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Lipo capacities. Are all lipos over rated in terms of capacities?

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    #61
    From : http://tviv.org/MythBusters/Barrel_o...t#The_Result_2


    Peeing on the Third Rail

    The Myth
    A guy is wandering through a railyard drunk and needs to relieve himself. He makes sure no trains are coming and he starts to pee onto the third rail, which is electrical, and a current runs through his urine and kills him.

    The Test
    First the Mythbusters must determine if it is actually possible for urine to conduct electricty. They learn that the voltage of the third rail is 650 volts and they determine that the resistance of urine is 10,000 Ohms. Using Ohm's Law they determine that it can resistance 65 miliamps and all that is need to make you stop breathing is 30 miliamps. Now that they know it is possible to be killed through urine, they go about making a body out of ballestics gel and figure out how to make the dummy urinate. After many failures of making the dummy and success with urinating machine, they finally are able to test. They set up the dummy so that it will urinate onto a mock third rail that they set up. The first test shows no results. They decide to make the ground below the dummy wet and try again, however nothing happens. They try removing the shoes and making the ground wet again, however failure. They determine that the stream is not constant because by the time it has hit the rail it has broken up into drops. They increase the size of the tube that allows urine to exit and move the rail up so it is a few centimetres away. They try this time to success.

    The Result
    Busted. Although it is possible for someone to kill themselves by peeing on the third rail, it is very unlikely. (Note, this myth is revisited in Myths Revisited)

    Comment


      #62
      Originally posted by Adrianli View Post
      From : http://tviv.org/MythBusters/Barrel_o...t#The_Result_2


      Peeing on the Third Rail

      The Myth
      A guy is wandering through a railyard drunk and needs to relieve himself. He makes sure no trains are coming and he starts to pee onto the third rail, which is electrical, and a current runs through his urine and kills him.

      The Test
      First the Mythbusters must determine if it is actually possible for urine to conduct electricty. They learn that the voltage of the third rail is 650 volts and they determine that the resistance of urine is 10,000 Ohms. Using Ohm's Law they determine that it can resistance 65 miliamps and all that is need to make you stop breathing is 30 miliamps. Now that they know it is possible to be killed through urine, they go about making a body out of ballestics gel and figure out how to make the dummy urinate. After many failures of making the dummy and success with urinating machine, they finally are able to test. They set up the dummy so that it will urinate onto a mock third rail that they set up. The first test shows no results. They decide to make the ground below the dummy wet and try again, however nothing happens. They try removing the shoes and making the ground wet again, however failure. They determine that the stream is not constant because by the time it has hit the rail it has broken up into drops. They increase the size of the tube that allows urine to exit and move the rail up so it is a few centimetres away. They try this time to success.

      The Result
      Busted. Although it is possible for someone to kill themselves by peeing on the third rail, it is very unlikely. (Note, this myth is revisited in Myths Revisited)

      Yah I know. I saw it.
      Modded Esavage + 4S lipo + KB45 2300KV + HW150A
      Brushless Esky Lama with dual swash
      Esky Dauphin
      Walkera Lama 2
      Walkera 5G6
      Sparrowhawk XB + 2S lipo + 60A brushless esc + 6000kv motor.
      Brushless Mini LST + single servo mod
      Brushless Micro-T

      Comment


        #63
        high power and discharge rate batteries

        more safety Lifepo4 for rookie and practise,more powerful lipofor RC cars

        Apirl 22,2009

        sigpicno pay no gain ,actions speak louder than words

        Comment


          #64
          Danger, flames, water and lithium? interested yet?
          Posted 16 years ago, most of us had a little less common sense than we do now.I think it's obvious that you should not attempt this yourself.This is a very o...



          Video on lipo overcharge
          The LiPo is an extremely hazardous battery if mishandled. Watch what happens when I overcharge one at the end! Please pay attention to the warnings for this ...

          Comment


            #65
            Hi,

            firstly i must say that 'I-am-a-total-idiot' with electronics stuff. i am seeking some advise from you guys here.

            I have a few 2s lipo cells (china brand, rojak brand etc), all of them doesnt comes with balancer plugs. I am thinking of disconnecting them apart and make into 3s with balancer plug...

            A) is this appropriate?
            B) how to do it and if there is any connection diagram to follow?

            PS: sorry, my questions might be very stupid...
            Roll call from hanger
            -Kyosho, STRATUS 1600 Glider
            -JH Spitfire-25 size (no 2.)
            -Cap 232-15 size
            -GWS P51 Mustang EP, from a nice DH flyer
            -Dualsky Breeze PRO

            Kissed the ground...

            -Scanner
            -JH Spitfire-25 size (no 1.)

            Frequency

            -Spektrum, DX7

            Comment


              #66
              Originally posted by oldmanflying View Post
              Hi,

              firstly i must say that 'I-am-a-total-idiot' with electronics stuff. i am seeking some advise from you guys here.

              I have a few 2s lipo cells (china brand, rojak brand etc), all of them doesnt comes with balancer plugs. I am thinking of disconnecting them apart and make into 3s with balancer plug...

              A) is this appropriate?
              B) how to do it and if there is any connection diagram to follow?

              PS: sorry, my questions might be very stupid...
              i have actually disassembled and reassembled packs b4 but it is best that u dont attempt it since u have no electrical knowledge as it can be quite dangerous.
              For sale






              trex 700/ 12mm main shaft swash leveller. carbon type $22 only new

              Comment


                #67
                Originally posted by johndyl View Post
                i have actually disassembled and reassembled packs b4 but it is best that u dont attempt it since u have no electrical knowledge as it can be quite dangerous.
                totally agree,

                i have done 2cells connection b4, its the balancing plug that makes me confuse.
                Roll call from hanger
                -Kyosho, STRATUS 1600 Glider
                -JH Spitfire-25 size (no 2.)
                -Cap 232-15 size
                -GWS P51 Mustang EP, from a nice DH flyer
                -Dualsky Breeze PRO

                Kissed the ground...

                -Scanner
                -JH Spitfire-25 size (no 1.)

                Frequency

                -Spektrum, DX7

                Comment


                  #68
                  Originally posted by oldmanflying View Post
                  Hi,

                  firstly i must say that 'I-am-a-total-idiot' with electronics stuff. i am seeking some advise from you guys here.

                  I have a few 2s lipo cells (china brand, rojak brand etc), all of them doesnt comes with balancer plugs. I am thinking of disconnecting them apart and make into 3s with balancer plug...

                  A) is this appropriate?
                  B) how to do it and if there is any connection diagram to follow?

                  PS: sorry, my questions might be very stupid...
                  Like wat bro Johndly said, it can be dangerous if u dun know the basic well, n it is not worth the money n effort to 'Mix n Match' your lipos. Another issue is different batch/brand of lipos got their own individual capacity, the differences in the capacity of each cell will be more if it the lipos have been thru numerous cycle

                  Comment


                    #69
                    if u know how to find out the +ve and -ve of each cell using a multimeter then it will be easy..

                    after that just stack and connect/solder the cells in series. pardon my poor drawing..

                    For sale






                    trex 700/ 12mm main shaft swash leveller. carbon type $22 only new

                    Comment


                      #70
                      do make sure the cells match up(are close) in capacity, discharge ratings etc

                      also do practice maintaining above 3.7v for each cell due to the likelyhood of cell mismatch and always balance charge this packs
                      For sale






                      trex 700/ 12mm main shaft swash leveller. carbon type $22 only new

                      Comment


                        #71
                        yes, a bit scare abt the connection but i found this very simple diagram useful...



                        one main thing which i didnt thought of it is the diff character of individual cell. Mix & Match may end up like 'eating rojak from some particular store'...
                        Roll call from hanger
                        -Kyosho, STRATUS 1600 Glider
                        -JH Spitfire-25 size (no 2.)
                        -Cap 232-15 size
                        -GWS P51 Mustang EP, from a nice DH flyer
                        -Dualsky Breeze PRO

                        Kissed the ground...

                        -Scanner
                        -JH Spitfire-25 size (no 1.)

                        Frequency

                        -Spektrum, DX7

                        Comment


                          #72
                          Originally posted by johndyl View Post
                          do make sure the cells match up(are close) in capacity, discharge ratings etc

                          also do practice maintaining above 3.7v for each cell due to the likelyhood of cell mismatch and always balance charge this packs
                          John, kekeke for the life of me, I have been doing this to my lipo and this is my experience. Reducing lipo series to take away say a bloated cell works but all my tries to put together say 2s with 1 s to make 3s for example never quite work. No matter how I match them, find the best candidate like bought at same time etc, the batts somehow will charge fine, look fine but just doesn't deliver power I like to see anymore lol. The balancing will always go out of wack upon discharging suggesting poor matching, but that is the closest I can get to match lol. All brands from GWS to FP varying in different sizes to 4350mah all exhibited the same behaviour lol. I think the factory assembly process and selection is actually quite important.
                          Stop looking for a gyro in my plane, they are all in the head.

                          Comment


                            #73
                            Originally posted by edmond22 View Post
                            John, kekeke for the life of me, I have been doing this to my lipo and this is my experience. Reducing lipo series to take away say a bloated cell works but all my tries to put together say 2s with 1 s to make 3s for example never quite work. No matter how I match them, find the best candidate like bought at same time etc, the batts somehow will charge fine, look fine but just doesn't deliver power I like to see anymore lol. The balancing will always go out of wack upon discharging suggesting poor matching, but that is the closest I can get to match lol. All brands from GWS to FP varying in different sizes to 4350mah all exhibited the same behaviour lol. I think the factory assembly process and selection is actually quite important.
                            yep agreed bro.. these "rojak" packs should be used only on non-critical systems like maybe rc cars or setting up and not on something that can potentially crash and burn
                            For sale






                            trex 700/ 12mm main shaft swash leveller. carbon type $22 only new

                            Comment


                              #74
                              after reading, i think its better to buy new lipo...
                              do not try to rojak them.
                              not only the connecting and also you will need to have good soldering skills.

                              i try once that one of my balance wire fell off the battery and i solder it
                              back...... the feeling is like cutting a wire in a time bomb... i can not
                              imagine that the soldering rod touchs the other point...

                              i rather buy a new china brand lipo than making one myself.

                              I DO NOT WANNA LAST ONE OF MY FINGER OR HAND IN THIS HOBBY!!

                              Comment


                                #75
                                I think i dont wanna try anything stupid here...

                                just pain pain one time go and buy new cell instead...
                                Roll call from hanger
                                -Kyosho, STRATUS 1600 Glider
                                -JH Spitfire-25 size (no 2.)
                                -Cap 232-15 size
                                -GWS P51 Mustang EP, from a nice DH flyer
                                -Dualsky Breeze PRO

                                Kissed the ground...

                                -Scanner
                                -JH Spitfire-25 size (no 1.)

                                Frequency

                                -Spektrum, DX7

                                Comment

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