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low esr CAPS
#1
i just put a REAL capacitor on, i had a radio shack 35v 470uf (m) series..and it worked fine.it stoped the problem i was having with freak outs and fail safes.....i was thinkin i would try a low esr..so i put a panasonic 35v 1000uf (fr) series from mouser electronics, and now after about 15 seconds of maneuvers or a flip, it fail safes... is the size of the CAP doing this, what i asking is, is the cap filling up then releasing energy over powering my 3s battery....im only running a 3s on this one, and 2600kv emax red bottoms.....
i have some smaller ones i could try out, but my goggle  fan switch went out so im kinda grounded for a few,...so i thought i would ask and get some thought before i just start in on the PART CHANGE and TEST again..

i did this to one of my other quads..but i put 4- 330uf 25v fr series on the esc, it made a HUGE difference in blackbox, and i could tell right away the sharper response due to cleaner signal..so this is why i thought maybe 1000uf and 35v is to big, if that a thing?lol
IF YOU AINT' CRASHIN' YOUR FLIN' TO HIGH!!
#2
1000uf 35v is what Oscar recommends for a 4-in-1 ESC, so I don't think that its the size of cap that's the problem.
Believe it or not, there was a thread a few months back, Oscar found a fake capacitor, which had a different cap inside the housing of a low ESR Panasonic! Did you get the cap from a reputable supplier?
Windless fields and smokeless builds
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#3
(14-Jan-2018, 05:10 AM)Tom BD Bad Wrote: 1000uf 35v is what Oscar recommends for a 4-in-1 ESC, so I don't think that its the size of cap that's the problem.
Believe it or not, there was a thread a few months back, Oscar found a fake capacitor, which had a different cap inside the housing of a low ESR Panasonic! Did you get the cap from a reputable supplier?

where can i find that thread?
i bought them from Mouser Electronics, seemed legit....seemed to have the same web page set up to pick and choose as the site bardwell recommended...maybe you could check out the site, see what you think...Mouser Electronics.

today i did some things...heres what i did....i put one Panasonic 330uf 25v (fr) on the front of the PDB on battery pads to the front escs, and i put one on the battery cable in the back of the PDB, i flew it...and now its fine...

would useing a 3s batery instead of the normal 4s make a difference?  1000uf 35v and 330uf 25v

i had a 470uf 35v (m) series NOT low esr radio shack special in place of the new 1000uf and it worked to stop the freak outs..but change this to a 1000uf 35v low esr and it seems like it loads up and then releases power and failsafes..i can fly around and do stuff but once i try a flip or fast maneuvers it failsafes... 

heres a crude drawing of the way i tryed, notice i moved the FC vbat to the 3s battery pads in the 1st pic...this might have been the problem the whole time, IDK..
the 1st one works and the 2nd one does not..but a 470uf 35v radio shack special works in the second drawing... 

IF YOU AINT' CRASHIN' YOUR FLIN' TO HIGH!!
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#4
1000uf on the main battery leads or on quads you can use 4- 470uf on each of the esc's
https://oscarliang.com/capacitors-mini-quad/
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#5
(15-Jan-2018, 01:59 AM)nitro20% Wrote: where can i find that thread?

I can't find it now, but the photo was hilarious, a button cap hidden inside the case of something else!

I have never used Mouser, but I have heard the name before, mentioned in a positive light I'm sure.

Realistically a 35v cap should be plenty for 4S, voltage spikes from a 5S might go over 35v though, but I think, too much voltage to a cap will pop it, rather than force it to discharge. (Correct me if I'm wrong?)

Remember that caps can start behaving badly before they are properly dead, you might just have a bad one?
Windless fields and smokeless builds
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#6
Maybe it's just one of your batteries going bad, or the batteries suffered from cold weather or something?

Essentially it sounds like your voltage drops off too much. The large cap might just make it more obvious maybe?
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#7
I seriously doubt a capacitor can cause failsafe to your quad, maybe something went wrong during the soldering of the cap?
By adding a cap your voltage will drop a tiny bit, but it's so small it's negligible to our quad. Not to mention we have a 5V BEC in place to power our RX in the FC.

i would recommend checking your soldering carefully, and make sure polarity is correct.
And lastly, if your quad ain't broken, don't try to "Fix" it Big Grin hehe
Don't be a LOS'er, be an FPV'er :) -- Blog - Facebook - Instagram - Twitter - Google Plus
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#8
(15-Jan-2018, 10:40 AM)Tom BD Bad Wrote: I can't find it now, but the photo was hilarious, a button cap hidden inside the case of something else!

I have never used Mouser, but I have heard the name before, mentioned in a positive light I'm sure.

Realistically a 35v cap should be plenty for 4S, voltage spikes from a 5S might go over 35v though, but I think, too much voltage to a cap will pop it, rather than force it to discharge. (Correct me if I'm wrong?)

Remember that caps can start behaving badly before they are properly dead, you might just have a bad one?


i dont get stuff to say what i want them to mean sometimes.lol.......what i ment was, i am useing a 3s batery now.i i have always flown 3s....so i was wondering if that would be the case..
IF YOU AINT' CRASHIN' YOUR FLIN' TO HIGH!!
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#9
(Yesterday, 12:26 PM)fftunes Wrote: Maybe it's just one of your batteries going bad, or the batteries suffered from cold weather or something?

Essentially it sounds like your voltage drops off too much. The large cap might just make it more obvious maybe?

yes this is it.....i think my 1550mah tattu 3s batteries are to small for this set up and the batteries do have about 50 cycles, they seem to have a good amount of fight time... the huge cap, small batteries and huge motors all i think play a part...

 the two 330uf 25 volts are working, and honestly i didnt see any difference between (m) and (FR) in the video, but i have a LC  filter in place too...i did see a huge difference in the BB data debug.....so much quieter..and it flew alot better, seemed tighter..

the FC is a flip32f4 w/mpu 20608 gyro so real noisy to begin with..i still wasnt satisfied and put a flip32 f4 v2.5 6000 gyro, and now i think this will solve my anal retentive shit i have going on...untill betaflight 32/32/32 came out 2 days ago...OMG here we go again....

NOTE: i am flying, i have others that fly great..im just messing around with this one, try stuff here try stuff there, just to see what i can do no my next build...
IF YOU AINT' CRASHIN' YOUR FLIN' TO HIGH!!
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