Ac zero-volt switch circuit

Abstract

Abstract PURPOSE: To turn ON the circuit accurately regardless of characteristics of a load without possiblity of a rush current even in case of using a trans load, by generating a trigger pulse by a FF interloking with a power voltage detection circuit and a circuit detecting a voltage between main electrodes of thyristors. CONSTITUTION: A signal is applied to input A and the moment when a clock from voltage detection circuit 29 changes from high to low, the Q output of FF28 causes AND gate 26 to open and trigger pulse generating circuit 27 turns ON thyristor 2. At this time, since gate 26 is opening because of an inductive load, etc., even if the thyristor is turned ON, generating circuit 27 of voltage detection circuit 25 is driven to turn ON element 2 accurately. While no signal is applied to input A, the output Q of FF28 becomes low owing to the rise of circuit 29, and supplying a voltage to the load starts with a constant polarity and ends with the opposite polarity, so that the saturation will be hard to occur even in case of a trans load and no rush current will flow COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Shinichi Iwamoto

Bibliographic Details