How did I let the magic smoke out.

[4U2NVME]

Hey everybody,

Finally gotten a chance to get back to flying, been a busy spring and summer. I built the FT Cub and had some issues with the ESC. So I changed it out to an eMAX BLHeli 30A LiPo 2s - 4s ESC.

The issues I had with my ESC went away when I changed it...or at least for a while. My last flight I hand launched the plane, and the prop sounded a bit weird so I brought it in for a landing and made sure my prop was on strait ( I use a prop saver ) It seemed to be so I tried to launch it, and the prop did not really start up, it chattered a bit as if it was having a hard time starting, then all of a sudden magic smoke came out. I thought my battery was on fire so was not sure what to do right away, I did flip the plane over and saw the LiPO was not on fire so I unplugged it from the ESC

I did the throttle reset when I added the new ESC.. This is my third ESC that has crapped out on me in one way or another... this was just the fastest and most spectacular

I did check the battery right away with my battery checker and all 3 cells were within a very small amount of volts of each other, and it was still over 90%. I am using my original motor that seems to be working correctly...

What I am using:

BLHeli 30A ESP LiPo 2 - 4 S
Venom Drone battery 1350 mAh 30 C Lipo battery
9 * 4.7 slow fly prop
A 2212 / 10T 1400 KV electric motor

I have attached some pictures of the carnage, I am not sure what I did wrong, any help be appreciated.

-NV

 

[DamoRC]

It's possible that you are running the motor too hard. Do you have a link to where you got the motor? From what I have tried to find out about the motor based on the pics and it may be pulling too many amps on 3S with a 9 inch prop (although I personally would think that you are not too far over the spec on this).

Do you have a wattmeter? Do you know how many amps it was pulling?

DamoRC

 

[4U2NVME]

It's possible that you are running the motor too hard. Do you have a link to where you got the motor? From what I have tried to find out about the motor based on the pics and it may be pulling too many amps on 3S with a 9 inch prop (although I personally would think that you are not too far over the spec on this).

Do you have a wattmeter? Do you know how many amps it was pulling?

DamoRC

https://www.amazon.ca/gp/product/B01ALESI1C/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Hello here are the specs on this motor:

I don't have an wattmeter at this time

Dimart A2212 Kv1400 Brushless Motor For Rc Multirotor Aircraft Model Airplane Hobby

Description
Size: 27.8*27mm
Shaft: 3.17mm
RPM/V: KV1400
TEST DATA:
GWS1047RS propeller
Volt: 8V 7V
Current: 18A 15.1A
RPM: 6380 5860
Thrust: 775g 650g
GWS1060HD propeller
Volt: 8V 7V
Current: 15.2A 12.7A
RPM: 7220 6560
Thrust: 670g 553g
GWS9050HD propeller
Volt: 11V 10V
Current: 18.9A 15.4A
RPM: 9720 9240
Thrust: 903g 816g
GWS8040HD propeller
Volt: 11V 10V
Current: 12.6A 11A
RPM: 11800 11000
Thrust: 700g 606g
Notice
Due to the lighting effects and computer monitor resolution setting etc£¬the color tone of the photo could be slightly different from the real item.
Package Includes
1* A2212 KV1400 Brushless Motor

• Product Name: Brushless Motor A2212/10 1000KV
• Current Capacity: 12A/60s, No Load Current: 10V: 0.5A
• Max Efficiency: 80%, Max Efficiency Current: 4-10A (>75%)
• Number Of Cells: 2-3 Li-Poly
• Suitable for RC helicopter, airplane, quadcopter and multi-copter

 

[4U2NVME]

Here are two other motor choices I have in my inventory... I don't think I am ready for the 2300KV motor and a smaller prop yet.. I don't have the control on my plane yet...

https://www.amazon.com/gp/product/B00H8P50KU/?tag=lstir-20

https://www.amazon.com/gp/product/B01KFD3WBU/?tag=lstir-20

Who knew you could turn a trainer into a missile by running a 2300KV motor on a FT simple trainer lol

 

[Bricks]

When looking at the specs for the motor it mentions 8-10 volts not 12+ like a Lipo battery would have. Just shooting in the dark here you mentioned you burned up 3 ESC`s was this with the same motor? Does not seem logical that running the motor on 12+ volts versus 11 volts would actually burn up the ESC unless something in the motor is bad.

 

[cranialrectosis]

it chattered a bit as if it was having a hard time starting

This makes me wonder if you had a loose solder joint. Bad connections between the ESC and motor often cause the motor to "jitter". If you throttle up a jittery motor sometimes the motor or ESC smoke.

Your motor appears to be a Suppo 1400. I have used a ton of Suppo 1450s on 3S with 8045 props on 22A ESCs with no issues on (old school) quadcopters (BatBones, Knuckle H Quad and Anycopters). However in these cases my ESC is exposed to propwash in the open air.

Is it possible your ESC is overheating due to ventilation issues in the plane? Any idea how hot it got?

 

[4U2NVME]

Hi Bricks, yes it has been the same motor... I see the other one I have is a bit better ( take more amperage through it )

 

[4U2NVME]

....
Is it possible your ESC is overheating due to ventilation issues in the plane? Any idea how hot it got?

It could be vent issues, but this is a FT design... I assume they build them to account for this??

 

[4U2NVME]

When looking at the specs for the motor it mentions 8-10 volts not 12+ like a Lipo battery would have. Just shooting in the dark here you mentioned you burned up 3 ESC`s was this with the same motor? Does not seem logical that running the motor on 12+ volts versus 11 volts would actually burn up the ESC unless something in the motor is bad.

This was the only one I actually caught on fire....
My other ESC's one stoped beeping when I connected a battery to it...
The other ESC had issues where the motor would not run ( that jerking sound and action of the prop ) I tried to adjust the timings on the ESC from low to med to high... that did not fix it.
This one went poof.. so may be try a different Motor and ESC ( obviously lol )?

I thought I sized it correctly... between prop, motor, esc and Lipo battery.. did I get something there wrong? I'll check the 10V thing you saw in the specs... but I think it was a 2 - 3 S lipo electric motor... i"ll to re-review now.

 

[4U2NVME]

When looking at the specs for the motor it mentions 8-10 volts not 12+ like a Lipo battery would have. Just shooting in the dark here you mentioned you burned up 3 ESC`s was this with the same motor? Does not seem logical that running the motor on 12+ volts versus 11 volts would actually burn up the ESC unless something in the motor is bad.

If I changed to the other motor, the A2212 Kv1400 to the 2822 1200k from the I assume I lose some power/thrust because of the 400(2s) - 600(2) less rpm on the motor.. any other characteristic changes I would notice/see....besides maybe not lighting it on fire?

 

[cranialrectosis]

The 2822 1200 will probably handle a ton more power and produce more torque than a 2212 1400. Take advantage of the extra power by spinning a longer prop. Longer props are more power efficient and may increase your flight time.

Definitely check your specs to be sure.

Are you doing your own soldering?

 

[4U2NVME]

The 2822 1200 will probably handle a ton more power and produce more torque than a 2212 1400. Take advantage of the extra power by spinning a longer prop. Longer props are more power efficient and may increase your flight time.

Definitely check your specs to be sure.

Are you doing your own soldering?

Yes I am doing my own soldering...is that where you may be leaning towards as well? I do have a 10 X 4.5 prop.. that would not put to much load on that motor?

 

[cranialrectosis]

1* A2212 KV1400 Brushless Motor

• Product Name: Brushless Motor A2212/10 1000KV

I am having some trouble figuring out what motor you have. Is it a 1000kv or a 1400kv?

You can probably get away with a 1045 prop on a 1000kv motor on 3S. At 1400kv you will be a lot hotter and closer to specs and probably need to think 8045 on 3S.

I ask about soldering because of how you described your motor earlier. When I build a copter and have a "jittery" motor, it is usually because I have a cold solder joint. I have smoked an ESC and motor in the past by throttling up a "jittery" motor. A quick re-heat with my soldering iron to get the connection I want fixes the problem.

I don't know that this device would have helped you on the last ESC but whenever I use a soldering iron, when I first connect power, I use a smokestopper to prevent mistakes from being expensive.

 

[4U2NVME]

I am having some trouble figuring out what motor you have. Is it a 1000kv or a 1400kv?

You can probably get away with a 1045 prop on a 1000kv motor on 3S. At 1400kv you will be a lot hotter and closer to specs and probably need to think 8045 on 3S.

I ask about soldering because of how you described your motor earlier. When I build a copter and have a "jittery" motor, it is usually because I have a cold solder joint. I have smoked an ESC and motor in the past by throttling up a "jittery" motor. A quick re-heat with my soldering iron to get the connection I want fixes the problem.

I don't know that this device would have helped you on the last ESC but whenever I use a soldering iron, when I first connect power, I use a smokestopper to prevent mistakes from being expensive.

Thank you!! I will look at the smoke stopper... gotta keep the magic smoke in my electronics...

As for the Motor I have 3 I can use... I have:

1) A 2212 / 10T 1400 KV electric motor ( this is the one that I smoked my ESC with and appears the product page says both 1000 and 1400 km. Sticker on motor is 1400)
2) Emax Cf2822 1200kv ( one that is being suggested to put a larger prop on )
3) LHI DX2205 2300KV RC Brushless Motor ( which I don't 'think' is appropriate for the FT Cub build? )

-NV

 

[sprzout]

I"m assuming that your motor is a Suppo or Suppo knockoff, which is a 2212/10 with 180W limit, and weighs in at 47g. If I'm right, that motor's not meant for that big a prop!

Ran some bench tests through ECalc, and most models of 2212/10 motors are under 200W. Running the 30A ESC and battery is fine, but 9 x 4.7 slow fly prop is using approximately 233W of power in that combination. No surprise you're burning stuff up. The 1400 kv motor is meant more for something like a 6" prop.

Now, again, this is bench testing through a calculator, but it's fairly accurate when I've tested the same setups with a watt meter inline.

 

[sprzout]

Thank you!! I will look at the smoke stopper... gotta keep the magic smoke in my electronics...

As for the Motor I have 3 I can use... I have:

1) A 2212 / 10T 1400 KV electric motor ( this is the one that I smoked my ESC with )
2) Emax Cf2822 1200kv ( one that is being suggested to put a larger prop on )
3) LHI DX2205 2300KV RC Brushless Motor ( which I don't 'think' is appropriate for the FT Cub build? )

-NV

Of those 3, run through ECalc (https://ecalc.ch), the EMAX CF2822 is the one you want with that 9 x 4.7 SF prop...146 W/lb, approx. 9 min. worth of flight time on that battery; I think you'll find it working out for you.

 

[4U2NVME]

Thank you Sprzout, .... if I learn to use that calculator, may be I have better luck in the future. Right now I don't have anybody to fly with or learn from, its really been via the forums here and on FT videos. I'll have to watch a youtube video or two on it..many settings are required

https://ecalc.ch/motorcalc.php

 

[sprzout]

Thank you Sprzout, can you send me the link for the calculator.... if I learn to use that, may be I have better luck in the future. Right now I don't have anybody to fly with or learn from, its really been via the forums here and on FT videos.

Included in my previous post. It's a subscription based fee, and they have multiple different sites for things like multirotors and ducted fans and helicopters and such; however, I've not messed with a lot of the others, just the airplane one. And for that, it's $6.50 US for a year - WELL worth the cost.

 

[cranialrectosis]

I'm with @sprzout. I think you have a Suppo or Suppo knock off. If that's a 1400kv don't run a 1045 prop on 3S.

The 1200 might be able to handle a 1045 prop but a 0947 prop is more reasonable.

The 2205 2300 would make a rockin' Tiny Trainer on 3S with a 6045 prop.

The TT is VERY forgiving. My first was as crooked as a politician but flew great. If you need to relax a hot glue joint to release a missplaced servo, use a hot air gun or blow dryer (gently) to soften up the glue. Take care not to melt foam or strip the paper off the foamboard with too much air.

 

[d8veh]

I have attached some pictures of the carnage, I am not sure what I did wrong, any help be appreciated.

-NV

You must never try and run a motor when it's not working properly. By properly, I mean with normal noise, normal throttle response and normal speed.

These motors are three-phase and they need all phases working equally. You had a minor problem, like a faulty connection, which stopped the motor running properly, but even though the motor isn't giving out much power, full power is still going into it. That power can't give motion, so instead, it gives heat, which burns the motor in a short time, and can also burn the ESC at the same time

If at any time your motor stutters, growls, twitches or makes a grating noise, you mustn't give it anything more than enough throttle to test whether it's fixed. Instead, you need to find out why it behaves like that before you attempt a flight.