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    Recommended 48V battery solution for dummy?

    hi there, I am looking for battery system solution for my up coming e-scooter conversion, rough target in mind is 100V/100A battery. What's the recommend battery system with pack/bms/charger solution that's easiest to get and maintain? I am thinking of stacking two high-discharging 48V...
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    Neumotor 44xx series anyone?

    a hint of update? $625 is more aligned with Astro3220 now 8)
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    Neumotor 44xx series anyone?

    thanks Gary! a group buy would be great :)
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    Neumotor 44xx series anyone?

    was wondering if anyone tried Neumotor's 44xx series? it's listed at $525 for 4410, sounds like a comparable compete against 3210/3220? http://www.neumotors.com/Site/Motor_Price_List.html
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    Important info on Castle controllers!

    the inductance of the motor is directly proportional to the number of turns. for instance, a 8-turn 3220 would have double the inductance of that of a 4-turn 3220. is Bob talking about a low-turn 3220/3210?
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    Astro 3210 group buy?

    i am in one of the few 1st group buy orders that haven't been shipped. mine is a 3220/7-turn/6-wire/double shaft. it's been 4 months since the group buy was formed so i started to worry, maybe i am too anxious :oops: actually i saw the other order that has the exact same configuration been...
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    Astro 3210 group buy?

    hi Matt, i am a bit confused, is it $50 or $20 for double shaft? :mrgreen:
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    Astro 3210 group buy?

    hi Matt, payment sent for a 3220 7-turn/6wire/double shaft/black-anodized (550+10+50)*1.04=644.8 thanks a lot! -georgeycc
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    Astro 3210 group buy?

    hi Matt, how much more for 3220 if i want the shaft to be 10mm and longer/stretching out from both ends instead of one end? my config will be 3220/7turn/6 wires/10mm shaft/shaft stretching out both ends/black can please let me know thanks, -george
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    Astro 3210 group buy?

    would buy a 3220 at $550 (can i ask for all 6 wires out?) is there updates on the sensor board? thanks
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    astro flight..paranoia or good business?

    looks like i am not qualified either :mrgreen:
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    *** Attention FET driving smart guys*** I need help. 300a RC

    i have a ebay "mystery pentium 100A" controller in hand so i also took a look of it's make. interestingly i found that how they rate the current capacity is very different to the Turnigy ones. for this Turnigy 40A, it has two mosfets per phase, per switch. each mosfet is rated "absolute max 20A...
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    *** Attention FET driving smart guys*** I need help. 300a RC

    Luke, what's the glue you're using to attach 4110's to the heatsink? how well is the insulation?
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    *** Attention FET driving smart guys*** I need help. 300a RC

    that Vcc is actually 12V bootstrapping supply that comes from this: ======= ST662A Series DC-DC Converter For Flash Memory Programming Output voltage: 12V +/- 5% Supply voltage range: 4.5V to 5.5V Guaranteed output current up to 30mA Very low quiescent current: 100mA Logic-controlled...
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    mounting hall sensors to R/C brushless motors

    hi Gary, did you find good spots for the sensors?
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    mounting hall sensors to R/C brushless motors

    hi Miles, the rotor/magnets is totally hidden. so there won't be a perfect spot that sees "direct flux". i guess the best chance is, place the sensors around the air gap and adjust the orientation of the sensors so that the sensors could see correct polarities from the leakage flux. as for...
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    mounting hall sensors to R/C brushless motors

    Mike, yes, it's totally possible to start your HXT from dead stop with the hall mod, just need a bit of soldering. -george
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    mounting hall sensors to R/C brushless motors

    Jeremy, that makes perfect sense! delta-wye switching should involve 30 deg sensor relocation. for incorrect firing angle, in theory, there're two effects a. different no load speed (which i could not observe with my HXT, i heard it's very motor dependent) and b. torque/A would be harmed if...
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    mounting hall sensors to R/C brushless motors

    Jeremy, is your Tower pro also 12N14P? that's weird, as my HXT is 12N14P too, then our hall sensor positions are quite different, 1/2 slot = off by 105 deg electric angle! hmmmm......i guess one of us is wrong on it, i'll go back and scope it to see the waveform again. -george
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    DIY Brushless Motor?

    hi Paul, i measure 4 numbers - battery V, battery I, output mechanical torque, and output mechanical speed. i checked your post and i also ran into the same kind of problem with my earlier setup. the interaction between the motor and the load was messing up the torque readings. the secret...
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    DIY Brushless Motor?

    i have a delphi alternator converted as the load of a dyno tester. this picture is the dyno i am building and now it's working. http://www.rcgroups.com/forums/attachment.php?attachmentid=2466051 what i was going to say is that....this alternator has stator punch thickness of ~1mm (yes, that's...
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    mounting hall sensors to R/C brushless motors

    flipping the sensors is equivalent (almost) to adding an inverter to the output of the sensor, so it is like making 1 to 0 and 0 to 1. your turnigy motor looks identical to mine, so i guess you could simply use my setting of mounting the sensors at the middle of two slots. for example: slot1...
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    mounting hall sensors to R/C brushless motors

    hi all, could anyone please tell me the ebay place to buy the infeneon controllers? i need more controllers to trash now :oops: thanks!, -george
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    mounting hall sensors to R/C brushless motors

    Jeremy, Cool result! now we have two conversion system working :D this is what was i trying to do, but i could not resist the simplicity of blindly trying all combinations :mrgreen: i am building a dyno to test the motors but unfortunately the coupling b/t the motor and the load seems to...
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    mounting hall sensors to R/C brushless motors

    hi Jeremy, maybe you've figured this out. in case you haven't: sensors in the slots or at the middle of two lost? => i think this is really determined by the motor design, for my case, it's 12N14P and the sensors are at the middle of two slots. if you're totally unsure about this, you could...
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