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What it is MQTT?

 MQTT is an acronym for Message Queuing Telemetry Transport. It is a lightweight, publish-subscribe, machine to machine network protocol for message queue / message queuing service1. It is designed for connections with remote locations that have devices with resource constraints or limited network bandwidth, such as in the Internet of Things (IoT) . MQTT was created by Andy Stanford-Clark (IBM) and Arlen Nipper (then working for Eurotech, Inc.) in 1999. It was used to monitor oil pipelines within the SCADA industrial control system 1. The goal was to have a protocol that is bandwidth-efficient, lightweight and uses little battery power, because the devices were connected via satellite link which, at that time, was extremely expensive. MQTT is based on a client-server architecture, where a message broker acts as a server that receives all messages from the clients and then routes the messages to the appropriate destination clients . MQTT uses a publish-subscribe model, where clients can

How to choose single chip microcomputer or PLC in the field of industrial control

 Choosing between a single chip microcomputer and a PLC for industrial control applications depends on a number of factors, including the complexity of the control system, the required level of reliability and robustness, the cost constraints, and the required speed and accuracy of control. Here are some general guidelines to consider: Control system complexity: If the control system is relatively simple, with a limited number of inputs and outputs and basic logic requirements, a single chip microcomputer may be sufficient. However, if the control system is complex, with a large number of inputs and outputs, complex logic requirements, and the need for real-time operation, a PLC may be a better choice. Reliability and robustness: PLCs are designed for industrial control applications and are built to withstand harsh environments, including temperature extremes, humidity, and electrical noise. Single chip microcomputers may not be as robust and may not be able to withstand the same level

The difference between PLC and microcontroller?

 PLCs and microcontrollers are both types of programmable electronic devices, but they are designed for different applications and have different characteristics. Application: PLCs are typically used in industrial control applications to automate manufacturing processes, while microcontrollers are used in a wide range of applications, including consumer electronics, robotics, and automotive systems. Programming language: PLCs are typically programmed using ladder logic or other programming languages that are specifically designed for industrial control applications. Microcontrollers are programmed using a wide range of programming languages, including C, C++, and assembly language. Input/output: PLCs typically have a large number of input/output (I/O) points, which allow them to interface with a wide range of sensors and actuators. Microcontrollers typically have a smaller number of I/O points, but can be used with external peripherals to expand their capabilities. Real-time operation:

Siemens PLC Family History

 Siemens PLC refers to both a company and a product line. The company Siemens PLC is a subsidiary of Siemens AG, a global technology and telecommunications corporation based in Germany. The product line Siemens PLC consists of programmable logic controllers (PLCs) that are used for industrial automation and control. According to web search results123, here are some key points about Siemens PLC family history: The Siemens family: The origins of Siemens AG can be traced back to 1847, when Werner von Siemens and Johann Georg Halske founded a telegraph company in Berlin. The company expanded into various fields such as electric power, railways, lighting, medical technology and communications. The Siemens family played a prominent role in the development of the company and its innovations. Some notable members include Ernst Werner von Siemens (the founder), Carl Wilhelm von Siemens (his brother who expanded the business internationally), Wilhelm von Siemens (his son who pioneered wireless t

How to choose a low-end PLC?

 A PLC (programmable logic controller) is a device that can control and automate industrial processes and machines. A low-end PLC is usually cheaper, smaller and simpler than a high-end PLC, but it may have less features, memory and performance. Some factors to consider when choosing a low-end PLC are: Your application requirements: What kind of tasks do you want the PLC to perform? How many inputs and outputs do you need? How fast and accurate do you need the PLC to be? How complex is your logic program? You should choose a PLC that can meet your minimum requirements without wasting resources or money on unnecessary functions. Your budget: How much can you afford to spend on a PLC? Low-end PLCs vary in price depending on their brand, model and specifications. You should compare different options and look for discounts or promotions. You should also consider the total cost of ownership, including installation, maintenance and upgrades. Your compatibility: How well does the PLC work wit

The Method and Process of Siemens PLC Hardware Configuration

 The hardware configuration of Siemens PLC can usually adopt the following methods and processes: Determine control tasks and system requirements: Before hardware configuration, it is necessary to clarify the tasks and requirements of the control system, including the requirements for input and output points, control accuracy, speed, and safety. Select the PLC model and module: According to the control task and requirements, select the appropriate PLC model and module, including CPU, I/O module, communication module, power supply module, etc. Assemble the cabinet and install the modules: According to the selected PLC model and module, assemble the cabinet and install the modules, pay attention to the installation sequence, cable wiring, wiring method, etc. Connect the input and output devices: connect the input and output devices with the input and output modules of the PLC, you need to pay attention to the correctness, stability and safety of the wiring. Perform software configuration

Choice of PLC programming language

 The choice of PLC programming language generally depends on specific application scenarios and personal preferences. PLC programming languages are usually divided into the following categories: Instruction list (Ladder Diagram, LD): a graphical programming language similar to electrical circuit diagrams, easy to understand and learn, and suitable for scenarios with relatively simple control logic. Function Block Diagram (FBD): Program logic is realized through the connection and combination of function blocks, which is suitable for scenarios with complex control logic. Statement List (Structured Text, ST): A textual programming language similar to a high-level programming language, suitable for scenarios that require complex calculations and data processing. Sequential Function Chart (SFC): Represents program logic in the form of a state machine, suitable for scenarios that require complex program control and state transitions. Process and Instrumentation Diagram (P&ID): It is use