Switching value output module with safe function and diagnosis processing method

Abstract

The invention discloses a switching value output module with a safe function. The switching value output module comprises a CPU unit and a first / second output unit coupled with the CPU unit, the first / second output unit comprises a logic circuit, a driving circuit, a return detection circuit and an output switch which are coupled in sequence, and a power supply voltage detection circuit coupled with the driving circuit, and the power supply voltage detection circuit is used for detecting the power supply voltage of the driving circuit and sending a control signal to the logic circuit of the other output unit based on the detection voltage; the invention further discloses a diagnosis processing method of the switching value output module based on the function safety, the output of the output switch can be controlled on the basis of output switch fault diagnosis, communication diagnosis, CPU unit internal fault diagnosis, power supply fault diagnosis and line fault diagnosis results, and therefore safety is guided; and a double-channel interaction design is added, so that the safety performance is improved, the development cost is reduced and the product size is reduced while the function safety is met.

Description

technical field [0001] The invention relates to the field of industrial automatic control, in particular to a functionally safe switch output module and a diagnostic processing method. Background technique [0002] The switch output control system in the industrial field is the most important input component in industrial control systems such as DCS and SIS. Most of the switching output modules related to functional safety in the prior art adopt 2003 architecture, which often requires a lot of hardware to build and realize. Products designed according to this architecture generally have high cost and large volume. When installation space and cost are required, 2003 architecture products will have limitations. [0003] With the maturity of technology, SIS product design is moving towards the direction of smaller size and lower cost, and more designs start to adopt 1OO2D, 1OO2 or 1OO1D and other architectures. [0004] The Chinese invention patent "A 1002D Functional Safety ...

AI Technical Summary

Problems solved by technology

This design adds a diagnostic unit on the basis of a CPU unit controlling an output unit. The diagnostic unit and the output unit control a switch respectively. The two switches are connected in series. The diagnostic unit can diagnose the output unit and send information to the CPU at the same time. In the event of a fault, turning off the switch it controls leads to safety, but if the diagnostic unit itself fails and cannot provide reliable diagnostic information to the CPU, the entire module has a potential safety hazard

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