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Old Jul 23, 2006, 09:29 AM
Hold my beer and watch this!
Jeremy Z's Avatar
Northern IL
Joined Oct 2005
2,380 Posts
Avoid the cheap E-Flite brushless ESCs...

I finished the AM yesterday.

I was setting up the controls, and everything was going fine. Slowly, but fine.

I had just finished reversing the channel to get the rudder moving the right way, and I accidentally bumped the throttle stick. (the prop was on) I was smart enough to stay clear of the prop, but not smart enough to remove it. (I had just balanced the plane, so it was still on)

The prop made a half-turn and jammed against the carpet. I cut the throttle right away. Naturally, the throttle didn't work after that. I thought: "No problem, I'll just reset the input power and I'll be good to go..." No such luck. I tried it again after 30 seconds, thinking I would let the caps bleed down. No luck. I sniffed the rudder servo, as it was buzzing. No problem there. I sniffed inside the fuselage and smelled burnt semiconductors. (I know this smell from work) I knew what it had to be, and after I removed the battery, my worst fears were confirmed.

The heatshrink on the ESC was split open, and four of the surface-mount chips were blown.

Silly me for leaving the prop on during programming, and silly me for bumping the throttle stick. But shouldn't all ESCs have electronic overcurrent protection built in? Has anyone else had this happen with another type of ESC? I have a Castle Creations Thunderbird 18 that gets locked up once in a while on my EasyGlider because it "forgets" where the throttle off position is once in a while, but the motor stays locked for a couple seconds, and the ESC shuts down. If I reset the input power, it works again.

It hurts to be out $55 of the cheap ESC (E-Flite 40 A brushless) but I want to make sure the next one I buy will not have this problem.
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Old Jul 23, 2006, 09:30 AM
Hold my beer and watch this!
Jeremy Z's Avatar
Northern IL
Joined Oct 2005
2,380 Posts
I wonder if an overloaded BEC contributed? 2 HS-81s and 2 HS-55s was probably pushing it. Are you all using BECs with 3S? What controllers are you using with your 350-375W motors? (I didn't want to pay the $90 or whatever for the Phoenix...)
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Old Jul 23, 2006, 09:32 AM
Hold my beer and watch this!
Jeremy Z's Avatar
Northern IL
Joined Oct 2005
2,380 Posts
Pjtorr, the buzzing sound I mentioned from this plane is because everything is mounted so solidly to the fuselage. This is going to rattle screws loose over time, so watch out for this people! (yes, I balanced my prop)
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Old Jul 23, 2006, 10:58 AM
Me likes Depron...
Pjotrrr's Avatar
Amsterdam Schiphol, Netherlands
Joined Mar 2003
1,577 Posts
Hi Jeremy,

The Kontronik Jazz controllers have a "switching" BEC, even at 5slipo this BEC delivers a steady 3A...
the new line from YGE, another German brand has got this too now, but the Chinese have made some cheap ones too, for about $50 you can buy them at www.himodel.com
Here in Holland www.rctechnics.nl sells the Himodel ESC's
I'm thinking of trying one of these too...

Peter
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Last edited by Pjotrrr; Jul 23, 2006 at 01:36 PM.
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Old Jul 23, 2006, 01:13 PM
Me likes Depron...
Pjotrrr's Avatar
Amsterdam Schiphol, Netherlands
Joined Mar 2003
1,577 Posts
Another nice vid:

http://airtoimedia.nl/web/upload/vdV...croMaster2.wmv

48Mb, but worth the wait...

Same setup as last video, but this time only 960 grams with Hyperion 3s1800

After this flight there was still juice left in these tiny lipo's for a minute or so...
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Last edited by Pjotrrr; Jul 23, 2006 at 01:28 PM.
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Old Jul 23, 2006, 01:39 PM
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charlatan's Avatar
Liverpool, UK
Joined Jun 2002
459 Posts
Maidened mine today. Well impressed, oodles of power. Unfortunately didn't get any video, it was blowing a hoolie on our field.

I am less impressed tho with the undercarriage. It gave me no end of problems, what with wheel collets coming loose and the wheels coming off. Other than that well happy, my Magister, Funjet and Acromaster all returned from the field in the same condition they left the house in
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Old Jul 23, 2006, 05:13 PM
Registered User
Belgium
Joined Apr 2006
106 Posts
Great Video Peter

I'm amazed what one can draw out of a 1800 battery.
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Old Jul 23, 2006, 06:01 PM
Registered User
Oxfordshire - UK
Joined Jan 2003
53 Posts
Found my USB lead - here is the UC mod I spoke about earlier

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Old Jul 23, 2006, 10:03 PM
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TexasFlyer's Avatar
Houston, TX
Joined Sep 2005
1,015 Posts
Zippo,

Thanks! A picture says a thousand words.

Alan
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Old Jul 23, 2006, 11:01 PM
Flyin' Ryan
USA, MO, Lee's Summit
Joined Sep 2001
980 Posts
Good to hear all of these AMs being readied for flight. I am still waiting for the motor (Eflight power10) and ESC (CC Phx45). They should be at the LHS early this week. My landing gear appears solid, but I haven't flown it yet. The Elapor wheels look like they are good for one touch and go, but I like the wheel pants. I have 2 polyquest 20c 1800s and 2 dualsky 2250 packs. I was planning on going 3s2p. I figured I would be pulling 30-35A, and don't trust most 20C ratings. How warm are those packs coming out of the AM?
I really like this planes size. It just seems like it ought to fly great.

I used the HS81's on rudder and elevator, and HS65's on aileron. I noticed (too late) the manual said the other way around, but they fit better the way I mounted them. The EZG uses the 81's on on R&E, 55's on ailerons (much smaller ailerons though), There is only a few oz diff in torque of the 81's and 65s. Will I be OK?


Ryan
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Old Jul 23, 2006, 11:05 PM
Flyin' Ryan
USA, MO, Lee's Summit
Joined Sep 2001
980 Posts
Jeremy, you may want to check out the ESCs from 2dogrc. They have a couple of inexpensive 40A+ models. They program with a Jeti card, so should be easy to setup. I haven't had any experience with them, but it might be worth a search.

Ryan
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Old Jul 23, 2006, 11:44 PM
Hold my beer and watch this!
Jeremy Z's Avatar
Northern IL
Joined Oct 2005
2,380 Posts
Quote:
Originally Posted by Pjotrrr
Hi Jeremy,

The Kontronik Jazz controllers have a "switching" BEC, even at 5slipo this BEC delivers a steady 3A...
the new line from YGE, another German brand has got this too now, but the Chinese have made some cheap ones too, for about $50 you can buy them at www.himodel.com
Here in Holland www.rctechnics.nl sells the Himodel ESC's
I'm thinking of trying one of these too...

Peter
Peter, thanks for that link. If the balancing series ESCs work as advertised, that might be the way to go. It looks like they have a tap for the Hyperion type balancing tap too....

I checked out the Kontronik Jazz 40A ESC:
http://www2.towerhobbies.com/cgi-bin...?&I=LXGCW2&P=7

Son of a B TCH are they ever proud of their product! $170 for an ESC? I don't care HOW good it is, it can't contain more than $20 worth of parts. I'll try the Chinese one when I get the $$ together again.

In switch-mode power supplies, "switch-mode" nearly always implies that the device has automatic overcurrent protection. Is it safe to make that assumption here?
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Old Jul 24, 2006, 04:35 AM
Me likes Depron...
Pjotrrr's Avatar
Amsterdam Schiphol, Netherlands
Joined Mar 2003
1,577 Posts
I don't really understand whay you mean, the switch mode BEC always keeps 5V/3A to the receiver, no matter how many lipo's are used in series (2 to 5slipo)
I wouldnot care for that balancing feature, I never have problems with my lipo's getting out of balance, charge and use them the right way and they last for long...
If you want to be sure with a pricy pack a balancer between pack and charger one in the ten times you charge them is safe enough...

The Hyperion 3s1800 was not hot at all after the seven (!) minute flight of the video...
So it's only 15A on average during the flight, this won't hurt these 20C packs at all...

My choice would be two of these packs instead of one 3s3200....
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Old Jul 24, 2006, 05:25 AM
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ModelTony's Avatar
Irvine, Scotland
Joined Jun 2004
636 Posts
Quote:
Originally Posted by Jeremy Z
Peter, thanks for that link. If the balancing series ESCs work as advertised, that might be the way to go. It looks like they have a tap for the Hyperion type balancing tap too....


In switch-mode power supplies, "switch-mode" nearly always implies that the device has automatic overcurrent protection. Is it safe to make that assumption here?
The purpose of tapping each of the cells is not for balancing, but so that the ESC will enter into cut-off mode when the first cell goes below the cut-off voltage.

Tony
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Old Jul 24, 2006, 07:54 AM
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LaMuse's Avatar
Austria - Vienna
Joined Jul 2005
92 Posts
Configuration

Hi all,

I am going to get my own Acromaster too very soon but I am still searching for the best configuration...
After having read lot of forums (and of course this thread), it seems that the Himax c3516-1130 with 45A ESC and 11x5,5 is very good.
I have read also of AXI 2820/10 or 12 (can't tell the difference!).

Anyway, my point is that my retailer, who i consider competent, is proposing following configuration:
- Brushless Pulsar BL25
- ESC Multicont BL27 (Multiplex)
- APC 10 x5
See the details

Well i must say that i am not convinced about it. What do you think ?
Does anyone have any experience of Pulsar motor ? Seems too weak to me compared with the Himax or Axi.
What about the ESC ? Isn't it too light (27A /35A max) ?

Thanks for your support!
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