speed controller for universal motor

Discussion in 'General Electronics Chat' started by gjo, Oct 23, 2013.

  1. gjo

    Thread Starter New Member

    May 22, 2013
    28
    0
    I cant upload a copy of the diagram, so i will do my best to describe it. It is a universal motor with a speed controller. The controller has a potentiometet feeding a capacitor that is used to trigger a diac that turns on the triac. My question is if the rc circut is in series with the motor and parallel with triac, why doesn't the motor run even if triac is shorted open?
     
  2. gjo

    Thread Starter New Member

    May 22, 2013
    28
    0
  3. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    5,773
    1,103
    Because the RC circuit has much too high an impedance for running the motor. Only a small current flows through the motor if the triac is open.
     
  4. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,509
    2,369
    There is not enough current flowing in the snubber to provide sufficient current for the motor.
    Max.
     
  5. gjo

    Thread Starter New Member

    May 22, 2013
    28
    0
    Thanks, that makes sense
     
Loading...