esc/bec problem
 

Hi all, I thought I would post this here because of the type of brushless ESC I'm using. It's a 60A Sky-Wing with external BEC. I'm running it in a 78" powered gluider with a little outrunner that only pulls about 20 amps max, a 3s LiPo and full size reciever with 2 standard sized servos. The problem is the BEC gets very warm and seems to shut down the receiver sometimes. I flew it yesterday for the first time and narrowly avoided a bad crash. Also the rudder servo is very glitchey. Any advice/info would be welcome.

RE: esc/bec problem
 

I would first check to see if your battery is sufficent for the motor draw. It could be the motor is drawing down the pack enough that the esc is sensing a low volt condition and is trying to shut down.

If the bec is getting hot, either you don't have enough airflow over it, or your servos are pulling the max the bec is rated for.

As for the glitching servo, could be quite a few things. Like a defective servo, which may be contributing to problem above. Try swaping the servos around to see if it's a bad servo or a channel related problem.

Rx interference, antenna running to close to the servo/esc/bec/motor wires.

Any carbon fiber in the plane? Can cause interference problems too.

RE: esc/bec problem
 

Thanks for the suggestions.

I'll check the draw but the pack was fresh and I used the same motor/prop with a 25A ESC and had no problems. Also, the entire receiver is losing power (no flight controls) so I think low pack voltage cutoff can be eliminated (I was also gluiding motor off the first time it happened).

The BEC gets very hot after the pack is plugged in for a few minutes (motor off). I'm only running 2 servos but they are the big ones and the glitching one is very active. It really seems like a thermal overload switch. I don't know anything about this ESC, I got it cheap from Ebay. Here is the link. [link=http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=320289475802]ESC[/link]

I tried switching the elevator and rudder servos and the problem moved to the elevator. I also tried connecting the rudder servo to the aileron channel and it glitched bad there too. Do you think the glitching might cause the BEC overload?

I tried moving wires/components around and sometimes find a spot that is glitch free but doesn't last long and a tiny shift will start it again. I just replaced the brushed motor and ESC that I had been using without any glitching problems. I'll try hooking it back up to check.

No carbon fiber.

RE: esc/bec problem
 

I just tried another receiver from one of my parkfilers and it flicked the servos and stopped working. I then checked the voltage from the BEC and it showed 10v! Gotta love the cheap parts.
Now I need a new receiver too.[&o]

RE: esc/bec problem
 

For INEXPENSIVE ESCs, I have had very good luck with TowerPro, Turnigy and Tuborix brands.
I strongly suggest running the other way as fast as you can if it is a "Mystery" brand ESC.
I tried one Mystery ESC (80 amp).
The initial one was DOA, (warranty return) the 2nd shorted out about 5 seconds after the battery was connected (warranty return) and the 3rd one shorted out about 10 seconds after connecting the battery (garbage can and wrote it up to a learning experience).

I usually use a 60amp ESC, 4s 4400 lipo and a 700 watt motor (TowerPro 3520 or similar in a Turnigy) with a 12x10 or 13x8 prop for my 40 size conversions.

I have found this combo works very well.

RE: esc/bec problem
 

Use A Castle Creation Bec $24 Bucks.