Welcome to PhantomPilots.com

Sign up for a weekly email of the latest drone news & information

Flight times went from fantastic to terrible

Discussion in 'Other DJI Multi-Rotors' started by SammyB, Apr 13, 2014.

  1. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    So I recently installed pretty much every module you can put on the F550, IOSD Mini, Can-Hub, Datalink and have been having absolute crap flight times . I literally get less that two minutes before the low voltage meter beeps at me but upon checking it shouldn't have hit that limit. I fly a 6400mah 3S nano-tech (506grams) battery at 100% and in two minutes it drops to something like 63%. Previously I was getting around 12 minutes flight time without these modules.

    Also I have the stock setup in terms of motors and am using 10inch props.

    I'm not to silly not to realise that obviously the modules would draw some power and the added weight would effect flight times but this is ridiculous. I'm assuming I have a faulty module? Also just plugged in the battery before and it was flashing red repeatedly from the naza, disconnected battery and tried again, no problem and startup sequence initialised but as soon as I was in the air I got the low voltage warning once again.

    You guys are awesome and would love your input. I literally have no idea what's going on...

    Voltage levels as shown below. They were working normally before the modules were added on and upon landing I'd have 25% left in my battery.
    [​IMG]

    UPDATE:
    F550 with GoPro, battery and all modules attached is 2.1kg's
    F550 with GoPro, without batteries and all modules attached is 1.6kg's.
     
  2. EMCSQUAR

    Joined:
    Sep 5, 2013
    Messages:
    1,692
    Likes Received:
    6
    Location:
    N 44.895 W 93.354 Minnesota
    First take a fully charged battery (12.6/12.5) calibrate your voltage. Then set your 1st battery level at 10.8 and 2nd level 10.6 (loaded), loss set at 0.50 then see what flight times you get.
     
  3. OI Photography

    Joined:
    Sep 23, 2013
    Messages:
    5,542
    Likes Received:
    17
    Location:
    Clarksville, TN
    +1

    Sammy, just leave your no-load values what they are, and change the loss value to whatever is necessary for the final level values to be at what EMC stated above. The final levels are all set a bit high now, not sure if that's what they were at when you got better flight times (maybe the loss values got cleared by mistake)?

    You'll also want to get a handle on your total flight weight...I would be seriously surprised if it's the main factor in your flight time drop, but it's always a good idea to have that measurement when testing different configs to milk every minute of flight you can.

    Also (sorry if I've asked you this before), do you absolutely need the canhub?
     
  4. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    Thanks for your those levels EMC! I'v adjusted it and I assume it's correct? Shown below. OI Photography what should my loss be at if I leave the no load levels as they were? I haven't changed the low voltage settings before as it worked fine off that bat and were super accurate, having around 20% left upon landing.

    I'll check my weight now and see what it comes up as, but obviously those modules don't weigh much and like you said it would be preety surprising if they were the contributing factor.

    I'd love to get rid of the can-hub but to use the Downlink I need it sadly :/

    [​IMG]

    UPDATE:
    F550 with GoPro, battery and all modules attached is 2.1kg's
    F550 with GoPro, without batteries and all modules attached is 1.6kg's.
     
  5. OI Photography

    Joined:
    Sep 23, 2013
    Messages:
    5,542
    Likes Received:
    17
    Location:
    Clarksville, TN
    The DataLink should plug in directly to the spare canbus port on the side of the iOSD...no need to use the hub as a go-between, unless you have another DJI module in the mix I missed. If you have the BTU connected on the 550, you can just connect it to the ground end of the data link instead.

    Set your levels like this:

    1st level no-load: 11.8
    loss: 1.00
    1st level loaded: 10.8

    2nd level no-load: 11.6
    loss: 1.00
    2nd level loaded: 10.6

    You can technically tweak the no-load levels and the load numbers themselves all you want, as long as the "loaded" values end up as specified above. The loaded numbers are the ones that trigger the LED and then the auto-land...the other numbers are just there to help you do the math basically.
     
  6. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    Thanks OI, changed my levels over to yours and am about to take it out and see what times I get. I actually pulled all of my modules out but you do actually need to Canbus to use all of the modules as far as I can tell. I'v already got my downlink setup with the bluetooth module.

    I'll let you know how it goes.
     
  7. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    UPDATE:

    Just took it for a low fly around my house (not hovering) and with the 6400 I got 10 minutes with 17% remaining (low voltage needs to go up a lot as I was literally metres from me when landing but obviously I wont be when I'm flying it elsewhere).

    Also tried it on my Storm 5000mah and got 7 minutes with 22% remaining (guessed this one as the low voltage warning obviously wont work).

    Any suggestions? The guy I fly it with locally here told me I should just disconnect all the modules and fly it as I originally did then start reconnecting modules, which I will be doing tomorrow. We both think it's the bluetooth module but could all of these modules be effecting my flight times this much? Seems kinda ridiculous.

    The times above are not really an improvement either. I have flown in high winds and over 1k away in the past for around 11 minutes and still had time to spare.
     
  8. FangsCPO

    Joined:
    Apr 7, 2013
    Messages:
    793
    Likes Received:
    3
    Location:
    Chula Vista, CA
    Here are my setings

    No Load: 11.30v.
    Loss: .50
    Loaded: 10.80v

    No Load: 11.00v
    Loss: .50
    Loaded: 10.50v

    IMHO your numbers were to high and you had no LOSS.

    I'm using a Onyx 3S 6400 35C and my max flight time right before the first red light blinks is at 11:30 minutes.

    I usually land at nine minutes and when I put the battery back on the charger I have about 25 percent battery left.

    Sent from my SCH-I535 using Tapatalk
     
  9. OI Photography

    Joined:
    Sep 23, 2013
    Messages:
    5,542
    Likes Received:
    17
    Location:
    Clarksville, TN
    Very interesting.

    Sammy, you can put in the same numbers Fangs listed above, but those will actually push your batts even a pinch further than the ones you tested last night did. Tell me this, have you weighed the modules you removed? I seriously doubt they're the cause of your significant reduction in flight time...other than the weight they add they shouldn't have any impact on your effective times.

    As far as the components that need canbus on the aircraft...you should be able to plug the iOSD mini into the port on your PMU, and then plug the Data Link in to the spare port on your iOSD mini. If you do that, there shouldn't be any need to lug around the canbus hub as well. Connecting the BTU to the ground end of the Data Link instead of the air end should allow you to use the assistant app just the same as if it was mounted on the aircraft.
     
  10. FangsCPO

    Joined:
    Apr 7, 2013
    Messages:
    793
    Likes Received:
    3
    Location:
    Chula Vista, CA
    Any chance your charger is not charging the lipo accurately? Any chance your lipo or one of the cells has gone bad? Can your charger check individual cell status>

    I know my voltage is displayed on my screen when I first start flying at 12.5v and within 2-3minutes it drops to 11.8v but then it stays there for a while. Just a few things to consider. Good Luck!
     
  11. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    Thanks for your help everyone. I'd love to not have to use the Canhub but to use the H3-2D, IOSD Mini and Datalink you do actually need it to connected everything as far as I know. Also the Bluetooth module is connected to the groundlink, the module on the my F550 is the Datalink.

    I'v actually been charging across 3 charges and using two 6400Mah's so I doubt it's charging problem (I wish). I haven't weighed the modules and have simply disconnected them for my tests but honestly they really don't weight much. Together then Can-Hub, IOSD Mini and Datalink probably weigh something like 120g's.

    I actually think I may of found one of the issues which seemed to be my transmitter. I did a flight without any modules connected other than my H3-2D gimbal and without a fpv transmitter and got 12 minutes on my 6400Mah and had 16% remaining (with more room for landing as my Voltage still isn't exactly where it needs to be I'd actually have 11:15 minutes).

    For my second test I reconnected all the modules and transmitter and flew for 9 minutes and had 28% remaining. Obviously the modules are making a preety major difference. Is this normal? Or do I most probably have a faulty module?

    Again, thanks for your help everyone! It's really great to have your expertise.
     
  12. OI Photography

    Joined:
    Sep 23, 2013
    Messages:
    5,542
    Likes Received:
    17
    Location:
    Clarksville, TN
    It's a community experience ;)

    120g added to a Phantom can rob you of two full minutes of flight, so while they won't take quite that big a bite out of your 550's flight time, you may lose well over a minute when you add that weight.

    I can assure you that the canhub isn't necessary for the gear you have. Just connect the iOSD mini to the canbus port on the PMU, then connect the Data Link to the spare canbus hub on the side of the iOSD mini. That's it...no other connections needed for those. That will at least allow you to shave off the weight of the hub and its cable.

    I doubt you have a faulty module anywhere or abnormal power drain...with the weights differences and flight times you've had in testing it sounds like everything adds up just about right now. Once you have the voltages dialed in just right the test results will be a little more reliable and it'll be easier to put the finger on whether or not there's anything to be worried about.
     
  13. Pacman

    Joined:
    Oct 9, 2013
    Messages:
    26
    Likes Received:
    0
    With the gimbal, iOSD min, and datalink you do need a can-bus.
     
  14. OI Photography

    Joined:
    Sep 23, 2013
    Messages:
    5,542
    Likes Received:
    17
    Location:
    Clarksville, TN
    The iOSD min and data link do need to plug in to a can-bus port....but you don't need the canbus HUB for that...there's enough ports already.
     
  15. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    I'm pulling everything apart today so I'll confirm that but I'v taken the top off twice and connected all the modules but I don't think there are enough ports without the can-bus. I'm probably wrong, we'll see haha.

    I'm testing a heap of configurations today so I'll do up a table with all the data and post it here. Hopefully it helps you guys out in the future as well.
     
  16. OI Photography

    Joined:
    Sep 23, 2013
    Messages:
    5,542
    Likes Received:
    17
    Location:
    Clarksville, TN
    Derp, scratch that, you all are right. I totally overlooked the fact the GCU needs a canbus port too (even though you both tried to get that through my thick skull). My brain was still in Phantom mode :oops:

    Carry on!
     
  17. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    Haha, I thought I must of totally missed something because everyone kept saying I didn't need the Can-Bus :roll:
     
  18. OI Photography

    Joined:
    Sep 23, 2013
    Messages:
    5,542
    Likes Received:
    17
    Location:
    Clarksville, TN
    Nope, you were right all along. This confusion will happen to you a lot when you hang around with us old farts.

    On the Phantom the GCU is built in to the mainboard and so even those using the Zenmuse on one don't need that extra port available...and I'm guessing (hoping) I'm not the only one who forgot that doesn't apply on other platforms when they gave you that advice :D
     
  19. SammyB

    Joined:
    Feb 27, 2014
    Messages:
    41
    Likes Received:
    1
    Location:
    Cairns, Queensland, Australia
    Haha, I'm preety sure everyone forgot while giving me that advice ;)

    Also, I made up a table with my flight times over the last few days. Hopefully it help a few people out, and I'll probably make a public one that everyone can contribute to later tonight.

    https://docs.google.com/spreadsheets/d/1A1KFQaa7Q18Ro5wcQidmfExCZd2vn80RnQJHG3hvRvw/edit?usp=sharing
     
  20. ElGuano

    Joined:
    Sep 4, 2013
    Messages:
    2,219
    Likes Received:
    4
    Technically, you don't even need a canhub to add additional accessories, just some spare wires and solder. Open that thing up and tell us what you see ;)