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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...

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 l...

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 operat...

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 wirele...

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...

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 configura...

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...

differences between PLCs and DCS

 PLC and DCS are two different types of control systems that are used in industrial automation applications. While both systems are used to control and monitor industrial processes, they have some important differences in terms of their design, function, and application. Design: PLCs are designed as standalone controllers that can be used to control a single machine or process. They are typically used for discrete control applications, such as controlling motors, sensors, and other devices in a manufacturing process. DCS, on the other hand, are designed as distributed control systems that can be used to control and monitor multiple processes or machines across an entire plant or facility. They are typically used for process control applications, such as controlling temperature, pressure, and flow in a chemical plant or oil refinery. Function: PLCs are typically used for discrete control applications, where the process involves discrete events or steps, such as moving a conveyor bel...

Commonly used PLC protocols

 There are several commonly used PLC protocols, including Modbus, Ethernet/IP, Profibus, DeviceNet, and CC-Link. Here is a brief comparison of these protocols: Modbus: Modbus is a serial communication protocol used to connect PLCs to other devices such as sensors, instruments, and HMIs. It is a simple and reliable protocol widely used in industrial automation applications. The maximum transmission speed of Modbus is 115.2 kbps, and a single network can support up to 247 devices. Ethernet/IP: Ethernet/IP is an industrial protocol based on standard Ethernet technology. It is a high-speed protocol that can transfer data at speeds of up to 100 Mbps or more. Commonly used for real-time control and monitoring applications, Ethernet/IP can support up to 64,000 nodes on a single network. Profibus: Profibus is a digital communication protocol used to connect PLCs to other devices such as sensors and actuators. It is a high-speed protocol that can transfer data at speeds up to 12 Mbps. Commo...

PLC brands commonly used in the United States

 There are several PLC brands available in the United States. Some of the most popular brands are: Allen-Bradley: Allen-Bradley is a brand of Rockwell Automation and is one of the most popular PLC brands in the United States. It is known for its reliability, scalability, and ease of use. Siemens: Siemens is a German-based company that manufactures PLCs and is also popular in the United States. Siemens PLCs are known for their high performance and flexibility. GE: GE is an American multinational conglomerate that produces PLCs. GE PLCs are known for their reliability and ease of use. Schneider Electric: Schneider Electric is a French-based company that produces PLCs and is also popular in the United States. Schneider Electric PLCs are known for their high performance and flexibility. AutomationDirect: AutomationDirect is an American company that produces PLCs and is known for its low-cost, high-quality products. The performance of these PLC brands can vary depending on the applicati...

Learning PLC programming as an old electrician

 Learning PLC programming as an old electrician can be challenging, but it is definitely achievable with the right approach and mindset. Here are some tips that can help: Get familiar with the basics: Start by familiarizing yourself with the basic concepts of PLCs and ladder logic programming. Read books and online resources, and attend training courses or workshops. Find a mentor: Consider finding a mentor who can guide you through the learning process and provide practical insights and advice. You can also join online communities and forums where you can connect with other electricians and PLC programmers. Practice and experiment: The best way to learn PLC programming is through hands-on practice. Start by experimenting with simple programs and gradually move on to more complex ones as you gain confidence. Take advantage of online resources: There are many online resources available that can help you learn PLC programming, including video tutorials, online courses, and forums. Ta...

Is PLC ladder diagram easy to learn?

 PLC ladder diagram is one of the most commonly used programming languages in industrial automation. It is a graphical representation of the program logic that allows the programmer to develop complex control algorithms using simple ladder logic diagrams. Whether ladder diagram is easy to learn depends on an individual's background and experience in programming and industrial automation. If you have some basic understanding of programming concepts and electrical circuits, then learning ladder diagram programming may be relatively easy for you. Ladder logic is based on Boolean algebra, and the ladder diagram symbols resemble electrical circuit symbols, making it easier to understand for those with an electrical background. Another advantage of ladder diagram programming is that it is visual, making it easier to understand and troubleshoot than other programming languages. Ladder diagram programming also allows for easy modification and updating of control programs, making it suitabl...

A Clear Introduction to Delta Family PLC

 Delta Electronics is a Taiwanese company that manufactures a wide range of industrial automation products, including Programmable Logic Controllers (PLCs). Delta's PLC product line, known as the DVP series, includes several PLC families ranging from small, cost-effective units to larger, more advanced models. DVP series PLC is known for its user-friendly programming software and high performance. PLCs use the ladder logic programming language and are suitable for small to medium automation projects. Below are some main series of Delta PLCs: DVP-SS Series: The DVP-SS Series is a cost-effective PLC series offering up to 32 I/O points. Compact and easy to install, these PLCs are suitable for small automation projects. The DVP-SS Series offers multiple communication options including RS-232, RS-485 and Ethernet. DVP-SA Series: The DVP-SA series is a mid-range PLC series offering up to 128 I/O points. These PLCs are suitable for medium-sized automation projects and offer advanced featu...

There are also many PLC manufacturers in China, let’s make a comparison

 China has several local PLC manufacturers, such as Delta, Fatek, and Shihlin Electric, among others. Here is a comparison of these Chinese PLC brands with some popular international PLC brands: Delta: Delta is a popular Chinese PLC brand that is known for its cost-effectiveness and wide range of products. It offers a variety of PLC models, including the DVP-SS, DVP-SA, and DVP-SE series. Delta PLCs use a ladder logic programming language and are suitable for small to medium-sized automation projects. Delta PLCs are widely used in industries such as packaging, material handling, and textiles. Fatek: Fatek is another Chinese PLC brand that is known for its cost-effectiveness and user-friendly software. It offers a variety of PLC models, including the FBs series, FB series, and the FBs-PLC series. Fatek PLCs use a ladder logic programming language and are suitable for small to medium-sized automation projects. Fatek PLCs are widely used in industries such as packaging, food processin...

Is it necessary to learn all Japanese PLCs? how is the difference?

 It is not necessary to learn all Japanese PLCs (Programmable Logic Controllers) as each brand and model of PLC has its own unique features, programming language, and capabilities. However, having knowledge of the popular Japanese PLC brands can be beneficial, especially if you work in industries where these PLCs are widely used. The most popular Japanese PLC brands are Mitsubishi, Omron, and Keyence. Each of these PLC brands has its own programming software, language, and capabilities. Therefore, it is essential to have an understanding of each brand's strengths and weaknesses to choose the appropriate PLC for your project. For example, Mitsubishi PLCs are widely used in the automotive industry and are known for their advanced motion control capabilities. Omron PLCs are widely used in the pharmaceutical industry and are known for their advanced safety features. Keyence PLCs are widely used in the semiconductor and electronics industry and are known for their high-speed processing ...

Which Siemens PLCs are easy to learn?

 Siemens PLCs (Programmable Logic Controllers) are widely used in the automation industry and are known for their reliability, flexibility, and ease of use. However, some models are easier to learn than others, especially for beginners. The Siemens S7-1200 is considered the best Siemens PLC for beginners due to its simplicity and easy-to-use software. It is a compact and modular PLC that is ideal for small to medium-sized automation projects. The S7-1200 uses the Step 7 Basic programming software, which is user-friendly and easy to navigate. It also has a range of communication options, including Ethernet and Profibus, making it easy to integrate into your automation system. Another Siemens PLC that is easy to learn is the S7-200. Like the S7-1200, it is compact and modular, making it ideal for small to medium-sized projects. The S7-200 also uses the Step 7 Micro/Win programming software, which is easy to learn, even for those with limited programming experience. In summary, the Si...

Which type of PLC is better to start learning from?

 When it comes to learning PLC (Programmable Logic Controller), there are many types and brands available in the market. However, the most popular and widely used PLC brands are Siemens, Allen Bradley, Mitsubishi, and Omron. As a beginner, it's best to start with a brand that is widely used in your industry or the one you have access to. This will help you gain practical experience and knowledge in the specific systems you'll be working with. However, if you're not working in a particular industry yet or don't have access to a specific brand, I would suggest starting with Allen Bradley. Allen Bradley is one of the most widely used PLC brands globally, and many resources are available online to help you learn the basics. Allen Bradley PLCs use ladder logic programming language, which is easy to learn, and its software, Studio 5000, is user-friendly and widely available. Additionally, Allen Bradley offers many online resources, training courses, and documentation that can...

How to quickly learn automation control technology?

 Learning automation control technology requires a combination of theoretical knowledge and practical experience. Here are some tips to help you quickly learn automation control technology: Start with the basics: Before diving into advanced topics, it's essential to understand the basic concepts of automation control technology. Familiarize yourself with terms such as PLC (Programmable Logic Controller), HMI (Human-Machine Interface), SCADA (Supervisory Control and Data Acquisition), and DCS (Distributed Control System). Learn through online resources: There are numerous online resources available that offer free and paid courses, tutorials, and videos to learn automation control technology. Some popular online learning platforms include Udemy, Coursera, and edX. Join automation control forums and communities: Joining online communities can help you get in touch with experienced professionals who can offer advice and insights into the field. You can also learn from others' expe...

Proportional Valve and Servo Valves

 The use of electronics in today’s technology has increased in controlling various actuating systems such as hydraulic and pneumatic systems in process industries and has naturally led to greater in interest in servo and proportional valves. Both these servo valves and servo proportional valves are electrohydraulic and electro-pneumatic continuously acting type valve that transforms a varying analog or digital input signal into a step less output signal. This signal may be a flow or pressure signal. These Servo valves and Servo-Proportional Valves are electrohydraulic valves, These are continuously acting valves that transform a changing analog or digital input signal into a step-less hydraulic output (flow or pressure). The term servo valve defines a valve design that consists of a bushing spool assembly Indicated by high-precision metering edges. Basically, the name servo valve relates to the term servomechanism, which means that the valve is constantly monitored to control its m...

Fiber Optic Cable vs Coaxial Cable

 Fiber optic cables and coaxial cables are used in various applications. But many of us are still not having proper knowledge about fiber optic cable and coaxial cable. So, today in this article we will discuss the difference between fiber optic cable and coaxial cable. Comparison of Fiber Optic and Coaxial Cables The following are the main comparison between fiber optic and coaxial cables. Physical Construction Material of Construction Transmission Method Bandwidth Transmission Speed Efficiency Diameter Weight Installation Complexity Cost Uses Physical Construction Fiber optic cable is made of the core which is a fiber core. Outside the fiber core, a cladding is present. Cladding is protected by a coating and a strength membrane. This whole assembly is protected by an outer jacket. Coaxial Cable is made up of conductors which are protected by insulators and sheath/shield and outer cover. Material of Construction Fiber optic cable is made up of plastics and glass. While coaxial cab...