Issue with F550 and battery life

[rilot]

Hi guys
First post here but long time lurker.

I've recently built an F550 to fly having caught the multirotor bug from a DJI Phantom but I'm having an issue with it. Maybe due to lack of knowledge.

Spec of the copter:

F550
10" props
Landing gear
GoodLuckBuy gimbal
Naza Lite with GPS
GoPro Hero 3 black
200mv 5.8GHz TX
Suppo OSD
DX8 with telemetry module
Vid Tx, Gimbal and OSD are powered from their own 800mah 2S lipo.
I'm using 2 x 2200mah 3S lipos in parallel

The issue I have is that the copter will fly for no more than about 2 mins before I'm getting a low batt warning. I've disabled the Naza batt warnings and am instead using the telemetry on the DX8 to get a reading. I've set my low warning to be 11.4v. I'm getting a load voltage drop of about 0.8V which is pretty high.

My questions are:
Is this normal for a 2 x 3s 2200mah setup?
Should I be instead using 4S batts with the load I'm carrying?
Or do I have another problem?

 

[PeteDee]

What C rating are your packs?

What motors are you using?

What is your flying weight?

What current do you draw while hovering?

What GoodLuckIfYouGetWhatYouPaidFor gimbal are you using?

Does your Suppo OSD setup include current sensor, this is the one most important bit of info you need on an MR?

3S should be fine but 4400mh is only going to give you a low run time.

How much do you put back in to your packs after the 2 minutes flying and when the packs are at 11.4 volts?

Pete

 

[thehelidude]

Adding a gimbal drastically reduced my flight time. (Gopro2 Rctimer gimbal) I went 4s 6000mah and now I have enough power and ok flight time.

 

[thehelidude]

That's with 10 inch props. Also, I upgraded to graupner props because if you look at how easily plastic props bend I think they're losing efficiency by bending

 

[rilot]

What C rating are your packs?
30C

What motors are you using?
Stock DJI

What is your flying weight?
Will weigh it in a bit

What current do you draw while hovering?
No idea

What GoodLuckIfYouGetWhatYouPaidFor gimbal are you using?
The cheap one that loads of people have been buying with a Martinez controller board. THis is powered from a separate lipo.

Does your Suppo OSD setup include current sensor, this is the one most important bit of info you need on an MR?
No, at least I don't think so.

3S should be fine but 4400mh is only going to give you a low run time.
2 mins low?

How much do you put back in to your packs after the 2 minutes flying and when the packs are at 11.4 volts?
This is the odd thing. They are taking only about 1100mah back.

 

[rilot]

It weighs in at 2.32kg fully loaded with everything.

 

[europe]

Just to be sure - have you checked your voltage reading with a multimeter so that the Naza sees the same voltage? (Voltage calibration)

 

[rilot]

Just to be sure - have you checked your voltage reading with a multimeter so that the Naza sees the same voltage? (Voltage calibration)

I will do that but I'm not using the Naza low voltage stuff. Just monitoring by the telemetry from the DX8.
I did use the Naza voltage monitor a couple of times and it goes to first level warning after about 2 minutes. Same as my eyeballing the telemetry.

 

[OneStopRC]

Some of your problem is most likely with the parallel connection, my guess is you bought it from eBay or somewhere like that? if so, the wires connecting the two batteries are inferior in size to the battery wire gauge. I have seen people make these using 16AWG when they should be using 10AWG or 12AWG at the least...

6 motors, 10" props, Gimbal and landing gear... plus the rest of your goodies is probably too much for the 2200 packs. Either shed some weight, or shed some $$ in some lower KV motors on 4s lipo with bigger props. I bet your DJI motors are getting nice and hot... hope they don't fail on you.

 

[rilot]

I made the parallel connector myself using 10awg cable.

What motors would you recommend for this weight? I figured I would need to swap them out at some point anyway so might as well be now.