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Thread: Difference between sensored and sensorless motors?

          
   
   
  1. #1
    New BYT Member Burtech1's Avatar
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    Default Difference between sensored and sensorless motors?

    Aside from the obvious, what is the difference between the sensored and sensorless motors? I imagine it has something to do with having feedback from the motor, but what are the advantages, etc., of the various set ups?

  2. #2
    BYT official flamer of noobs suicideneil's Avatar
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    Default Re: Difference between sensored and sensorless motors?

    Sensored motors & escs use something called Hall-effect sensors to detect where the rotor ( magnets ) is inside the motor, and send this data back to the esc via the sensor wires, allowing the esc to control the motor's rotation and speed precisely. The downside is that there is lag between the sensor signal arriving at the esc and the esc turning the phases on & off in sequence to spin the motor- the extra wires and hardware is also more vulnerable to damage and adds weight/ takes up space.

    Sensorless motors & escs use something called 'back-EMF', where by the esc detects the rotor's position by receiving & interpreting feedback current generated by the motor as the rotor spins inside it and generates EMF pulses. The disadvantage is that this sometimes leads to low-speed cogging as there isnt much EMF for the esc to receive, making it hard for the esc to 'see' where the rotor is- amount of cogging depends on how good the firmware is mainly- castle creations have pretty much perfected sensorless setups, few escs will be smoother these days ( maybe only the german brand Schulze, but they are $$$$$ and have poor customer service + go up in flames alot ).

    Some escs like the MMPro are hybrid escs which can use the sensors to start the motor up perefectly and then switch over to sensorless mode once the motor is spinning ( see: great software )- other escs are sensored-only and cannot work if the sensor wires are unplugged ( novak hvmaxx/ hvpro for example ).

    Reading material & diagrams:

    http://www.stefanv.com/rcstuff/qf200212.html

    In the event this site is down, go here instead: http://suicideneil.00server.com
    Flaming noobs since June '06

  3. #3

    Default Re: Difference between sensored and sensorless motors?

    Cookie for you Neil
    YOUR BRUSHLESS OR NITRO MAY BE FAST
    BUT MY 5B/T IS A HEAVY LOUD PIG

    ~~~~~

    Beating My Truck Not A Rite
    A
    Responsabilty

    RC SPEED CACULATOR

  4. #4
    Gold Level BYT Member michael_lambert's Avatar
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    Default Re: Difference between sensored and sensorless motors?

    it all comes down to your application... I liked Non sensored for most stuff... However a sensored motor is awesome when it comes to crawlers
    Michael Lambert
    Kyosho America | Reds Racing USA | Team Orion | JConcepts | Peak Racing Products | Sprucewood Leasing | Pinnacle hobby | Northern RC
    TKi3 | RB6 | ST5 | Ultima SC


  5. #5
    BYT Life Member E-savage's Avatar
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    Default Re: Difference between sensored and sensorless motors?

    Why you need brushless in a crawler is beyond me... I have a novak ballistic sensored, and my 2030kv savage motor with isnt, and i cant tell a difference between sensored and sensorless, im using the MMP tho...

  6. #6
    New BYT Member Burtech1's Avatar
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    Default Re: Difference between sensored and sensorless motors?

    Interesting, I was wondering how they got feedback with out an encoder. Were they ever used for r.c. motors?

  7. #7
    Gold Level BYT Member michael_lambert's Avatar
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    Default Re: Difference between sensored and sensorless motors?

    Quote Originally Posted by E-savage View Post
    Why you need brushless in a crawler is beyond me... I have a novak ballistic sensored, and my 2030kv savage motor with isnt, and i cant tell a difference between sensored and sensorless, im using the MMP tho...
    Run brushless just like any other application.. Less maintance required, no replacing brushes.. and its really nice having some serious wheel spin when you need it
    Michael Lambert
    Kyosho America | Reds Racing USA | Team Orion | JConcepts | Peak Racing Products | Sprucewood Leasing | Pinnacle hobby | Northern RC
    TKi3 | RB6 | ST5 | Ultima SC


  8. #8
    Gold Level BYT Member michael_lambert's Avatar
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    Default Re: Difference between sensored and sensorless motors?

    Quote Originally Posted by E-savage View Post
    Why you need brushless in a crawler is beyond me... I have a novak ballistic sensored, and my 2030kv savage motor with isnt, and i cant tell a difference between sensored and sensorless, im using the MMP tho...
    Run brushless just like any other application.. Less maintance required, no replacing brushes.. and its really nice having some serious wheel spin when you need it
    Michael Lambert
    Kyosho America | Reds Racing USA | Team Orion | JConcepts | Peak Racing Products | Sprucewood Leasing | Pinnacle hobby | Northern RC
    TKi3 | RB6 | ST5 | Ultima SC


  9. #9
    New BYT Member Burtech1's Avatar
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    Default Re: Difference between sensored and sensorless motors?

    I agree, power is good!

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