Self-checking circuit of preventing misoperation of wiring and working method thereof

Abstract

A self-checking circuit of preventing a misoperation of wiring comprises an alternating current power supply, an alternating current / direct current (AC/DC) convertor, a sensor, a relay and a programmable control unit. The self-checking circuit of preventing the misoperation of the wiring is characterized by further comprising a detecting switch K1 which is connected between the sensor and an electrical level input end of the programmable control unit. The working method of the self-checking circuit of preventing the misoperation of the wiring comprises power supplying, triggering, the opening of a normally-closed switch and judging. The self-checking circuit of preventing the misoperation of the wiring has the advantages of guaranteeing the correctness of signal transmission, improving the reliability of the using of the self-checking circuit of preventing the misoperation of the wiring and the safety of equipment, and being simple, stable and reliable in structure; the kinds and the number of electronic elements are small, and the self-checking circuit of preventing the misoperation of the wiring is convenient to achieve; and the self-checking circuit of preventing the misoperation of the wiring is strong in generality, can be used on sensors of any kind, and can run stably and reliably.

Description

(1) Technical field: [0001] The invention belongs to the field of electrical control, in particular to a self-test circuit for preventing wiring misoperation and its working method. (2) Background technology: [0002] With the rapid development of China's industrial automation and the continuous improvement of sensor intelligence, more and more sensors are used in various related fields, and the resulting security issues have attracted more attention. [0003] In the current known technology, the use circuit of the sensor is generally (see figure 1 ): The sensor is directly connected with programmable control units such as PLC, single-chip microcomputer, frequency converter, DSP, etc., and the sensor directly transmits the detected signal to the programmable control unit, and then the programmable control unit processes the signal, thereby further The control equipment completes the action. Using this connection circuit, if misoperation such as misconnection or short circui...

AI Technical Summary

Problems solved by technology

[0003] In the current known technology, the use circuit of the sensor is generally (see figure 1 ): The sensor is directly connected with programmable control units such as PLC, single-chip microcomputer, frequency converter, DSP, etc., and the sensor directly transmits the detected signal to the programmable control unit, and then the programmable control unit processes the signal, thereby further The control equipment completes the action. Using this connection circuit, if misoperation such as misconnection or short circuit occurs, the sensor is always in the trigger mode, so that the real signal detected by the sensor cannot be transmitted to the programmable control unit, and the safety circuit does not work. , there is a great potential safety hazard, even endangering the safety of personnel

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