quad goes back down after throttle

Hoki

Member
Why does it do this!? I got a fully charged 5500mah 11.4 volt 3s battery under my s500 frame with a APM 2.8 and 30amp simonk escs. I have the failsafes off too. I have two batteries and it does the same thing on both. Could the battery just be under powered? I did get cheap 15 dollar floureon battires on gearbest but they are rated at 5500 30c 11.4 volts and I use a Imax b6 charger and it shows that it charges to capacity. Would it not be supplying the voltage it needs though? I do have a smaller gauge wire extention cable that goes to the xt60 plug on my frame to the battery. is that ok or should that 3 inch extension cable by the same gauge as the battery wires for its plug? Anyways, WHAT'S GOING ON. Before there was no foam inside the apm case so I put a big foamy foam inside it and it's covering everything and it didn't have any effect.
 

jbrumberg

Member
I am not familiar with the Imax B6 charger, but if your charger can do it, check the Internal resistance of those batteries. They may be starting to fail. IR normally goes up as batteries age and/or are abused by crash trauma, over-discharging, poor storage care, etc. Batteries that have high IR will take a full charge, discharge rapidly, and then go back to decent looking voltages with the battery's voltage rebound with cooling down. I would also check the individual cell voltages in each battery if you can. They should read similar voltages.

I do not think that using smaller gauge wire is a good thing, but I am no expert on this stuff.

Good luck.
 

Hoki

Member
wellllllllllllllllll I just found some wire in a box so I used it but it wasn't as thick as the one on the power plug of the battery. You think both my batteries could be no good? They are both pretty new, I never even been able to do a real flight with them. Just have them plugged in when I'm trying to get off the ground and doing tests. each cell does get the same number too. should I just get an expensive battery? I have smaller 2200 lips I use on other 250 size quads that work good. can I try one of those? do you think it'll have enough power for my 450 for at least a little while to test it?
 

jbrumberg

Member
If they are 3S LiPo's it would/could be a good test.

Your performance with those 5500mAh LiPo's is very similar to what happened to me with my aging and abused 3S 4000mAh 25/35C Zippy Compact LiPo's. Immediately after liftoff my low voltage alarm would start beeping. I would land and my voltages looked good per cell and total cell charge under "no load". I forget what the IR (Ohms) values were. With new batteries the problem disappeared.
 

Hoki

Member
FU@k ME! BUT THESE ARE NEW BATTERIES. I ORDRED THEM OFF GEARBEST, WHERE THE HELL DO I GET GOOD LIPOS FROM. HOLY CRAP STICKS
 

jbrumberg

Member
I have no complaints about HobbyKing(USA) for purchasing LiPo batteries and my choice of Zippy Compact LiPo batteries. I have read both + and - reviews about these batteries.

I think there are new postal and delivery service regulations for the transport of LiPo batteries in the USA.

I do not think "cheap" is really cheap in the long run when it comes to LiPo batteries , but I am no expert.

Some of the biggest killers of LiPos is to over-discharge, overcharge, and storage at full voltage for long periods. Physical trauma from "hard knocks" does not help. I have been guilty of poor LiPo management and storage and physical trauma in the past.
 

Hoki

Member
ok well I just ordered a 4s 6200 35c battery for 50 bucks! cause I was reading a bunch of crap online and it says you should get a 4s if you are using a 3s and won't hover at 50 present throttle cause on mine it will barely start to get off the ground like at 75 percent throttle and this article says a 4s will make motors spin faster too. So I'll see on the 12th when I get it in the mail! I'm so excited. If this was my problem all along I'm gonna die.
 



Hoki

Member
Ok so I just got home and I found a multitool and it said 12.5 on a full charge on the 3s 5500mah battery and then I tried to fly it and I needed like a bunch of trim to take off without wanting to tip but it took of so nice and flew nice for like 1 min and then beep beep beep beep beep beep then it started coming down then I throttled again and 10 secs later the beeps and it came back down. So I stuck those things in my battery again but this time it said 13.5! Wtf is going on. I expected it to say less than 12.5....
 

Hoki

Member
So I just put in the other newer fully charged 3s battery. Its the same kind just recently came in the mail and it flew good for MYBE 5min no beeps but it came back down and when I went bak up it came down agIn within a min. So weird. So do u think I just need a more powerful battery? I read so many posts where people r using 3s batteries with the s500 frame and 30 or 40amp escs. So why can't i
 

Alwil

Member
Make sure the wire to your power distribution board is the same size wire as on your
battery. It should not be smaller. Is the wire getting hot? How much does your copter
weigh?
 

Hoki

Member
My s500 frame has a built in distribution. No hot wires. I'll weight it in a bit I'm in the shower. But I think no more than 2lbs
 

Alwil

Member
I think I read where you made a 3 inch extension with a smaller wire. That is a no-no. That would be
like having a 4 inch water pipe reduced down to a 1 inch pipe. You will not get the flow.
It could very well be the batteries. You don't know how long these batteries have been
setting on a shelf before you bought them. Depends on the supplier and their honesty.
 

Hoki

Member
OK WELL I MADE ANOTHER EXTENTION THAT HAS A MALE XT60 ON ONE SIDE AND A FEMALE ON THE OTHER SIDE BUT THIS TIME I USED THE SAME GAUGE WIRE AS THE ONE ON THE BATTERY SO EVERYTHING IS NICE N THICK BUT IT DIDN'T DO A DAMN THING CAUSE WHEN I TEST FLEW IT IT STILL ACTED THE SAME WONKY WAY. So I'm really hoping this is a battery issue and for some odd reason I just need a 4s battery but I donno why in HELL I would NEED a 4s battery to make it fly right. It's not like I have odd components and I looked up my ESCs and they say 2s - 4s. I couldn't find much info on my powermax motors though. I've been readying that with 4s batteries it makes the copters a lot faster and harder to control and I soooo don't wanna deal with that but I'm thinking maybe it won't do that since I can't even lift off the ground good at all with the 3s maybe the 4s will feel just right? It will lift off and fly for a few min maybe on a 100 percent charge but as soon as it drops down even at 90 percent, it won't wanna lift off and many many times I can give it full throttle and it won't go up and when I check my battery it says it's at 80 or 90 percent still. Whyyyyyyyyyyyyyyy do I have such a weird copter? Is it my ESCs that are doing this? They are simonk 30 amp ones I hard ordered from aliexpress. I do have a set of 4 20 amp ones, should I use those instead? I'd freakin hate to swap them all out for the other ones and it didn't change anything.
 

Alwil

Member
I take it you programmed the esc and calibrated throttle range. Now is there something in
your flight controller that sets the voltage? I am not familiar with what you are using but
mine I have to tell it what voltage I am using. Your esc should be fine if they were calibrated.
 


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