Welcome to PhantomPilots.com

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

No Battery - Running 200' DC Wire Directly to Phantom

Discussion in 'General Discussion' started by zdauexs, Dec 30, 2014.

  1. zdauexs

    Joined:
    Nov 1, 2014
    Messages:
    9
    Likes Received:
    1
    Has anyone tried running power straight to Phantom instead of using the battery? Watching videos online of "tethered uav's" seems fairly straight forward running DC power to Phantom. Seems weight of wiring (length) and enough amperage to run DC power at x(distance) would be concerns, along with entanglement etc.
     
  2. Buk

    Buk

    Joined:
    Feb 28, 2013
    Messages:
    654
    Likes Received:
    29
    Location:
    Iowa, United States
    You may have to look up the power requirements of your particular Phantom and calculate the voltage drop of a given length of wire and wire gauge required. Then calculate the weight of the cable (remember two wires required) and if the Phantom has enough lift to raise the additional weight off the ground. Remember too, stranded wire in your calculations, solid would not work as well for flexible tethering.

    http://www.bulkwire.com/wireresistance.asp

    Remember too, some Phantoms require smart battery connections for proper operation. So you might be working with the Phantom 1 for your power requirement calculations and not a Phantom 2 and it's iterations.

    Good luck, I'm a bit pessimistic about success considering entanglement in trees, cars, goal posts on football fields and of course your props.
     
  3. locoworks

    Joined:
    Jul 4, 2014
    Messages:
    471
    Likes Received:
    10
    there could certainly be quite a bit of wire for the weight of a battery, but what gauge wire would you need? if you said a stock 5000mah battery gave 20 mins, that is 15 amps in an hour so a cable that can deal with 15 amps ATLEAST would be required for a short tether where voltage drop isn't an issue and the quad would weigh less than with a battery on board. 1.5mm wire is around 15 amps but to be safe 2.5mm would probably be a better bet. but when you look at the wire sizes on board and the size of the big blades on the battery maybe 2.5mm would be too small???
     
  4. The Editor

    Joined:
    Aug 7, 2013
    Messages:
    568
    Likes Received:
    7
    100m of 14SWG silicon wire will weigh in at around 4kg so 200 feet/60m will be around 2.4kg. Multiply that by 2 and you have circa
    5kg of weight at an offset angle tethered to the Phantom.

    I doubt it would even get off the ground :lol:

    I haven't even gone into the voltage loss over that distance or the changing emf that will be generated around the wire with the current draw fluctuations.

    Forget it!
     
  5. locoworks

    Joined:
    Jul 4, 2014
    Messages:
    471
    Likes Received:
    10
    ignoring the BEMF for a moment what about using a helium balloon to do the lifting of the cable about 5 metres below the quad?? maybe 3 or 4 balloons, enough to lift the wire so the quad only has to be able to lift the weight of wire between it and the balloons. when you want to land you just reel in the wire below the balloons onto a spool as you lower the phantom using the sticks. when the balloons are ground level you land to the side.

    on the bemf front could something be put accross the wires near the quad to reduce the effects???
     
  6. macheung

    Joined:
    Dec 10, 2013
    Messages:
    246
    Likes Received:
    4
    Tethered wire with DC power, ballons oh my!
    I think we are getting way over our heads in this one... May be we can use some sort of laser power ground station that beams power to a receiver on the Phantom next. That might work if the receiver can be light enough.
     
  7. LandYachtMedia

    Joined:
    Dec 27, 2013
    Messages:
    353
    Likes Received:
    3
    Location:
    Central North Carolina, USA
    The phantom uses at its peak about 450 watts. To make a wire system that is light enough you would have to up the voltage. So at 11v that 450 watts need a bit over 40 amps. That takes a heavy wire. Boost it to 200v and the amps drop to about 2. 2 amps will flow easily on a 20 gauge wire. The issue then becomes building a power converter to drop the voltage and boost the current.

    This could certainly be done. Not exactly practical though.