA but it will take 60 days to get in Brazil)

Thanks,

If you can hover at 50% throttle or less, then there is enough power to fly. Smaller props will reduce your power output and larger props will be too much for your current 12A ESCs. The new ones will allow you to use more aggressive 5" props like 5045 bullnose designs and also let you use 4S power instead of 3S.

Although you can use the EMax 2204 2300kv motors on 4S with 5045BN props, such a configuration is on the edge of what the motors will take.