Stock trex 470L failed BEC test?

In case you do not know something or you are not sure, here is the right place for your question.
HateTheDrake
Posts: 5
Joined: Sun 23. Jun 2019 23:45:37

So I had a weird crash recently where it became unresponsive. Others point to the stock 50a esc as being too weak.

Just to confirm: the esc needs to survive the BEC stress test which tries to simulate peak load, correct?

Mine, using the stock DS450M servos, logs low voltage and rx loss each time. I bumped esc voltage output to 8.5 and it now reboots towards the end of the test.
HateTheDrake
Posts: 5
Joined: Sun 23. Jun 2019 23:45:37

Also note: this is on a standard spirit with a single dsmx sat. The crash was on firmware 2.6.3 or 2.6.4. All the BEC tests were on 2.7.1.


Sent from my iPhone using Tapatalk
ZeXx86
Site Admin
Posts: 12836
Joined: Mon 29. Apr 2013 16:06:44
Contact:

Hello,

I am afraid you will have to add external capacitor to help the BEC or to lower the voltage. With higher voltage current is increasing actually causing bigger voltage drops.
It might work better with 6V but I recommend to add electrolytic capacitor of 2200 - 4700uF.
Spirit System developer
HateTheDrake
Posts: 5
Joined: Sun 23. Jun 2019 23:45:37

Thank you. I do plan to lower voltage back to the default of 6. I’m not familiar with adding a capacitor, will need to research.

Everyone keeps saying to get a new esc. (HW or castle)


Sent from my iPhone using Tapatalk
User avatar
urgno
Posts: 274
Joined: Tue 21. Aug 2018 13:05:23
Contact:

you can get something like this one
the higher the capacity the better
Image
HateTheDrake
Posts: 5
Joined: Sun 23. Jun 2019 23:45:37

Thanks guys!


Sent from my iPhone using Tapatalk
dub
Posts: 34
Joined: Thu 19. Jul 2018 13:54:36
Location: Litoměřice

r2-buf-325-rtf.png
Hi I have these capacitors and I am fully satisfied
Logo 700,T-Rex 500X Dominator, Spirit PRO, GeoLink, Jeti DC-24
User avatar
urgno
Posts: 274
Joined: Tue 21. Aug 2018 13:05:23
Contact:

R2 buffer is the Ferrari of the capacitors ;)
HateTheDrake
Posts: 5
Joined: Sun 23. Jun 2019 23:45:37

I put one of these on the BEC port and it passed many tests without errors or rx drop. ...even on 8v. I’m not sure what this is rated at, maybe 2474uF.

Thanks! [emoji106]

https://www.hobbyrecreationproducts.com ... -capacitor
User avatar
Genesis
Posts: 59
Joined: Thu 19. Jan 2017 2:17:34
Location: Alberta, Canada

urgno wrote:R2 buffer is the Ferrari of the capacitors ;)
Yes they sure are, too bad no one sells them anymore, at least not that I could find.
Blade 230 S / 230 S NF / 450X / 500X / 550X ~ Trex 470LM ~ OXY 3-285 / OXY 4-325 / OXY 4 MAX ~ Spektrum DX9 BE / DX6 Gen 2 ~ Spirit FBL
_______________________________________________
Team OXY Helicopter - Lynx Heli Innovations Field Rep
Post Reply