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Low rpm motor and heating element in 250 W

  1. Jan 3, 2016 #1
    i wanted to know if it's possible to run a heating coil which reaches some 300 C and a dc motor of low rpm of some 10 or so.....and all this under 250 W??
  2. jcsd
  3. Jan 3, 2016 #2


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    Yes, both are very much possible. It's a matter of power. You can reach thousands of degrees with low power, a standard flash light bulb does exactly that.
    If you tell us what you're wanting to do we can help more.
  4. Jan 3, 2016 #3


    Staff: Mentor

    As a point of reference, my soldering iron uses only 40 watts.

    But you must ask about heating load, not just the temperature.

    A heater in air can glow white hot, but put it in water and it can't warm to more than 100C.
  5. Jan 4, 2016 #4


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    The filament in a lightbulb gets quite hot.
  6. Jan 5, 2016 #5


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    When things have settled down into equilibrium, the temperature of your device produces the same amount of power loss to the surroundings as the power being supplied. For the same amount of dissipated power, a small object will get hotter than a large object because its surface area will be smaller.
    A human body is radiating several hundred Watts but the surface temperature is only around 30°C - because of radiation of heat and sweating.
  7. Jan 6, 2016 #6


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    Kind of a meaningless question as framed. Could just as easily be "What can one do with 250 watts, a motor, and a heating coil ?"
    You can drive a little motor at 1000 rpm and a tiny heating coil to 1000C with just a few watts.

    If you figure out how much power your heater needs and how much power your motor needs, then you have your answer.

    If you tell us what you are trying to do (what you want to heat, how much torque your motor needs) then we can help to calculate the power required to accomplish the tasks.
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