A dcs/plc signal interlocking control circuit

Abstract

The invention discloses a DCS / PLC signal interlocking control loop, comprising: a first switch K1 connected to a power supply is connected to one end of the first power line, a second switch K2 is connected to one end of the second power line, and a third switch K3 Connect with one end of the third power line, the other end of the first power line is connected with the first input end of the AC contactor KM1, the other end of the second power line is connected with the second input end of the AC contactor KM1, the third power supply The other end of the line is connected to the second input terminal of the AC contactor KM1, and the first output terminal, the second output terminal and the third output terminal of the AC contactor KM1 are all connected to the motor. Applying the present invention, it is used in the case of dual power supply switching on the power supply side, and when the power supply is restored, the DCS / PLC does not issue a chain jump command, so that the electrical equipment has the prerequisite for automatic restart, thereby ensuring the continuous operation of production, and Ensure that the DCS / PLC chain trip command is issued smoothly during normal shutdown or normal protection action tripping, which will not affect the protective shutdown of the system and will not cause the accident to expand.

Description

Technical field [0001] The present invention belongs to the technical field of industrial control, and more particularly to a DCS / PLC signal chain control loop. Background technique [0002] With the development of computer technology, communication technology and control technology, the traditional control field is experiencing an unprecedented change and has begun to develop in the direction of the network. For large data, high-rate transmission, such as images, speech signals, has spawned the combination of Ethernet and control networks that currently in the commercial field. The network of industrial control systems will integrate various popular technology such as embedded technologies, multi-standard industrial control networks, wireless technology, and expand the development space in the industrial control sector, bringing new opportunities. [0003] The development of the control network has gradually tended to open, transparent communication protocols. Although the dev...

AI Technical Summary

Problems solved by technology

But at this time, due to the release of the running signal sent to the DCS / PLC background by the contactor or relay, the inherent program of DCS / PLC will treat this transient fault as a normal fault, and send a chain trip signal, so that the entire system is in a chain trip. vehicles, resulting in large economic losses

[0010] Therefore, in the existing DCS / PLC solidification program, it is impossible to distinguish the operating signals uploaded by the electricity, which are disconnected due to power transient faults, and which are disconnected due to normal faults, and can only be disconnected according to the specific operating signal. It automatically runs its inherent control program according to the status, which makes the working condition that can continue to run become the working condition of stopping, which greatly affects the continuous production

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