Replies to This Discussion

DeveloperPermalink Reply by Randy on August 9, 2012 at 9:58am

You can test your APM2 by just powering it with your miniUSB cable connected to your PC...that'll allow you to test that it's ok (i.e. you can look in the MissionPlanner's flight data screen to ensure it's reacting normally).  You could then attach a small servo to the APM2's output rail (although you'd have to provide power to the rail somehow...perhaps by connecting the power from the input rail to the output rail).

 

A bit off topic but can I ask what ESCs you were using?  I use to use Hyperion ESCs but I found they were incredibly easy to short out and destroy.  They didn't seem to have any protection against this kind of accident.  I haven't had any such problems with either the jDrones or 3DR escs though.

Permalink Reply by Alexandre Nascimento on August 9, 2012 at 10:16am

Hi Randy, thanks for you help

It is possible put some jump from input to output? like put a wire from negative to negative and a positive to positive?

I have used the Turnigy AE-30A Brushless ESC (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=...)

DeveloperPermalink Reply by Randy on August 11, 2012 at 4:25am

Alexandre,

     ok, I would have thought those Turnigy would be as good as any..I've also used Turnigy's without issues although not that exact version.

     I'm probaly missing your point a bit and I'm not an expert on the hardware side but I believe it's possible to put current resistors in some places to protect against a short.  These heat up if the current going through them is too high, at the same time their resistance goes up to the point that they won't let any more current through for a while but you can't put them everywhere.

DeveloperPermalink Reply by R_Lefebvre on August 11, 2012 at 5:20am

I'm also not totally understanding what the issue is, how did it short out? Was it the power stage, or the controls stage of the ESC?

Anyway, I have one of these servo testers, and it's really handy.  It can drive servos (or ESC's directly), and it can also measure PWM input!  I actually use it for simple debugging of the system.

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=...

Permalink Reply by Redemptioner on January 6, 2013 at 7:09pm

Hey Alex,

I used these to start with, they have protection so if you connect the power the wrong way round they won't short out anything on the output from the BEC. In fact they will take a reverse polarity connection for a really short period of time (a few seconds) before the protections melts down and kills the input side of the ESC. I moved away from theses due to their update rate being too slow (only 160hz) and  ecause the BEC on these are really crap. The BEC in these things are really bad and are situated right on the end of the heatsink and aren’t as high as the rest of the “chips” under the heat sink, this means they don’t get much cooling. Don’t use the BEC on these as they burn out really quickly even under small loads, this also means that there continuous draw is greatly reduced and is really only like 1amp after a minute or so as they heat up. Unfortunately when the BEC fails it takes out the rest of the ESC (killed six  f 4 of them before I realised what was happening, I was only drawing 400 millamps but was running them for 30mins at a time). Just buy a decent 5amp SBEC as they are only like $6, they will give much cleaner and more reliable & consistent power (as your battery voltage drops the voltage output from these Linear BEC’s in this ESC also drops).

 

So your short may not be a short, it may be just the BEC dying and killing the ESC like it did for me, the last time it happened it took out 3 xESC's so I changed them all over to Simonk flashed FA-30's which you can by already flashed for a few dollars more than this ESC and has a refresh rate of 600hz.