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Introduction: RS-485 is a standard protocol for transmitting data. It can be used to establish a reliable, high-speed, real-time, multi-node data communication network connection. RS-485 is also called TIA-485. RS-485 is a standard that defines the electrical characteristics of drivers and receivers used in serial communication systems. RS485 is widely used in industrial control systems and can handle up to 32 devices on a single network. RS-485 is commonly used in industrial automation to monitor and control PLCs, variable frequency drives, DCS, etc. This article will mainly introduce the basic principles, characteristics, wiring and practical application cases of RS-485 communication.   Basic principles of RS-485 communication: RS-485 is an asynchronous serial communication protocol that enables multi-node communication. RS-485 communication is based on differential signaling, where information is transmitted over two complementary signals sent over two wires (often called A and B). The voltage difference between the two wires is what conveys the information, not the voltage between the individual wire and ground. This makes RS-485 systems highly resistant to common mode noise. And it can improve the transmission distance and transmission speed. The RS-485 protocol stipulates that a master node can communicate with up to 32 slave nodes, and the communication between each node is coordinated through the master node.   Features of RS-485 communication: RS-485 communication has the characteristics of high speed, reliability, stability, real-time and low cost. Because RS-485 supports multi-node communication, it eliminates the need for complex signal forwarding mechanisms and makes it easier to expand the network. The RS-485 protocol is standardized, so compatibility issues can be avoided. In addition, due to the application of differential transmission technology, RS-485 communication has high anti-interference capabilities against electromagnetic interference. At the same time, RS-485 communication can ensure the stability and reliability of communication when the communication distance reaches 1.2 kilometers. RS-485 signals are transmitted without acknowledgment. Interruptions or interference in differential signals can corrupt data without being repeated or received; a "fire and forget" system.   RS-485 wiring: The wiring of RS-485 requires the twisted pair mechanism as shown in the figure below. A twisted pair composed of a positive and negative pair of data lines is laid. At the same time, since RS-485 uses differential signals for transmission, we also need to provide an additional common signal ground for the two data lines. In order to avoid interference from other interfering signals, we can add an RS-485 interference-resistant attenuator in the middle of the wiring.   RS-485 communication case: Let's consider a simple example of an RS-485 network with one master and two slave devices. Idle state: When there is no device transmitting, the line is in idle state. In this state, the differential voltage between line A and line B is zero. Master Transmission: When the master wants to send data, it changes the voltage difference between the A and B lines. For example, a "1" might mean that A has a higher voltage than B, and a "0" might mean that B has a higher voltage than A. What the slave will get: All devices on the network, including the slave, will continuously monitor the voltage difference between the A and B lines. When they detect a change, they interpret it as some data. Slave Response: If the master sends a command that requires a response from the slave, the slave will wait until the master completes the transmission and then changes the voltage difference between the A and B lines to send its response. Master Reception: The master device, like the slave device, constantly monitors the voltage difference between the A and B lines, so it will receive the response from the slave device. Return to idle state: After all data has been transmitted, the line returns to the idle state and the voltage difference between lines A and B is zero. In this way, data can be sent back and forth over the RS-485 network. It's important to note that all devices on the network need to use the same logic to interpret voltage differences as bits (i.e. does A having a higher voltage than B represent a "1" or a "0"). In a network with multiple devices, each device needs to have a unique address so that it knows when to listen and when to ignore traffic on the line. This is usually handled by a protocol used over RS-485, such as Modbus or Profibus. For example, in a Modbus network, every message sent by the master begins with the address of the target device. When devices see a message with their address, they know to process the message and possibly send a response. If the address does not match your own address, the message is ignored.   Summarize: Compared with TCP/IP, USB, I2C and other protocols, although the transmission speed of RS-485 is not particularly fast, it has unparalleled advantages: it can realize multi-node communication, has strong anti-interference ability, and has long communication distance. These characteristics are No other protocol can compare. As a communication protocol widely used in industrial control, automation and other fields, RS-485 still has broad prospects for future use.   TZ Tech industrial Automation Hardware supply, Modules, PCB Cards, Drives, Motors, Spare parts, etc.  Many Available just wait for you, feel free to ask to get better deal!!!  Bou L  Sales Specialist [email protected]+86-175 5077 6091  

Today we are going to talk about the American gentleman in our circle - Rockwell Automation.   Largest and Smallest As we all know, Rockwell Automation always evaluates itself as follows: Rockwell Automation is the world's largest company dedicated to industrial automation and information, and is committed to helping customers improve productivity and the sustainable development of the world. Whenever they see Rockwell Automation positioning itself as the world's largest industrial automation and information company, many people will suddenly have this question: Is Rockwell Automation bigger than Siemens, ABB, and Schneider? ? Haha, in fact, what Rockwell Automation calls the largest refers to the largest enterprise focusing on the field of automation compared with other companies operating in multiple fields. However, compared with its competitors at the same level, Rockwell Automation can be said to be the smallest company overall. Today, Rockwell Automation, headquartered in Milwaukee, Wisconsin, USA, has branches in more than 80 countries, currently employs approximately 22,000 people, and achieved global sales of US$6.35 billion as of fiscal year 2013.   Acquisition of AB to focus on customers Rockwell was originally a well-known brand in the United States and a fairly old industrial company. Its qualifications and longevity are comparable to those of General Electric and Emerson Electric. However, unlike these companies that are gradually becoming diversified, Rockwell However, due to the continuous divestiture of businesses in its history (such as Rockwell Collins in the field of avionics), Weill has gradually moved towards a single automation business. In the entire development process of Rockwell, the most important transformation was on February 20, 1985, when Rockwell International acquired Allen- Bradley (In 1903, Lynde Bradley and Dr. Stanton Allen founded the Compression Rheostat Company with an initial capital of $1,000. In 1909, the Compression Rheostat Company was renamed the Allen-Bradley Company. In 1915, Allen-Bradley's sales reached $86,000.) , which also became the largest acquisition in Wisconsin history. After acquiring Allen-Bradley, Rockwell devoted all its efforts to the expansion of automation products and business, and achieved gratifying results relying on the Allen-Bradley brand. AB quickly became Rockwell's core pillar. In 2002, Rockwell International changed its name to Rockwell Automation and continued to trade on the New York Stock Exchange under the code name "ROK". In 2003, the Allen-Bradley brand celebrated its 100th anniversary. For the acquired brand, not only did it not die, but it grew stronger and stronger with the help of the acquirer, and even became its core business. This can also be said to be a rare legendary story.   Limited distribution strategy Rockwell Automation's sales model is also rare in the industry. It adopts a limited distribution strategy and insists on having only one agent in each region for a long time, thus making its distributors, integrators and Rockwell Automation We have maintained a very benign and high-loyal relationship, and we are a very successful model in the field of automation. Currently, Rockwell Automation has 15 authorized distributors, 124 recognized system integrators, more than 30 Encompass strategic partners and global strategic alliances in the Asia-Pacific region in China. As a listed company, the pressure from shareholders drives it to continue to grow, its business must grow, and its profits must grow. In the single automation market, with a market share of more than 60% in the North American market, Rockwell Automation has chosen several directions. It is a process business, one is strategic services, and the other is OEM market. The process business has been defined as the company's largest growth engine.   Technical advantages of complete architecture Among today's mainstream PLC and manufacturing information system suppliers, Rockwell Automation's technology is the best, which is mainly reflected in the completeness, unity and forward-looking nature of its system architecture. For example, Rockwell Automation has unified all PLC controllers on this platform through the launch of the Logix platform. Whether it is ControlLogix, MicroLogix or SafetyLogix, they all have unified programming tools and engineering environments; in addition, the launch of FactoryTalk And the integration with the Logix platform also builds a control system that seamlessly covers from the control layer to the information layer, and is a global information system. Looking back at its major competitors in the industry, the problem of multi-product integration and unification has always been difficult to solve, which has brought many hidden dangers and troubles to users. Moreover, while leading in technology, Rockwell Automation's products have always maintained excellent quality. In the Chinese market, the price of AB brand PLC is high-end, but its reliability, retention of existing customer loyalty and other indicators are generally recognized by the industry.   Many Available just wait for you, feel free to ask to get better deal!!!Bou LSales [email protected]+86-175 5077 6091

What is motion control? Motion control (MC) is a branch of automation, also called electric drag control. Most of its power sources are based on electric motors. In other words, motion control is actually based on electric motors to control changes in physical quantities such as angular displacement, speed, and torque. The application of motion control in the field of robots and CNC machine tools is more complex than that in special-purpose machines because the latter's motion form is simpler and is often called general motion control (GMC). Motion control is widely used in the packaging, printing, textile and assembly industries. Motion control is actually based on electric motors, and the electric motors here refer to servo motors; if only one servo motor is used in a set of stand-alone equipment, in this case it will focus more on the control of the motor, such as position, speed, Torque control; in this example, the control of a single motor is only a part of motion control. Motion control is mainly for products. It can be said to be a motion control system. The system as a whole includes machinery (motors are just spare parts in machinery), electrical, software, etc. It controls and manages the position and speed of mechanical moving parts in real time. , so that it can be transformed into the desired mechanical motion control according to the predetermined control scheme. There are many kinds of motion control systems, but from the basic structure, the hardware of a typical modern motion control system mainly consists of: host computer, motion controller, power drive device, motor, actuator and sensor feedback detection device.   What is automated process control? The principle of automated process control is to use PLC controllers to collect sensor feedback data, and after analyzing and processing these data, adjust, optimize and control various equipment to improve production efficiency. The objects it controls are generally various types of water pumps, fans, electric valves, etc. The entire system generally consists of PLC control cabinet, power distribution cabinet, control program, various sensors, configuration software, monitoring system, etc. Process automation is generally used in environmental protection industries such as sewage and exhaust gas treatment, and energy-saving industries. It intelligently adjusts various load equipment in industrial production to ensure that they operate at their best to achieve energy saving. Mainly used in the field of traditional industrial automation, it is a large system control with many control objects, such as a production line.   Many Available just wait for you, feel free to ask to get better deal!!!Bou LSales [email protected]+86-175 5077 6091

Each type of PLC on the market today has its own functional advantages. PLCs from Rockwell (Allen Bradley) and Siemens (Siemen) are two of the most widely used in the world, but there are many key differences between them. Let us take a look below: Performance and availability Making a decision between the two based solely on performance isn't easy. In terms of speed, reliability and output, they are equally matched. However, factors such as ease of operation and integration are often differentiating points to consider. There's a lot to be said for ease of use and user-friendly interface. Allen-Bradley PLCs are known for possessing both of these qualities, making this programmable logic controller an attractive investment for any manufacturer. Ease of use means that even relatively untried PLC technicians without extensive programming experience can still use Allen-Bradley PLCs—but the ease of use doesn't stop there. Debugging an Allen-Bradley PLC arguably takes less time and effort than using a Siemens PLC. In addition, Allen-Bradley PLCs can communicate efficiently with third-party devices and can import and export tags from Excel to a Human Machine Interface (HMI) or SCADA database. Still, depending on the technician's experience level and the intended application, ease of use is not always the most important criterion. Siemens allows extensive programming and customization of their PLCs to meet specific business needs. Naturally, this means technicians will need a stronger computer programming background to effectively use and maintain Siemens PLCs, but the opportunities this customization presents cannot be underestimated. Hardware While the general consensus is that the Allen-Bradley PLC is the more user-friendly solution of the two, they may fall slightly short in terms of ease of installation compared to the Siemens. When installing an Allen-Bradley PLC, you will also need to connect the Allen-Bradley power supply, rack, and add-in card for the secure communication port. Siemens PLCs, on the other hand, plug into most standard 24V DC power supplies and have built-in secure communication ports. Finally, Siemens PLCs come with built-in protocols according to European standards (ASI, Profinet, Profibus), while Allen-Bradley PLCs come with American protocols (EthernetIP, ControlNet, DeviceNet, etc.). Support Support availability is an important feature to consider when purchasing a PLC. Siemens offers 24/7 after-sales technical support, field services and spare parts for its products every day of the year, including any products falling under its process and factory automation categories. Rockwell also offers year-round 24/7 technical support for its products, but it's not as comprehensive as what Siemens offers, and the level of free support depends on the amount of hardware installed. In either case, the level of support you feel comfortable with may be an important factor in your purchasing decision. Which one is the winner? Sure, it's easy to choose a PLC based on one or more features, but when making a purchasing decision, it's more important to look at the entire package - ease of use and integration, after-sales support, and more. Ultimately, the right PLC is the one that checks the most boxes for a given application. Determining a "winner" based on popularity alone really depends on where you work. Siemens PLC is undoubtedly the most popular in Europe, which makes sense since Siemens AG happens to be the continent's largest industrial manufacturing company. In North America, Rockwell Automation's Allen-Bradley is by far the most popular PLC supplier.

1. Fault-tolerant Ethernet is the control network of PKS. FTE not only provides fault-tolerant features, but also provides fast network response and security for industrial Ethernet control applications. FTE (Fault Tolerant Etherent) Fault-tolerant Ethernet is a single network with a redundant network structure, implemented through Honeywell's FTE driver and commercial network equipment. FTE networks include redundant switches and cables. Topology: Dual parallel tree networks connected at the top. 2. The cascade lines (cross links) between switches form a single network. Commercial network equipment refers to switches, dual-port single network cards or single-port dual network cards. FTE network communication detection screen Detection screen starts 3. The system must consist of a controller, server, and operating station. 4. FTE network includes redundant switches and cables. Tree network: The network formed by connecting to the A port on the A switch is called the A network (yellow tree). The network formed by connecting to port B on switch B is called network B (Green tree). Localhost receives the data node. FLEX operating station (F station): process data and related alarms and events, as well as other data information, come directly from the server; There are two connection methods for configuring ES-F: Fixed connection method (Static): Provides a permanent dedicated connection for a specific ES-F. Rotary connection method (Rotary): Provides an on-demand connection, suitable for when full-time operational access is not required. Console operation station (C station): process data and related alarms and events come directly from the controller; other data information comes from the server; Console Extension operating station (CE): process data and related alarms and events, as well as other data information, all information comes from station C. 7. A C300 controller has two IOLINKs. Each IOLINK supports up to 40 IO cards, and one controller supports up to 64 IO cards. Each set of C300 controller supports up to 64 IO Units (IOU). The C300 controller must be connected to the control firewall. The FTE address of the main controller of the C300 controller is set to an odd number, and the backup controller address is the address of the main controller + 1. Control Firewall (CF9) Control firewall: It appears in pairs in the FTE network, 8+1 ports, of which there is a dedicated network port for upward connection to the switch, and the remaining 8 network ports can be connected to the controller. Function: Refuse to accept all information that the controller does not need. If the communication speed slows down, the flow of unimportant information will be controlled. 8. The C300 controller consists of controller hardware and control software CEE (control execution environment), as shown in the figure: