Scorpion 2216-12 + Stock ESC

[xatrix]

I just thought of something while reading the trex 450 forum.. people are getting 55-60A ESC for their helis..

I am running the stock 25A esc..

For how long can I get away with running the 2216-12 scorpion with the following specs:

Motor Kv 3350 RPM / Volt No-Load Current (Io) 1.87A @ 10V Amps Motor Resistance (Rm) 0.033 Ohms Max Continuous Current 35 Amps Max Continuous Power 375 Watts

together with my stock ESC. Using pitch curves and would assume around 2000-2100 RPM at hover/FF. Using an external BEC, so the ESC feels not as warm to the touch as it did with stock motor w/o BEC.

[Tail boom]

Originally Posted by xatrix

I just thought of something while reading the trex 450 forum.. people are getting 55-60A ESC for their helis..

I am running the stock 25A esc..

For how long can I get away with running the 2216-12 scorpion with the following specs:

Motor Kv 3350 RPM / Volt No-Load Current (Io) 1.87A @ 10V Amps Motor Resistance (Rm) 0.033 Ohms Max Continuous Current 35 Amps Max Continuous Power 375 Watts

together with my stock ESC. Using pitch curves and would assume around 2000-2100 RPM at hover/FF. Using an external BEC, so the ESC feels not as warm to the touch as it did with stock motor w/o BEC.

Hi,

Take a look at this page from E-flite, and look for the motor EFLM1340DF (that should be close to the B400 stock one):
http://www.e-fliterc.com/Products/Motors.aspx

The continuous current is 25 Amps.

If the definition of continuous current of E-flite is equivalent to the max continuous current of the Scorpion, than it will look too bad for your stock ESC with the Scorpion motor you mentioned.

If the max. burst current of E-flite is equivalent to the max continuous current of the Scorpion, than the stock ESC might be ok (I would NOT use it though).



Best,
Frank

[xatrix]

Thanks! been looking for that datasheet..

Now I'm wondering the difference between these:

http://www.readyheli.com/Scorpion_6_...p/sw45aesc.htm
http://www.readyheli.com/Scorpion_Co...com45a-esc.htm

Any difference other than switching BEC? I thought all the v2's had wireless programming cards? :O

[Tail boom]

Also, see here on the E-flite ducted fan motor version: They recommend a 25A-40A ESC. So the 25A stock ESC really is bare minimum!

http://www.rchobbiesandmore.com/prod...cat=315&page=1

[Swashmix]

Originally Posted by xatrix

I just thought of something while reading the trex 450 forum.. people are getting 55-60A ESC for their helis..

I am running the stock 25A esc..

For how long can I get away with running the 2216-12 scorpion with the following specs:

Motor Kv 3350 RPM / Volt No-Load Current (Io) 1.87A @ 10V Amps Motor Resistance (Rm) 0.033 Ohms Max Continuous Current 35 Amps Max Continuous Power 375 Watts

together with my stock ESC. Using pitch curves and would assume around 2000-2100 RPM at hover/FF. Using an external BEC, so the ESC feels not as warm to the touch as it did with stock motor w/o BEC.

You'll get away with it just with basis hovering and gentle flight. Once you start snapping it around, the stock ESC will eventually overheat and shut down.
BTW, I've the same motor in the mail. I will be using it with the Align BL35X.
Where did you get your pinion(s) from?

[xatrix]

Using a copterx pinion. Got it from Ehirobo.

CopterX (CX450-10-02) Motor Pinion Gear 11T/13T

2 pinions for 3 bucks. Not sure of the quality though..

[fishboy77]

I've been running the 2216-12 with the stock ESC for some 250 flights without issue. In fact, the ESC doesn't even get hot. And I am doing a good amount of fff and hard vertical punchouts.

http://www.youtube.com/watch?v=C8Xh0V2hi9o

The kv of this motor is only 3350 and I'm using a 10T pinion, so the headspeed stays pretty low, yielding a low current draw. Just because this motor CAN pull a lot of amps without frying doesn't mean that it will do so. Just don't overload it and you will be fine. Also, a switching BEC will help a lot with any heat issues.

[jmmccain]

Originally Posted by fishboy77

I've been running the 2216-12 with the stock ESC for some 250 flights without issue. In fact, the ESC doesn't even get hot. And I am doing a good amount of fff and hard vertical punchouts.

http://www.youtube.com/watch?v=C8Xh0V2hi9o

The kv of this motor is only 3350 and I'm using a 10T pinion, so the headspeed stays pretty low, yielding a low current draw. Just because this motor CAN pull a lot of amps without frying doesn't mean that it will do so. Just don't overload it and you will be fine. Also, a switching BEC will help a lot with any heat issues.

Yup. It's not the motor. It's the load on the motor. The stock ESC will be fine with this motor and:
10T w/100% throttle (2560 rpm, 13.3A, 112W output, just for fishboy77 )
11T w/100% throttle (2770 rpm, 16.3A, 141W output, less than stock)
12T w/93% throttle (2760 rpm, 17.5A, 140W output, % throttle chosen to match stock current below)
13T w/84% throttle (2670 rpm, 17.6A, 126W output, % throttle chosen to match stock current below)
14T w/76% throttle (2560 rpm, 17.5A, 112W output, % throttle chosen to match stock current below)

If you want to get the power out of that motor, then you might need to use a better ESC:
12T w/100% throttle (2950 rpm, 19.5A, 172W output, stock ESC fine in my opinion)
13T w/100% throttle (3130 rpm, 23.1A, 203W output, close call, are ya sport flying or hard 3D?)
14T w/100% throttle (3290 rpm, 27A, 236W output, recommend 30A+ ESC)

V-curve midpoints for "consistent" headspeeds:
12T 94% (2950 rpm)
13T 93% (3130 rpm)
14T 92% (3300 rpm)

Stock reference:
2850 rpm, 17.5A, 153W output

All the numbers above (except V-curve midpoints @ 0 deg. pitch) assume:
3s 20C 2100mAh battery
stock blade size
10 deg. applied pitch with developed flow (~6.7 deg. angle of attack)
external switching BEC (w/ 2A load @ 5.1V)

I don't know whether or not the stock head can handle the 13T and 14T speeds. Beware!

Regards,
Joseph

[MrCLoWnY]

I'm having a hard time mounting my Scorpion motor as the wiring gets in the way.... It seems like the wire should be somewhere else and wasn't meant to be fit in the Blade's frame.. Anyone else having this problem? Did it mount ok for you guys? It seems like once I get it in there, there is no way for me to adjust the mesh... :o

[Tail boom]

Originally Posted by jmmccain

Yup. It's not the motor. It's the load on the motor. The stock ESC will be fine with this motor and:
10T w/100% throttle (2560 rpm, 13.3A, 112W output, just for fishboy77 )
11T w/100% throttle (2770 rpm, 16.3A, 141W output, less than stock)
12T w/93% throttle (2760 rpm, 17.5A, 140W output, % throttle chosen to match stock current below)
13T w/84% throttle (2670 rpm, 17.6A, 126W output, % throttle chosen to match stock current below)
14T w/76% throttle (2560 rpm, 17.5A, 112W output, % throttle chosen to match stock current below)

If you want to get the power out of that motor, then you might need to use a better ESC:
12T w/100% throttle (2950 rpm, 19.5A, 172W output, stock ESC fine in my opinion)
13T w/100% throttle (3130 rpm, 23.1A, 203W output, close call, are ya sport flying or hard 3D?)
14T w/100% throttle (3290 rpm, 27A, 236W output, recommend 30A+ ESC)

V-curve midpoints for "consistent" headspeeds:
12T 94% (2950 rpm)
13T 93% (3130 rpm)
14T 92% (3300 rpm)

Stock reference:
2850 rpm, 17.5A, 153W output

All the numbers above (except V-curve midpoints @ 0 deg. pitch) assume:
3s 20C 2100mAh battery
stock blade size
10 deg. applied pitch with developed flow (~6.7 deg. angle of attack)
external switching BEC (w/ 2A load @ 5.1V)

I don't know whether or not the stock head can handle the 13T and 14T speeds. Beware!

Regards,
Joseph

Aaaah! I had waited for you to join this thread

Thank you,
Frank

[jmmccain]

Originally Posted by Tail boom

Aaaah! I had waited for you to join this thread

Thank you,
Frank

[fishboy77]

Originally Posted by MrCLoWnY

I'm having a hard time mounting my Scorpion motor as the wiring gets in the way.... It seems like the wire should be somewhere else and wasn't meant to be fit in the Blade's frame.. Anyone else having this problem? Did it mount ok for you guys? It seems like once I get it in there, there is no way for me to adjust the mesh... :o

I had no problem installing it - there's a fair amount of slide for mesh adjustment with a 10T pinion. In my setup I have the wires coming out of the motor on the right side of the heli and pointing towards the front.

[xatrix]

Mines the same. I can't really slide it.. Must be the pinion thats too big. But it works okay and I got longer flight times so I don't think its too tight.

[MrCLoWnY]

Thanks for the info.. I haven't put on my head yet to see how it spins, but i will give it a try..

But I still don't think it shold be this tight of a fit. ehehehe