F550 Radio Setup

[Charlie.]

Thanks to you too gtranquilla:

1) I didn't calibrate the battery (don't have a voltmeter) but I did choose 3S and left the voltage protections alone (1st level = 10.8V, Loaded) (2nd level 10.4V loaded).
2)How can I tell if they are binding? They seem to compensate for the multirotor movement just fine though.
3)Temperate is 8C (according to yahoo weather)
4i)...
4ii)Batteries were brand new from HobbyKing. Balanced charging started at around 3.8V and finished at 4.2V per cell. About 2500mah were added during this charge.
5)I am using a PC power supply (unmodified). Output rating is 12V 8.5A Max 110W
6)Not really sure how to tell if they are faulty, some have more of a 'click' and spring into position when I turn them with my hand than others.
7i)Stock F550 (props,ESC,motors etc) with 5000mah 3S, landing legs and gimbal (without GoPro in at the moment), GPS, Naza, receiver. AUW is roughly 2kg
7ii)Pretty much took it outside plugged it in and flew it so... No
8)1st level = 10.8V, Loaded --- 11.5V, No Load
2nd level = 10.4V, Loaded --- 11.1V No load


I think it might be to do with the batteries for some reason. When I balance charged them they did finish at 4.2V per cell when the Accucel-6 said 'FULL'

Please don't be a faulty Naza... PLEASE don't be a faulty Naza...

 

[Charlie.]

I have started a balance charge on my 5000mah LiPo and the overall voltage was at 11.77V and the three cells were all showing roughly 3.92V (from the charger (turnigy Accucel-6)). Does this mean that the LiPos are fine but something else is causing the flashing red light?

Any more help would be much appreciated

 

[gtranquilla]

Get rid of the gimbal outputs and extra payload until the battery issues are first resolved..... And for the 8 and 9 inch props you need to use 4S batteries..... as per the following excerpt from the F550 specs/manual.
If you are using 10 inch props you can use the 3S batteries but your payload weight can quickly become a problem. If too light, your MR will bounce around in light breezes. If too heavy your batteries will drop voltage levels fast under the working load and cause 1st and/or 2nd level battery protection to kick in. And don't forget to tell the NAZA controller which size of batteries it will be using.....
View attachment 9608

Thanks to you too gtranquilla:

1) I didn't calibrate the battery (don't have a voltmeter) but I did choose 3S and left the voltage protections alone (1st level = 10.8V, Loaded) (2nd level 10.4V loaded).
2)How can I tell if they are binding? They seem to compensate for the multirotor movement just fine though.
3)Temperate is 8C (according to yahoo weather)
4i)...
4ii)Batteries were brand new from HobbyKing. Balanced charging started at around 3.8V and finished at 4.2V per cell. About 2500mah were added during this charge.
5)I am using a PC power supply (unmodified). Output rating is 12V 8.5A Max 110W
6)Not really sure how to tell if they are faulty, some have more of a 'click' and spring into position when I turn them with my hand than others.
7i)Stock F550 (props,ESC,motors etc) with 5000mah 3S, landing legs and gimbal (without GoPro in at the moment), GPS, Naza, receiver. AUW is roughly 2kg
7ii)Pretty much took it outside plugged it in and flew it so... No
8)1st level = 10.8V, Loaded --- 11.5V, No Load
2nd level = 10.4V, Loaded --- 11.1V No load


I think it might be to do with the batteries for some reason. When I balance charged them they did finish at 4.2V per cell when the Accucel-6 said 'FULL'

Please don't be a faulty Naza... PLEASE don't be a faulty Naza...

 

[Charlie.]

Thanks gtranquilla,

I am using the 'NEW' DJI 1038 props (with my 3S battery). So you think the problem is to do with the battery and weight of my multirotor, not a faulty NAZA/calibration or incorrect wiring?

I have just fully charged one of my LiPo batteries, should I plug it into my copter and calibrate the naza software voltage to 12.6V?

Also on a semi-related note, where is the best place to mount the battery, at first I mounted on top, but then I mounted it on the plate on my landing gear (directly underneath the F550 bottom plate.

What would you advise me to do in my situation?

 

[b0nafide]

My battery is a 3S 5000mah 25C Zippy Compact battery.

Could this not be the problem?

The 25C? Shouldnt it be 30 or 35C?

 

[Charlie.]

Yeah I am beginning to think it could be!

Can anyone else confirm that this rating is too low because if so I think I will need to buy some new batteries

 

[OneStopRC]

As I was saying, The more amps you pull, the lower your volts will go. If you do not have the means to supply the current, in your case with the 25C, your voltage will drop out under load. Increase your "C" rating and you will see this go away.

For now, as mentioned above, lighten that beast up. Remove the Gimbal, Remove the landing gear and just get used to flying it around for a while.

The more weight, the more your motors will work, the more load on that 25C battery. It can't deliver what your asking of it.

 

[Charlie.]

Oh that's annoying!

Guess I will have to sell these batteries and buy some new ones What C rating do you think would be good? 35C, 40C?

Does anyone know where I can get some 4000-5000mah 3S LiPo batteries with the XT60 connector? Or at least some with 12AWG wire so that they are easy to solder onto the XT60 myself?

 

[gtranquilla]

When using 3S batteries with my F550 I always use two in parallel, i.e., each is 25C and 5000 mah = 10 amps total current on demand.
While the intent is to increase flight time...... if I understand the theory correctly you will then not need 35C or higher when placing two batteries in parallel.

I prefer to locate my batteries on the top of the MR since the bottom area is needed for the landing gear, gimbal, camera etc.
But the "z" parameter in the MR calibration has to be adjusted according to where the vertical center of gravity is so that your IMU will not be struggling to keep the MR directly under the batteries at all time. T
ie a string to the bottom center plate of your MR and lift the MR with the string from one side.
If the top of your MR hangs lower than the bottom, your center of gravity is above you NAZA controller.
If the bottom of your MR tends to hang lower then the vertical center of gravity is below the NAZA controller.
Then adjust "z" as best you can accordingly (remember that the negative number may be required).

Oh that's annoying!

Guess I will have to sell these batteries and buy some new ones What C rating do you think would be good? 35C, 40C?

Does anyone know where I can get some 4000-5000mah 3S LiPo batteries with the XT60 connector? Or at least some with 12AWG wire so that they are easy to solder onto the XT60 myself?

 

[Charlie.]

So you're saying that I could keep my two 25C 5000mah batteries and use them in parallel, and although the C rating would stay the same, as each battery only has to work half as hard, together they can actually supply double the amperage?

This sounds like a good idea, but I am just not sure whether my hex would be able to take the extra weight, although my batteries are pretty lightweight, ~350g each. I am just worried about my props shearing off in flight, although I am using the NEW 1038 DJI props which are said to be much stronger.

If I were to use this setup my payload would be:

F550 (motors electronics etc) : 1.2kg
Landing Legs and gimbal : 300g
GoPro Hero 3 : 75g
2x 5000mah batteries : 700g
FPV transmitter and receiver 60g

Total of 2.335kg!

I just really don't want my props to break off in flight, or any screws coming loose because of the weight!

 

[Charlie.]

I removed the landing gear and took it for another fly around.

The red light did come on again but after a longer period of time I think.

So the batteries are probably the problem. If I try to run two of my 5000mah packs in parallel, does it matter what sized wire the harness uses? The ones on eBay all use 14AWG but my batteries have 10AWG? If 2 batteries with 10AWG wire join to this 14AWG harness what will the ill effects of this be?

My battery connector to the multirotor itself is only 12AWG, so I would have 2 pairs of 10AWG wire (from batteries) going to 14AWG wire (parallel harness) and then to the 12AWG (battery connector).

Surely this can't be good for it?!

 

[kloner]

You'd want 10 gauge

What battery charger do you have?

 

[Charlie.]

Turnigy Accucel 6

 

[kloner]

That one doesn't read internal resistance. Was curious if the pack is loosing IR making your problem. One over discharge is all it takes.

 

[b0nafide]

Are you sure on that weight for your batteries? Most 5A batteries are 420+g each.

 

[Charlie.]

Yeah they are the zippy compact 3S 5000 mah ones which are around 350g each which is why I bought them Should have bought one with a higher C rating it turns out though!

kloner, my batteries came from hobby king at roughly 3.8V per cell, I balance charged them to 4.2V per cell, used them both on my hexacoptef for a bit and have now recharged them and only 2200mah were added on the last charge so I am not sure I they are over discharged or not.

I think it might be what someone above said, that the battery cannot deliver the amps it needs (battery is 25C), so the voltage drops quickly. I am really not sure though!

 

[kloner]

25c 5000mah can deliver 125 amps cont, until there damage, then it's amp output cont drops like a rock.

Most stock 550 hover around 30 amps.

 

[Charlie.]

Is there anyway I can check if my batteries are damaged?

My Accucel 6 can tell me the cell voltages at the start of a charge and the finished cell voltages as well as how many mAh have been given to the battery.

Do you think running my 2 5000mah batteries in parallel would solve my problems? Or do you think new batteries are necessary?

 

[gtranquilla]

Run your system thru eCalc for multirotors and see if your stock motors can handle the weight with the 2 batteries in parallel and the full payload. And don't forget that the higher C rated batteries are almost always significantly heavier.

You will see in my signature below the details on the two MRs that I am flying. The modified F550 has all the items you have with the exception of FPV system but uses instead the DJI Datalink LK900 transceiver...... Also it uses larger motors and 10 inch x 5 Graupner props and flys with 2 x 25C 3S 5000 mah batteries.....and I can use two 4S 5000 mAH batteries as long as I don't go to full throttle within the 1st 4 to 5 minutes of flying!!!!

So you're saying that I could keep my two 25C 5000mah batteries and use them in parallel, and although the C rating would stay the same, as each battery only has to work half as hard, together they can actually supply double the amperage?

This sounds like a good idea, but I am just not sure whether my hex would be able to take the extra weight, although my batteries are pretty lightweight, ~350g each. I am just worried about my props shearing off in flight, although I am using the NEW 1038 DJI props which are said to be much stronger.

If I were to use this setup my payload would be:

F550 (motors electronics etc) : 1.2kg
Landing Legs and gimbal : 300g
GoPro Hero 3 : 75g
2x 5000mah batteries : 700g
FPV transmitter and receiver 60g

Total of 2.335kg!

I just really don't want my props to break off in flight, or any screws coming loose because of the weight!

 

[Charlie.]

Should I buy a couple of these and try it out?

http://www.hobbyking.com/hobbyking/...Flightmax_4000mAh_3S1P_40C_UK_Warehouse_.html

Apparently they only have 12AWG wires so should be easier to solder XT60 connectors on to than the 10AWG wires from my first batteries!

Do you think I could run 2 of the above batteries in parallel and it will be able to power my F550 with the payload in the quote above (AUW 2.335kg including 2 of these batteries). I am using the New DJI 10x38 props if that makes any difference.

Thanks guys.