Running duel battery setup

4Li · Jun 24, 2014

Hi Guys,
I need advice on running duel batteries on my Fc40. My setup is : Tarot T2 Gimbal with Gopro H3, 9" P2 props. With standard 2200mah battery I get 7 min flight time on total take off weight of 1.3kg. Now I want to add a Boscam fpv on and planning to fit two batteries in order to increase flight time. What would be the best mah to run duel to get max flight time with added weight. I was thinking 2x 1800mah. Also can I power the fpv of one of the balance cords or should I add an extra 800mah for the fpv.

npalen · Jun 24, 2014

My FC40 is set up with GoPro on gimbal and running a 4000mah mounted crosswise under the fuselage behind the gimbal. I get 13-15 minutes with this setup but get about the same time with a pair of 2200mah. One 2200 is in the original battery holder and the second is behind the gimbal as mentioned above. The advantage of the dual setup is using existing 2200mah batteries which are about half the price of the 4000mah. Disadvantage is charging and handling two batteries verses one and a dual cable wye is required.
The 4000mah I'm using weighs about 305 grams and the pair of 2200's weight about 345 grams. Weight with battery is in the area of 1200 grams with the 2000mah.

4Li · Jun 25, 2014

Thx npalen for the reply. I have two 2200 mah batteries with y cable I will run it like that and get a 4000mah to see the differance. I guess I have to play arround till I get the best result.

npalen · Jun 25, 2014

viewtopic.php?f=20&t=14933
This is one way to mount the extra battery. I used a thicker piece of plastic and counterbored for the screw heads instead of bending. Also used a tiny aluminum plate inside the fuselage drilled and tapped for the two mounting screws.
The Phantom seems to balance quite well with this mounting.

4Li · Jun 25, 2014

So this afternoon I took my Fc40 for a test flight with 2x 2200mah batteries. From take of it seemed fine, hover perfectly and handled quit well despite the extra weight. I did casual flight and 3 min into flight started to struggle with hover. At 5 min 10 sec it descended slowly even though I was already at full throttle. It touched down at 5 min 17 sec. Battery voltage was sitting at 11.6v and my first warning is at 11.1v. So it was no failsafe just 11.6v is not enough juice to keep the bird up.
Here is my take of weights
Phantom+Gimbal+ Gopro =1073kg
Phantom+Gimbal+Gopro+2200mah bat=1240kg=7 min flight
Phantom+Gimbal+Gopro+2x 2200mah bat=1410kg=5 min flight
The 1500mah batteries is 117g that is 234g for 2 at 30th mah total so that will be my next try.
Will post the results.