New Here, Need some advice on my ZONDA

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  • Speedfreek
    Senior Member
    • Apr 2018
    • 276

    #16
    Originally posted by CraigP
    I think you are asking for ESC trouble trying to run saw rotation speeds with ESC’s rated for 6s while running on 6s. You need to de-rate that voltage spec, because you will have higher ripple voltage. I think you need 8s rated ESC’s as a minimum. Designing the electrical system for saw at +40,000rpm is no trivial matter. The motor kv sounds too high and ESC’s not rated high enough. Just my 2 cents...
    Thanks for your input, if i was to stay with the 180A ESC What TP motor 40?? Would you recommend and what KV FOR 6S ?
    I have got good cap packs which keep ripple voltage bellow 1.9 v
    MYSTIC 138 119 MPH so far

    Comment

    • CraigP
      Fast Electric Addict!
      • May 2017
      • 1464

      #17
      Well the Cap Bank is just a default requirement when you run at rated ESC voltage. Unless your using an oscilloscope, you’re not going to see the real ripple. Just keep in mind, a mosfet only needs to be at over volt for one millionth of a second for it to breakdown. At these high current levels we run, there is zero tolerance to overvolt, and I think the ESC specs are overstated, as are most electronic devices. You’ll just have to discover these boundaries for yourself. You haven’t presented enough info to help on specifics. Need to know prop size, speed and runtime expectations. Are you racing or just want to go crazy fast?

      You might get away with the 6s ESC, but that’s an expensive boat, and I wouldn’t risk it.

      Comment

      • fweasel
        master of some
        • Jul 2016
        • 4282

        #18
        3200kV is way too many rev's on 6S. On a 4050 motor, you'd want closer to 1680kV on 6S voltage, nearly half the rpm's. I would suggest searching for build threads by srislash and rocstar, both have done some pretty fast twin builds on that size hull.
        Last edited by fweasel; 04-13-2018, 05:52 PM.
        Vac-U-Tug Jr (13mph)

        Comment

        • CraigP
          Fast Electric Addict!
          • May 2017
          • 1464

          #19
          The OP needs to consider the KT as well as the KV. That motor will have a small KT, meaning low torque. So you probably won’t get close to your calculated rpm based KV. That just pulls amps that cause the motor to get hot, for no return. A big reason to use higher volts is to be able to utilize motors with high KT.

          Comment

          • Speedfreek
            Senior Member
            • Apr 2018
            • 276

            #20
            Originally posted by CraigP
            Well the Cap Bank is just a default requirement when you run at rated ESC voltage. Unless your using an oscilloscope, you’re not going to see the real ripple. Just keep in mind, a mosfet only needs to be at over volt for one millionth of a second for it to breakdown. At these high current levels we run, there is zero tolerance to overvolt, and I think the ESC specs are overstated, as are most electronic devices. You’ll just have to discover these boundaries for yourself. You haven’t presented enough info to help on specifics. Need to know prop size, speed and runtime expectations. Are you racing or just want to go crazy fast?

            You might get away with the 6s ESC, but that’s an expensive boat, and I wouldn’t risk it.
            No racing, just want to go crazy fast with about 10 min run time 80 mph with reliability, not asking for much lol .
            Prop size well let me now and i will purchase just trying to use what i have esc wise.
            MYSTIC 138 119 MPH so far

            Comment

            • Speedfreek
              Senior Member
              • Apr 2018
              • 276

              #21
              Originally posted by CraigP
              The OP needs to consider the KT as well as the KV. That motor will have a small KT, meaning low torque. So you probably won’t get close to your calculated rpm based KV. That just pulls amps that cause the motor to get hot, for no return. A big reason to use higher volts is to be able to utilize motors with high KT.

              Exelent, thats why i am here for real info so i can get the correct parts first time, these motors are for sale now.
              MYSTIC 138 119 MPH so far

              Comment

              • Speedfreek
                Senior Member
                • Apr 2018
                • 276

                #22
                Originally posted by fweasel
                3200kV is way too many rev's on 6S. On a 4050 motor, you'd want closer to 1680kV on 6S voltage, nearly half the rpm's. I would suggest searching for build threads by srislash and rocstar, both have done some pretty fast twin builds on that size hull.
                Thanks trying to, this electric boat thing is new to me, i am use to rc cars going crazy fast not boats as yet, thanks.
                Last edited by Speedfreek; 04-13-2018, 06:59 PM.
                MYSTIC 138 119 MPH so far

                Comment

                • srislash
                  Not there yet
                  • Mar 2011
                  • 7673

                  #23
                  An ESC is not going to like a 4pole motor at anything over 50k RPM. Really not like it. There is simply too much switching for it to keep track of. This is two pole motor territory. It takes some reading or bad experience to learn this stuff.
                  I have a Fantasm that is at 117mph and spinning 45k RPM. It takes work to get there, heck it takes work to do 100mph. Time and patience. Nothing you build and ‘drop in the water’ will do it. But then, that’s the challenge! Lol

                  Comment

                  • Speedfreek
                    Senior Member
                    • Apr 2018
                    • 276

                    #24
                    Originally posted by srislash
                    An ESC is not going to like a 4pole motor at anything over 50k RPM. Really not like it. There is simply too much switching for it to keep track of. This is two pole motor territory. It takes some reading or bad experience to learn this stuff.
                    I have a Fantasm that is at 117mph and spinning 45k RPM. It takes work to get there, heck it takes work to do 100mph. Time and patience. Nothing you build and ‘drop in the water’ will do it. But then, that’s the challenge! Lol
                    Just the person i was waiting and told to speak to awsome.
                    with the seaking 180A ESC is it capable of doing 80mph? And with what type of motor kv and props? Please
                    MYSTIC 138 119 MPH so far

                    Comment

                    • srislash
                      Not there yet
                      • Mar 2011
                      • 7673

                      #25
                      Originally posted by Speedfreek
                      Just the person i was waiting and told to speak to awsome.
                      with the seaking 180A ESC is it capable of doing 80mph? And with what type of motor kv and props? Please
                      Oh I don’t see why not, even 1700kv on 6s will get you there. The T-180’s don’t mind 6s at all as long as you don’t run the BEC portion of them. Keagan’s setup is a pretty good setup (TP 4050’s @2050kv). A pair of 2400kv’s would run quick on 4s and should get to 80 with the aforementioned time/tweaking, and would rip on 6s(or even 5s). I’m not sure of the amps mind you.
                      The Seaking ESC has a big ‘burst’ current so you may be ok. The original V1/V2’s were good but I’m not sure of the new ones. Which do you have? I should have asked that first I gues before saying they are ‘all good’.

                      Comment

                      • Speedfreek
                        Senior Member
                        • Apr 2018
                        • 276

                        #26
                        Originally posted by srislash
                        Oh I don’t see why not, even 1700kv on 6s will get you there. The T-180’s don’t mind 6s at all as long as you don’t run the BEC portion of them. Keagan’s setup is a pretty good setup (TP 4050’s @2050kv). A pair of 2400kv’s would run quick on 4s and should get to 80 with the aforementioned time/tweaking, and would rip on 6s(or even 5s). I’m not sure of the amps mind you.
                        The Seaking ESC has a big ‘burst’ current so you may be ok. The original V1/V2’s were good but I’m not sure of the new ones. Which do you have? I should have asked that first I gues before saying they are ‘all good’.
                        V3 , so which TP would be safest, best for 6S with the V3 you think Amp wise ?
                        MYSTIC 138 119 MPH so far

                        Comment

                        • CraigP
                          Fast Electric Addict!
                          • May 2017
                          • 1464

                          #27
                          Originally posted by Speedfreek
                          Just the person i was waiting and told to speak to awsome.
                          with the seaking 180A ESC is it capable of doing 80mph? And with what type of motor kv and props? Please
                          We can’t really give you good prop advice until you lock down the voltage/motor choice. If you want longer runtimes, then you need to go to higher voltage, that’s a no brainer. But if you make poor choices in KV and prop, then it just turns into a B-B-Que pit, if you know what I mean! I run 1400KV on 6s on a hydro, and 1450KV on 6s on a cat. You have a big boat, so you’re going to want to lean towards larger props to get good prop efficiency. I would not go over 1700KV... You can always sell those motors and put a crazy fast setup in at a later date, once you gain more experience. BTW, the days you will be able to open it up and run 80 are going to be few and far between, except for micro speed bursts. Any wind or wakes are going to put that boat on it’s head, but that’s just something that you seem determined to experience. From experience, it’s not much fun rescuing a flipped boat. I also recommend you put plenty of foam flotation in, cause you’re going to need it!

                          Oh, I have a third hydro running 8s on 1050KV, so you can see I’m a 30,000rpm guy, which is the quick sport boater’s sweet spot!
                          Last edited by CraigP; 04-14-2018, 12:39 PM. Reason: More info

                          Comment

                          • Speedfreek
                            Senior Member
                            • Apr 2018
                            • 276

                            #28
                            Originally posted by CraigP
                            We can’t really give you good prop advice until you lock down the voltage/motor choice. If you want longer runtimes, then you need to go to higher voltage, that’s a no brainer. But if you make poor choices in KV and prop, then it just turns into a B-B-Que pit, if you know what I mean! I run 1400KV on 6s on a hydro, and 1450KV on 6s on a cat. You have a big boat, so you’re going to want to lean towards larger props to get good prop efficiency. I would not go over 1700KV... You can always sell those motors and put a crazy fast setup in at a later date, once you gain more experience. BTW, the days you will be able to open it up and run 80 are going to be few and far between, except for micro speed bursts. Any wind or wakes are going to put that boat on it’s head, but that’s just something that you seem determined to experience. From experience, it’s not much fun rescuing a flipped boat. I also recommend you put plenty of foam flotation in, cause you’re going to need it!

                            Oh, I have a third hydro running 8s on 1050KV, so you can see I’m a 30,000rpm guy, which is the quick sport boater’s sweet spot!
                            I love your honesty , 6S for sure and maybe 1450kv TP 4050 can or 4060 ?
                            MYSTIC 138 119 MPH so far

                            Comment

                            • CraigP
                              Fast Electric Addict!
                              • May 2017
                              • 1464

                              #29
                              Originally posted by Speedfreek
                              I love your honesty , 6S for sure and maybe 1450kv TP 4050 can or 4060 ?
                              I think the Zonda is a dual. so 4050 will suffice. This will really help with maximizing your runtime too. You should be able to get close to 70 at about 150A/motor running an 1817-17 ABC prop. To go 80, you'll need to upgrade the ESC's to SW 220A or equivalent. The amp load will be about 190-200A/motor. It takes a lot of power to push a big boat like that at speed. Also, your setup is going to have to be impeccable. It will need to be trimmed to run on the last 1" of the sponsons, max! I would use water pickups in the rudder, because hull pickups might be running dry when fully trimmed out.

                              There's many other small things. Electrically, you'll need to isolate the ground loop created between the Recv and the ESC's. This unintended loop is responsible for just flaming the ESC's quite unpredictably. Search for "Cap Banks for Dual ESC's" to bone up on that. You've bitten off a big project, so realize this may be a longer road than you first expected.

                              Comment

                              • srislash
                                Not there yet
                                • Mar 2011
                                • 7673

                                #30
                                I would stick with 4050’s. That should be plenty for a Zonda. Definitely the lower Kv the better things are on runtime, amp spikes, heat, all of it. 60-70 should be easily attainable on 1400’ish Kv(or even a bit more).Then with proper prop choices more can be had.
                                Craig has sound advice. Remember, ‘ To win a race you have to finish the race’.

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