| 摘要 |
<p>The forward/reverse logic responds to a controlled reduction of the supply due to a speed control so that upon reduction to a set value, below a threshold corresponding to the stalled motor condition, the logic causes the direction of rotation to reverse. For an electronically commutated motor, when the speed control input (P 14) falls below a threshold (VREF9), a bistable arrangement (D13, D14) changes state so as to invert the counting sequence of the control circuit and reverse the motor which will recommence rotation in that direction upon increase of the speed control beyond the stall position. The device may be used in a control for a ceiling fan. <IMAGE></p> |
