| 摘要 |
<p>A controller for controlling a motor and other functions in a commercial door or barrier operator is described. The controller includes a unique motor start circuit for starting an AC motor which employs two dual-pole-dual-throw (DPDT) relays for activating the start coil in combination with a single triac for activating the main coil of the motor, eliminating dv/dt sensitivity. A motor start control for a door or barrier operator includes a speed governor integrated onto the controller for detecting when to shut off AC power to the start coil in a single phase motor. The integrated speed governor uses an RPM sensor for detecting the speed of the operator's limit shaft coupled to software run by the processor. Switches for operating open, close, stop and learn functions are located on the controller to facilitate installation, maintenance and programming by a service provider at the door operator. In addition, a cycle counter provides a warning when the number of barrier movements equals a predetermined, programmable number of movements.</p> |
