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Arbolest

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About Arbolest

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  • Location
    Newark, California
  • EUC
    MSuper V3S+, Monster, Ninebot One E+

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  1. Hey, @Marty Backe, is there any more concrete info (coughschedulecough) concerning the various group rides you have planned for the week of the event? I have a tag-along that will be coming to the games with me that is interested in the group rides, and I was hoping to entice them into coming down a day or two earlier than we originally planned so that we can take part in more of the fun...
  2. This looks like it was great fun! Makes me want to move down there just so I can take part too!
  3. I feel for ya. I was practicing for the LA EUC games the other night on my Monster and was practicing idling when I suddenly decided I wanted to ride backwards for a while. Ended up getting stuck in a continuous left-hand loop because of all the cars in my cul-de-sac and ended up so dizzy when I tried to stop that the Monster almost went down... This is kind of an evil challenge...
  4. Those six screws are for a second row of MOSFETs that are running down the center of the board underneath it. It actually uses two rows of them for the motor control circuitry, one on the right side of this picture, and one that goes down the center of the board. Both rows are screwed to the heat sink behind it, and that heat sink is exposed to open air near the spinning wheel for cooling.
  5. This... was so much fun to watch and got me so excited... I need to go out and ride. Right now. See y'all later!
  6. You seem to be seriously misunderstanding what I was trying to say Eddie. I am fully aware that power does not equal torque, and nowhere in my post did I say that it does. What I was trying to get across is that the electrical circuit made up by the battery packs, the motor, and the control board will have a certain amount of current flowing through it based primarily on the voltage that the control board exposes the motor to and the resistance of the motor windings. In the highest-demand scenario, where the control board is exposing the motor to the full battery voltage (basically shorting the battery across the motor), the amount of current that the circuit will have running through it can be calculated by the simple equation V=IR. Or, written another way, I = V/R. Maybe this example will work better for you: Let's assume that we have two simple circuits, each having a battery pack and a motor. Assume the motors are the same (same internal resistance) and that the battery packs are an 84v and a 100v pack. When you close the circuits, which one is going to have more current flowing? It's simple to calculate it: I = V/R Current flowing in the circuit = Voltage of the battery pack / Resistance of the motor Let's go with a resistance value of 1 ohm for simplicity's sake (and because I don't know the actual values for our wheels' motors ). For the 84v circuit: Current = 84/1 = 84 Amps For the 100v circuit: Current = 100/1 = 100 Amps So like I said in my long post before, as long as the battery packs can both source the required current, the 100v pack will ALWAYS be able to generate more theoretical torque in that motor! Addendum: I would just like to highlight again one of the last points I made in my large post above. I can have all of the current capacity in the universe, but if my electrical circuit doesn't generate a demand for it, then it's wasted and will never get used.
  7. This. No matter what opinions all of us may have here, at least we can all agree these things are fun as heck and should just be enjoyed. Right on Marty.
  8. That would be fascinating to have delivered to you. I'm imagining a crate strapped to a pallet being offloaded from a Fedex truck and what the neighbors would think
  9. Yup... I think all of these big modern wheels need some form of removable interlock on the start button. Doesn't need to be a "key" as such, but something physical that will prevent them from being able to turn on without it.
  10. Jeebus. This is why I installed the equivalent of a key switch on my wheels, so they can NEVER accidentally turn on.
  11. Also, I guess it was a really sideways way of saying it, but all I was trying to say with that rant is that when people here talk about Amps = torque, they seem to be confusing the number of Amps that the wheels are actually using and the number of sustained Amps the battery packs are capable of providing for long periods ON PAPER, and they are NOT the same number.
  12. Momentarily? Think welding level amps and you're in the ballpark.
  13. Ok guys, this has been bugging me for a looooong time in these conversations. Unless the 100 volt wheel is running with an absurdly low number of packs in parallel, the100 volt wheel will always win. While everyone here has been yelling about how Amps = torque and Volts = speed and so the wheel with the most packs in parallel will obviously have more torque and grunt, they seem to somehow be missing the fact that that's not the whole story behind what is going on in one of these systems... Remember, the most important thing to consider here, above ALL ELSE, is V=IR. (voltage = current x resistance) In our situation, all things being equal, an 84v battery pack's maximum power output will never be as high as a 100v battery pack's. The total amount of current that is going to flow through the motor only really depends on the voltage the motor is exposed to and its internal resistance. Now, assuming the motors on the 84v and 100v wheels are actually the same, then as long as the battery packs can both source the required current, the 100v pack will ALWAYS be able to generate more theoretical torque in that motor! And the 100v pack can DEFINITELY source the current. The theoretical instantaneous current (amps) output of these battery packs is WAY higher than what is commonly quoted here. The ~10 amps per cell number that gets thrown around is at the high end of their nominal constant discharge rating, not what they are actually capable of delivering when they are essentially shorted (across, say, the motor). All the control boards in our wheels do to regulate the motor's power output and speed (simplified explanation of course) is regulate the voltage that the motors are exposed to. If a control board needs to provide a momentary burst of acceleration, it is basically just going to expose the motor to the full voltage of the battery and let those electrons flow. Because the motor doesn't provide very much resistance at ALL (it's basically just a long piece of wire), this will allow a stupendous amount of current to flow. And guess what? The battery packs that we have in our modern wheels are ALL easily capable of providing this current, in either the 84v or 100v flavors. Everyone seems to be getting hung up on the debate between the 84v and 100v wheels at the "well the 84 volt wheels have more cells in parallel and will therefore provide more Amps" point. And while yes, the more batteries you have in parallel, the higher your theoretical current cap is going to be, you have to remember that in the highest-demand scenario we can put our wheels in, a single 84 volt (20s3p) battery pack can easily take care of it. They can provide way more current than our control boards will ever ask for, so it just seems silly to me that people are debating so vigorously over the supposed difference in torque between having 4 packs in parallel and 6 packs in parallel. Range anxiety aside, we don't even really need that many. I guess that in order to put this to rest we need an example... Imagine two identical wheels. Same motors, same over-engineered control boards, same wiring, same shell, same pedals, yada yada... Now, one wheel has a regular old 84v 1600wh battery pack. The other wheel has an 84v battery pack that is 1000 times larger (with 1000 times as many cells), measuring in at 1,600,000 wh . It can provide 1000 times as many amps as the smaller battery pack. Now, let's say that the giant battery pack is magical and has exactly the same mass and dimensions as its 1600wh little brother. Which of these wheels "has more torque"? Will either wheel actually perform any differently? If I were to use my regular old run-of-the-mill 1600wh wheel and race against my evil twin who is riding the 1,600,000wh wheel, is my evil twin going to take off like a bat out of hell and accelerate 1000 times faster than me? No. No he will not. I don't think there would be any difference at all between the performance of my regular old 1600wh wheel and the magical one. The reason is that I can have all of the current capacity in the universe, but if my electrical circuit doesn't generate a demand for it, then it's wasted and will never get used. I reiterate from above: In our situation, all things being equal, an 84v battery pack's maximum power output will never be as high as a 100v battery pack's. V=IR
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