Think I let the magic smoke out!?!😫

[Paul Taylor]

I went to Maiden my new plane today. I’m not real sure what happen, but I think maybe the wet grass grabbed the wheel pants. The plane nosed over and the prop stopped on the ground, the plane tipped back down and started to roll out again only to nose over stopping the prop again. This time the pit man grabbed the plane and a big puff of smoke exited the cowl. It looked cool but had that bad electric smell. 😩

Setup:
Cobra motor
BA ESC

Question: should the ESC have shut down after the first prop strike?

PS the wheel pants are coming off. 🤬

[Dave Rigotti]

BEST to ask the folks at Bad Ass this question.

[Carl Cisneros]

what timer were you using?

Hubin timers do not have shut down in case of a prop strike

KR timers do have that function in case of a pop strike.

ask me how I know.

 carl

[Crist Rigotti]

What was the over current setting?

[Frank Donnelly]

I don't see current limiting as a programable feature in the BA ESC manuals. As previously mentioned it would be best to check with the Inov8tive Designs. The Castle Phoenix Edge ESCs have a current limiting function. Also as previously mentioned the KR timer monitors the RPM and will shutdown if there is a prop strike. Hopefully the ESC was the only thing damaged.

[Paul Taylor]

Called and spoke with the owner of BA. The ESC does not shut down for a prop strike. He said the new versions will have that feature. He said the Cobra and Tempest ESC’s did have that feature. I think I will be switching brands.
I just cooked a brand new motor. 🤬

[Ken Culbertson]

That is such a basic function that I am surprised, this many years into electric, that every timer/esc marketed to the CL world doesn't have it.  I may be underestimating the complexity, but it seems like one line of code in the right place could trigger a shutdown. "if runtime > 2 and RPM < 50 then 'kill_it".  That is a legitimate line of code in Basic.  I am sure whatever language the timer/esc folks use has something similar.  Time to turn it on and minimum RPM can easily be stored parameters.

Ken

[Brent Williams]

Here's your chance to use a Castle Edge-Lite or Talon ESC.  You will get the over-current protection and gain the Hi-Governor function vs your existing Badass esc. 

[Crist Rigotti]

Here's your chance to use a Castle Edge-Lite or Talon ESC.  You will get the over-current protection and gain the Hi-Governor function vs your existing Badass esc.

What Brent said!

[Shorts,David]

My first castle did the same thing and puffed smoke because I hadn't program ed the high voltage spike cutoff. Easy fix, but costly lesson.

[Paul Taylor]

Here's your chance to use a Castle Edge-Lite or Talon ESC.  You will get the over-current protection and gain the Hi-Governor function vs your existing Badass esc.

Thanks Brent

I am using 4s batteries. I don’t see a Edge-Lite that goes that small. I did see a Talon that is 4s.
What would you recommend?

[Brent Williams]

Thanks Brent

I am using 4s batteries. I don’t see a Edge-Lite that goes that small. I did see a Talon that is 4s.
What would you recommend?

I have a Cobra 2820 970kv, Castle Edge-Lite 50 ESC and Hubin FM-9 in High Governor mode, Thunder Power 4s2800, BadAss 11x6 wood prop. It only pulls 28amps holding on the ground at 9908 rpm.  (Hubin programmer box RPM setting) The attached picture shows the amp draw of this setup, running on the ground.

It's much more about amp draw, not necessarily number of cells in the selection of your ESC needs.  Each of the Castle ESC'S mentioned can handle 6 cells or more.
All of the Castle ESC's can be adjusted in the Castle-Link program to shut down as low as the stated amp rating of the ESC, i.e.  35, 50, 60 amps.  It's not as fool proof as a stopped rotor/prop function, but it should save itself from a meltdown in case of a nose over or similar event.

Talon 35 would probably cover my current needs and is lighter at only 1oz.

Edge Lite 50 if you want to data-log, and need that extra amp capacity. (2oz)
(I have run this same Edge-Lite 50 ESC on 6S TP2800 with a Cobra 3520 700kv motor & 12x6APC)

Talon 60, no data logging and is ready for any higher amp draw needs. (2oz)

[Air Ministry .]

Instaation data .

http://www.whereisbobl.com/tiger/smoke.html

[Paul Taylor]

I have a Cobra 2820 970kv, Castle Edge-Lite 50 ESC and Hubin FM-9 in High Governor mode, Thunder Power 4s2800, BadAss 11x6 wood prop. It only pulls 28amps holding on the ground at 9908 rpm.  (Hubin programmer box RPM setting) The attached picture shows the amp draw of this setup, running on the ground.

It's much more about amp draw, not necessarily number of cells in the selection of your ESC needs.  Each of the Castle ESC'S mentioned can handle 6 cells or more.
All of the Castle ESC's can be adjusted in the Castle-Link program to shut down as low as the stated amp rating of the ESC, i.e.  35, 50, 60 amps.  It's not as fool proof as a stopped rotor/prop function, but it should save itself from a meltdown in case of a nose over or similar event.

Talon 35 would probably cover my current needs and is lighter at only 1oz.

Edge Lite 50 if you want to data-log, and need that extra amp capacity. (2oz)
(I have run this same Edge-Lite 50 ESC on 6S TP2800 with a Cobra 3520 700kv motor & 12x6APC)

Talon 60, no data logging and is ready for any higher amp draw needs. (2oz)

Thanks! Great info.
Points to ponder

[redout]

Not my idea, but I have often wondered if a fast-blow fuse in one of the battery wires could prevent burning out an expensive motor.

[John Rist]

I have gone completely with the KR timers because it protects agents prop strikes and also it works with a cheep ESC.  However be aware that during the first seconds of runtime the KR is ramping the motor up to full speed.  It checks to make sure there is a good working motor and then throttles back to a set RPM level.  During this runup time it is not protecting agents a prop strike.  SO if you are using a stooge or a helper to launch all is good because you can hear the motor drop back to set rpm level.  If you are flying by your self and let the aircraft launch at the end of startup delay you have a second or two of variability.  I fly on pavement so a noise over on takeoff is rare. So far with the KR timers I have not burnt out a motor or speed controller.  PS I have burnt out motors but that was my fault.  I found out the hard way that you can't run a setup on the ground for a long period of time with a full size prop.  Motor unloads and current draw goes down when the airplane launches.   

[Dan McEntee]

Not my idea, but I have often wondered if a fast-blow fuse in one of the battery wires could prevent burning out an expensive motor.

      Back in my R/C sailplane days, that is exactly what we did. Motor control was mostly a simple on/off with a servo arm tripping a micro switch. There were some on/off electronic motor controls then. Simple enough because all we wanted was a good, fast climb out to altitude, maybe two, then shut down. Folding props were scarce and expensive, so to stop the prop in a specific horizontal position. I had a short length of plastic rod from a push rod set that would stop the prop where I wanted it. So to protect the motor and battery, we had as small a fuse as we could find, and also an arming plug to prevent accidental start ups.
 
   Type at you later,
     Dan McEntee

[John Rist]

Not my idea, but I have often wondered if a fast-blow fuse in one of the battery wires could prevent burning out an expensive motor.

It's tricky to get the fuse the right size.  Too big and it does no good. too small and it may trip at the wrong time.  Also fuses have resistance and therefore burn some power.  Added to all this it adds solder joints and weight.  This and many other reasons very few if anybody has a fuse in a stunt ship setup.  A much better solution is a KR timer or an ESC that has over current shutoff built in.   

[Keith Renecle]

John is correct in saying about my timers only shut down once the governor mode has kicked in, because my program needs to start measuring rpm in a stable mode. Therefore the model needs to be held on "not-so-great" grass until the rpm is high. It's not easy to shut down the motor on high current because the spikes in the hard corners are already high, so monitoring a sudden drop in the rpm is a good way that works very well. A fuse would be too slow to react.

If the grass is rough, then use a helper and just wait for the rpm to kick in. Use a stooge if flying alone anyway, to avoid the model deciding to take off while you're walking out to the handle. A simple stooge is easy to make for a grass field.

Keith R