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Simple control circuit for a dc motor to power a conveyor for 5 seconds

  1. Dec 3, 2011 #1
    I am a hobbyist, and I am not too familiar on to how to run motors. Can someone help me design a simple circuit that drives a dc motor on pulley drive of a conveyor belt. I only need a steady speed, im not changing speeds. The conveyor belt has to stay on for 5 seconds after a switch is turned on. The belt is about 48 inches long, the radius of the pulley is 1 inch. I have calculated the power at the pulley to be 2.6 Watts.
    Thank you in advance,
  2. jcsd
  3. Dec 4, 2011 #2
    The speed of a motor is primarily dependent on the voltage. The torque of a motor is dependent on the current the motor draws. Since there is some resistance in the motor, that resistance will drop a small voltage depending on the current through the motor. This means that even if you supply constant voltage to a DC motor, its speed will drop slightly due to the increased current needed for an increased load.

    Simple motor controllers where precise speed control is not needed just supply constant voltage to the motor. If precise speed control is needed then the current through the motor is also sensed and is used to increase the voltage to the motor to compensate for the voltage lost to motor resistance.
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