Load switching involves holding switching voltage constant until switch-off time if load current falls or remains constant during first time interval, reducing if load current increases

摘要

The method involves switching a switching voltage suddenly to a first predetermined voltage corresponding to the rated load voltage, detecting the load current in a first time interval, holding the voltage constant until a switch-off time if the load current falls or remains the same during the time interval, and performing sudden or timed reduction of the switching voltage to a maximum value if the load current increases during the time interval. Independent claims are also included for the following: a circuit for implementing the method and a digital output unit for a speech programmable controller.