Contactor Detection Circuit

Abstract

The present invention discloses a contactor detection circuit. The contactor detection circuit comprises: a comparator; a reference voltage generation circuit, whose output end is connected to the inverting input end of the comparator, for inputting a reference voltage V1 to the inverting input end of the comparator; a sampling circuit electrically connected to two static contacts of a contactor and its output end connected to the in-phase input end of the comparator, for inputting a sampling voltage V2 to the in-phase input end of the comparator; and a waveform generator, whose output end is connected to the input end of the sampling circuit, is used to input a periodically changing voltage signal V3 to the sampling circuit. When the contactor is in an open state, the sampling voltage V2 output by the sampling circuit is a periodic waveform, causing the comparator to output a periodic square wave signal; when the contactor is in a closed state, the sampling voltage V2 output by the sampling circuit is higher than the reference voltage V1, causing the comparator to output a high level. The present invention does not require the use of isolated power supplies and isolated operational amplifiers, nor does it require the use of MCUs or the development of specialized software, greatly reducing costs.

Dependencies are inferred from the claim text.