Circuitry for protection against electromotively-induced voltage transients in solid state relay circuits

摘要

In a solid state relay circuit including a power semiconductor for switching power to a load circuit and having circuitry for disabling the power semiconductor to protect against current overload or short circuits, such disabling means including a silicon controlled rectifier for short circuiting the input to the power semiconductor, apparatus for sensing the presence of transient voltages in the load circuit, and apparatus for disabling any short circuit caused by the silicon controlled rectifier due to such voltage transients.