Horrendous flight time!!

cliofreak

Member
Hey all, Im getting only 3min 30sec on a 5000mah 3s and only 2min 20sec on a 2200mah. My quad has Tarot gimbal, 28 26 1100KV motors and 8 inch plastic props. I have just bought FPV gear and I fear that extra weight will render the quad unless. Any ideas? The total weight with gimbal, gopro and 5000 3s is 1620g (3.57lb). Please help me figure out what to buy to fix this! Thanks.
 


Benjamin Kenobi

Easy? You call that easy?
Hey all, Im getting only 3min 30sec on a 5000mah 3s and only 2min 20sec on a 2200mah. My quad has Tarot gimbal, 28 26 1100KV motors and 8 inch plastic props. I have just bought FPV gear and I fear that extra weight will render the quad unless. Any ideas? The total weight with gimbal, gopro and 5000 3s is 1620g (3.57lb). Please help me figure out what to buy to fix this! Thanks.

How are you measuring flight time? How many mah are you putting back into your lipos? (think 20% rule).
 

cliofreak

Member
How are you measuring flight time? How many mah are you putting back into your lipos? (think 20% rule).


Hi, Im measuring with a stopwatch on my iPhone. I hover at about 40% maybe. Definitely not over 50%. Its got loads of power to lift. Im not sure what you mean about how much back in...if you mean charging then 12.6v is when the charger beeps.
 


Benjamin Kenobi

Easy? You call that easy?
Ah, sounds like you might be new to lipos?

If you are relying on the default voltage limits on your flight controller then these have a tendency to kick-in too soon. For a 3s lipo when the voltage gets down to around 11V it is probably about time to land. Depends on the voltage drop during flight though. 10.8V is probably normal.

Does your charger tell you how many amps you've put back into a lipo? That's what I mean by mah (milliamp hours). It's the best way to tell how long you can fly your lipos for.

What flight controller are you using?
 

cliofreak

Member
Well, I'm using a kk2.1
Ive got the board set to beep at 10.8 so its definitely using all the power. You mentioned amps. When I try to charge my 5000, the charger shuts off if I select anything more that 2.5A So, I just charge at 2.5. I though that was the rate but maybe its the amount of Amp going in as it charges for empty in less than an hour and id expect it to be 2 hrs!!
 


Benjamin Kenobi

Easy? You call that easy?
No, I don't mean the amps you charge it at. The lipo had 5000mah in it, that's it's capacity. There is a 20% rule for lipos where you should always leave 20% of the capacity in it to preserve the life of the lipo. For a 5000mah lipo you should put back in 4000mah.

I'm guessing your charger doesn't have a digital display?

Charge times vary between lipos. My 5000mah ones take 20 minutes to charge at 8amps.
 

cliofreak

Member
I'm using a hobby king eco6 charger. I've never setup how much goes in. I set it to 11.5 (3s) then set it to 2.5 rate then it checks the battery and then starts. Maybe I'm not putting in as much as they can take?
 





Carapau

Tek care, lambs ont road, MRF Moderator
I think you would benefit hugely from reading this. Your lipos are the heart of your machine so worth spending some time learning about them. Ben has given you an excellent starting point and hopefully the link will start to bring you up to speed.
 


cliofreak

Member
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Thanks guys for your help. Im still trying to figure this out. I can't seem to change how much goes into the lipos, it just automatic. These 3 pics might help. One is right after the quad beeped and I was loosing powers (forward to keep it level i had to push all the way forward then even that didn't work...this was inches off the ground). If you count up the V is more like 11.4 left in the battery but the quad beeps at 10.5 and i felt the power dropping. The other two pics show the lipo at almost full charge. It balancing and one cell is catching up. This charger is a mystery to be honest. Its shutting off and beeping now when it says 12.09V and it charged from beeping quad to beeping charger in 7 1/2 mins!! Weird!
 

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cliofreak

Member
Isn't 4.37V way too high? I though they're all suppose to be 4.2V!

Im going to try to balance them all to 4.2 and then run the timer again to see if I get more that 3min 30secs flight time. The quad lost power when the cells read -
3.2 4.11 4.11

That does not look right to me!
 
Last edited by a moderator:

Carapau

Tek care, lambs ont road, MRF Moderator
It looks like you have a goosed cell hence the probs. if you can't get all 3 to 4.2v on the charger then best to bin the battery and get a new one I reckon


Sent from my iPhone using Tapatalk
 

cliofreak

Member
It looks like you have a goosed cell hence the probs. if you can't get all 3 to 4.2v on the charger then best to bin the battery and get a new one I reckon


Sent from my iPhone using Tapatalk


For 40 mins now its been hanging around 3.76 4.20 4.21

Wont balance!
 

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