Description
3721C Invensys Triconex system
3721C Invensys Triconex system
Module Clips Drive controller servo motor
Contact: Mr. Lai
Wechat:17750010683
Whats app：+86 17750010683
Skype：+86 17750010683
QQ: 3221366881
3221366881@qq.com
What exactly does embedded development do?
Embedded development is a technology similar to programming, but our understanding of the scope of programmers is to do computer software, web development, and also to do apps.
The majority of embedded development is intelligent electronic products, which are designed for hardware programming. This hardware can be understood as a circuit board, usually composed of a controller (processor) chip and different circuits.
The specific program and circuit are generally determined by the product function. For example, an electronic clock product is usually composed of a digital tube and a microcontroller (controller), and then written in C language to download it to the microcontroller to achieve clock display.3721C Invensys Triconex system
Of course, there are far more products that can be developed in embedded systems, including smartphones, wearable devices, drones, robots, mice and keyboards, and so on.
The knowledge system of embedded development and design is also very diverse, and different products require different learning contents.
So, if we want to enter embedded development, we must first understand several directions of embedded development, otherwise you will never find a starting point.
The general mainstream directions are microcontroller development, ARM+Linux development, and FPGA/DSP development.
I have been working on microcontroller development for the past 10 years of my career.
Microcontrollers can be said to be the foundation of all directions. If you have strong microcontroller development capabilities, then ARM+Linux, or FPGA/DSP are easy for you to get started.
The development of microcontrollers is also one of the directions with the lowest threshold for embedded systems. Initially, I was self-taught in electrical engineering and transferred there. It took me about four months from the beginning of my studies to finding a job.
However, at that time, the threshold was still very low, and you could basically find a job by working on a small project with a 51 microcontroller.
If it”s the current situation, you only know these things and have little competitiveness. Nowadays, the main focus of enterprises is on whether you have project experience, rather than what kind of microcontroller you know.
The project experience can be accumulated through practical projects with endless microcontroller programming, which can be said to be the closest to actual development at present.
At present, the salary of single-chip microcontrollers is not low, and it is normal for them to start at 8K in first tier cities, and they can reach 15K after working for 2-3 years.
There are many industries covered by embedded systems, and in the later stage, based on work, we will only focus on one direction. From a macro perspective, we will divide it into embedded software development and embedded hardware development. Software development is mainly based on application software development on systems (Linux, VxWorks, WinCE, etc.), and hardware development includes motherboard design, system porting, cutting, and writing low-level drivers
My personal experience started with microcontrollers. Firstly, I studied C and C++, digital and analog electronics, power electronics, circuit design, microcontroller principles, FreeRTOS, data structures, and computer operating systems. Later, due to work requirements, I relearned university automation control theory, signals and systems, complex functions, linear algebra, calculus, statistics, and compiler principles. These are all basics, and it is important to understand and thoroughly study them, This will bring help to the later research and development work, and there is also a need for more drawing board, drawing board, and practical operation. Without practicing optics, the efficiency is very low, and knowledge is repetitive. Only by repeatedly looking and using can we understand. We can buy some development boards to assist in learning. Now that the internet is developed, network resources can improve our learning efficiency.
Embedded development refers to developing under an embedded operating system, commonly used systems include WinCE, ucos, vxworks, Linux, Android, etc. In addition, develop using C, C++, or assembly; Using advanced processors such as arm7, arm9, arm11, powerpc, mips, mipsel, or operating systems also belongs to embedded development.
1. Basic knowledge:
Purpose: I can understand the working principles of hardware, but the focus is on embedded software, especially operating system level software, which will be my advantage.
Subjects: Digital Circuits, Principles of Computer Composition, and Embedded Microprocessor Architecture.
Assembly Language, C/C++, Compilation Principles, Discrete Mathematics.
Data structure and algorithms, operating systems, software engineering, networks, databases.
Method: Although there are many subjects, they are all relatively simple foundations and most of them have been mastered. Not all courses may be taught, but elective courses can be taken as needed.
Main books: The C++programming language (I haven”t had time to read it), Data Structure-C2.
2. Learning Linux:
Purpose: To gain a deeper understanding of the Linux system.
Method: Using Linux ->Linxu system programming development ->Driver development and analysis of the Linux kernel. Let”s take a closer look, then the main topic is principles. After reading it a few times, look at the scenario analysis and compare it deeply. The two books intersect, with depth being the outline and emotion being the purpose. Analysis is version 0.11, suitable for learning. Finally, delve into the code.
Main books: Complete Analysis of Linux Kernel, Advanced Programming in Unix Environment, Deep Understanding of Linux Kernel, Scenario Analysis, and Source Generation.
3. Learning embedded Linux:
Purpose: To master embedded processors and their systems.
Method: (1) Embedded microprocessor structure and application: Direct arm principle and assembly are sufficient, without repeating x86.
(2) Embedded operating system class: ucOS/II is simple, open source, and easy to get started. Then delve deeper into uClinux.
(3) Must have a development board (arm9 or above) and have the opportunity to participate in training (fast progress, able to meet some friends).
Main books: Mao Decao”s “Embedded Systems” and other arm9 manuals and arm assembly instructions.
Modify the watchdog time of the PROFINET IO device under 16 STEP7
3.2 Check if the installation of PROFINET IO communication equipment meets the specifications
Most cases of PROFINET IO communication interference problems are caused by equipment installation that does not comply with the installation specifications for PROFINET IO communication, such as incomplete shielding, unreliable grounding, and being too close to interference sources. Installation that meets the specifications can avoid communication failures caused by electromagnetic interference. You can refer to the following brief installation requirements for PROFINET:
1. Wiring of PROFINET 3721C Invensys Triconex system
In order to reduce the coupling of electric and magnetic fields, the larger the parallel distance between PROFINET and other power cable interference sources, the better. In accordance with IEC 61918, the minimum distance between PROFINET shielded cables and other cables can be referred to Table 1. PROFINET 3721C Invensys Triconex system can be wired together with other data cables, network cables, and shielded analog cables. If it is an unshielded power cable, the minimum distance is 200mm.
Comprehensive analysis of the principle and application skills of microcontroller IO port
IO port operation is the most basic and important knowledge in microcontroller practice. This article takes a long time to introduce the principles of IO ports. I also consulted a lot of materials to ensure the accuracy of the content, and spent a long time writing it. The principle of IO ports originally required a lot of in-depth knowledge, but here it has been simplified as much as possible for easy understanding. This will be of great help in solving various IO port related problems in the future.
The IO port equivalent model is my original method, which can effectively reduce the difficulty of understanding the internal structure of the IO port. And after consulting and confirming, this model is basically consistent with the actual working principle.
I mentioned a lot earlier, and many people may already be eager to actually operate microcontrollers. The IO port, as the main means of communication between the microcontroller and the outside world, is the most basic and important knowledge for microcontroller learning. Previously, we programmed and implemented an experiment to light up the LED at the IO port. This article will continue to introduce the relevant knowledge of the IO port.
In order to better learn the operation of IO ports, it is necessary to understand the internal structure and related concepts of IO ports. These knowledge are very helpful for subsequent learning, with a focus on understanding and no need to memorize them intentionally. If you don”t remember, just come back and take a look. If you use it too much, you will naturally remember.
We have said that the most accurate and effective way to understand a chip is to refer to official chip manuals and other materials. But for beginners of microcontrollers, it may be difficult to understand the chip manual directly, especially when they see a bunch of English, unfamiliar circuits, and terminology. If it were me, I would definitely be crazy. But here I still provide a picture taken from Atmel”s official “Atmel 8051 Microcontrollers Hardware Manual”.
The purpose of giving this picture is not to dampen everyone”s enthusiasm for learning, but to help everyone understand how the various microcontroller materials we have seen come from and whether they are accurate. All of these can be clarified through official information, which will be helpful for everyone to further learn something in the future.
Introduction to the Second Function
The above figure is the authoritative 51 microcontroller IO port structure diagram provided by the official. It can be seen that the internal structure of the four sets of IO ports of the microcontroller is different, because some IO ports have a secondary function, as mentioned in the introductory section.
Do you remember this pin diagram? The second function name of the IO port is marked in parentheses. Except for P1, each interface has a second function. When introducing the microcontroller system module, I mentioned that the 51 microcontroller has an interface for reserved extended memory, which is the second function of P0 and P1 in the figure (while also using pins such as 29 and 30). Because it is not widely used and involves in-depth knowledge, no specific research will be conducted. By the way, the AD0~AD7 we see here are actually used for parallel ports. The second function of the P3 port, including serial port, will be introduced in detail later.
The drawbacks of network IO and the advantages of multiplexing IO
In order to talk about multiplexing, of course, we still need to follow the trend and adopt a whiplash approach. First, we will talk about the drawbacks of traditional network IO and use the pull and step method to grasp the advantages of multiplexing IO.
For the convenience of understanding, all the following code is pseudo code, and it is sufficient to know the meaning it expresses.
Blocking IO
The server wrote the following code to handle the data of client connections and requests.
Listenfd=socket()// Open a network communication port
Bind (listenfd)// binding
Listen (listenfd)// Listening while (1){
Connfd=accept (listenfd)// Blocking connection establishment
Int n=read (connfd, buf)// Blocking read data
DoSomeThing (buf)// What to do with the data you read
Close (connfd)// Close the connection and wait for the next connection in a loop
}
This code will be executed with stumbling blocks, just like this.
It can be seen that the thread on the server is blocked in two places, one is the accept function and the other is the read function.
If we expand on the details of the read function again, we will find that it is blocked in two stages.
This is traditional blocking IO.
The overall process is shown in the following figure.
So, if the client of this connection continues to not send data, the server thread will continue to block on the read function and not return, nor will it be able to accept other client connections.
This is definitely not feasible.
Non blocking IO
To solve the above problem, the key is to modify the read function.
A clever approach is to create a new process or thread every time, call the read function, and perform business processing.
While (1){
Connfd=accept (listenfd)// Blocking connection establishment
Pthread_ Create (doWork)// Create a new thread
}
Void doWork(){
Int n=read (connfd, buf)// Blocking read data
DoSomeThing (buf)// What to do with the data you read
Close (connfd)// Close the connection and wait for the next connection in a loop
}
In this way, once a connection is established for a client, it can immediately wait for a new client connection without blocking the read request from the original client.
However, this is not called non blocking IO, it just uses multithreading to prevent the main thread from getting stuck in the read function and not going down. The read function provided by the operating system is still blocked.
So true non blocking IO cannot be achieved through our user layer tricks, but rather by imploring the operating system to provide us with a non blocking read function.
The effect of this read function is to immediately return an error value (-1) when no data arrives (reaches the network card and is copied to the kernel buffer), rather than waiting for blocking.
The operating system provides this feature by simply setting the file descriptor to non blocking before calling read.
Fcntl (connfd, F_SETFL, O_NONBLOCK);
Int n=read (connfd, buffer)= SUCCESS;
In this way, the user thread needs to loop through the call to read until the return value is not -1, and then start processing the business.
We noticed a detail here.
Non blocking read refers to the stage where data is non blocking before it reaches the network card, or before it reaches the network card but has not been copied to the kernel buffer.
When the data has reached the kernel buffer, calling the read function is still blocked and requires waiting for the data to be copied from the kernel buffer to the user buffer before returning.
The overall process is shown in the following figure
IO multiplexing
Creating a thread for each client can easily deplete the thread resources on the server side.
Of course, there is also a clever solution. After accepting each client connection, we can put the file descriptor (connfd) into an array.
Fdlist. add (connfd);
Then create a new thread to continuously traverse the array and call the non blocking read method for each element.
While (1){
For (fd “- fdlist){
If (read (fd)!=- 1){
DoSomeThing();
}
}
}
In this way, we successfully processed multiple client connections with one thread.
Do you think this means some multiplexing?
But this is just like using multithreading to transform blocked IO into seemingly non blocking IO. This traversal method is just a small trick that our users have come up with, and every time we encounter a read that returns -1, it is still a system call that wastes resources.
Making system calls in a while loop is not cost-effective, just like making rpc requests while working on distributed projects.
So, we still need to plead with the operating system boss to provide us with a function that has such an effect. We will pass a batch of file descriptors to the kernel through a system call, and the kernel layer will traverse them to truly solve this problem.
Is it better to have a higher number of IO module bit widths?
IO is an important component of PLC, and the collection of PLC information and the output of instructions must be applied to various input and output IO. I don”t know if you have read some IO user manuals. One of their instructions is the device”s bit width, such as 12 bits and 16 bits. So, is it better to have a higher number of bit widths for the IO module? Let”s talk about this matter.
Bit width is the number of bits of data that can be transmitted within a clock cycle, and the larger the number of bits, the greater the amount of data that can be transmitted instantly. From this perspective, the larger the bit width of the IO module, the better. This is not a problem. However, the amount of data transmission, also known as data bandwidth, depends not only on the bit width, but also on the frequency of data transmission. The multiplication of the two is the final total amount of data transmitted. That is to say, even if the light position is wide, but the frequency is too high, it still cannot work. At the same time, the larger the bit width, the higher the hardware cost, and the greater the heat generation and power consumption of the device.
How to Apply Ethernet IO Module to Weighbridge Data Collection3721C Invensys Triconex system
Weighbridge, a large scale set on the ground, usually used to weigh the tonnage of cargo carried by a truck. It is the main weighing equipment used for measuring bulk goods in factories, mines, merchants, etc. The MXXXX series of Ethernet IO modules with barium rhenium technology have rich IO ports that can be used to assist in data collection and transmission of the weighbridge, quickly achieving comprehensive management of data and control.
Before the vehicle enters the weighbridge, there will be an infrared sensor scanning about a few hundred meters. The infrared sensor will output a switch signal to the Ethernet IO module, indicating that a vehicle needs to enter. Before the vehicle officially enters the weighbridge for weighing, there will be an infrared barrier sensor scanning, and the barrier will also output a switch signal to the Ethernet IO module. When the vehicle is completely parked in front of the weighbridge (including whether the position is correct), the central control room will decide whether to start weighing based on the information received by the IO module from the radar sensor. Finally, the vehicle is weighed and drives away from the weighbridge. The scanning signal from the infrared barrier sensor at the exit is transmitted to the IO module, and the central control room controls the IO port of the IO module to open (close) the barrier. The green light will light up, and the vehicle will fully exit and leave the weighing weighbridge. The entire weighing process requires only one Ethernet IO module to collect information and control actions.3721C Invensys Triconex system
The MxxxT industrial remote Ethernet I/O data acquisition module adopts an industrial grade circuit design. The digital input adopts optocoupler isolation, providing 12 pulse counting inputs, supporting dry and wet contact input types. The analog input adopts operational amplifier isolation, supporting 12 bit high-precision data acquisition, compatible with 0~5V, 0~10V, 0~20mA, and 4~20mA input types. The DO output is a transistor Sink output, providing one channel of high-speed pulse output, The thermal resistance RTD input supports two types: PT100 and PT1000, and the analog AO output supports 0-10VDC output.
Pocket Io ™ The development platform has opened up numerous new avenues for experiencing the full power of Industry 4.0.
Compact design: compact structure, ultra small size, and overall dimensions (10 cubic inches: 3.5 “x 3.5” x 0.8 “).
Reliable and safe technology: Composed of advanced industrial products, all products have a rated working environment temperature of -40 ° C to+125 ° C, fully utilizing Maxim”s reliable, safe, and fast demagnetization technology.
Efficient: Ensure low power consumption and improve efficiency – no need for cooling fans.
Integrate numerous powerful interfaces: provide a complete set of 30 IOs for controlling the entire manufacturing node or a certain device, including: 4 analog inputs, 1 analog output, 8 digital inputs, 8 digital outputs, 2 RS-485 (compatible with Profibus fieldbus), 3 encoder/electrical control ports, and 4 IO Link hosts.
Long battery life: Firstly, the compact and portable PLC platform can work for up to 2 hours using “AA/AAA” type batteries, and 8 hours using LiFePO4 rechargeable batteries.
Programmable: It can be programmed through Arduino Sketch or using Intel”s Edison Eclipse IDE tool, supporting Windows, Linux, or Mac OS operating systems.
Easy to use: Sketches can be converted into apps and then downloaded to iPads ® Or iPhone ® (Converted to an HMI panel for controlling Pocket IO).
What are the advantages of Ethernet remote IO modules that can be cascaded?
Advantages and specific application scenarios of Ethernet remote IO modules that can be cascaded
For scenarios where data collection control points are linearly distributed, such as streetlights, bridges, streetlights, digital factories, parking lot parking monitoring, smart parking lots, smart parking racks, and building automation control systems in smart parks, using cascading dual Ethernet remote IO modules saves more costs than using single Ethernet remote IO modules.
The Ethernet remote IO module that can be cascaded is a new type of Ethernet remote IO module that supports MAC layer data exchange and can achieve hand in hand connection. This not only saves switch interfaces, but also reduces a large amount of Ethernet cable costs, wiring space, and wiring costs.
Its advantages are as follows:
1. No need for a large number of Ethernet switches or occupying Ethernet switch ports;
2. It can save a lot of Ethernet cables, cable space, and labor costs for installing cables;
3. The overall cost has significantly decreased;
4. Supports both Modbus RTU protocol, Modbus TCP protocol, and the Internet of Things protocol MQTT protocol;
5. Support TCP Server and TCP Client services;
6. Can be connected to SCADA systems, PLC systems, or cloud platforms;
7. The series uses a MAC layer for data exchange, ensuring that network connectivity does not cause communication issues with subsequent devices due to device failures in the middle.
The comparison between cascaded Ethernet remote IO modules and traditional IO modules used in building automation systems is shown in the following figure:
1. Adopting a cascaded dual Ethernet remote IO module, data acquisition and control wiring for floors with a height of 70 meters only requires a 70 meter Ethernet cable;
2. Using a traditional single Ethernet remote IO module, the data acquisition and control system wiring for a 70 meter high floor requires a 280 meter Ethernet cable.
It can be seen that using cascaded dual Ethernet remote IO modules can save a lot of wiring costs compared to traditional single Ethernet remote IO modules.
What is the difference between remote IO and distributed IO
People often discuss the difference between remote IO and distributed IO. However, some people believe that they are the same and terms can be exchanged, while others believe the opposite. What is the difference between remote I/O and distributed I/O? The following is a guide from remote IO manufacturer Zhongshan Technology to understand the difference between remote IO and distributed IO.
Remote and distributed within the location range.3721C Invensys Triconex system
Today”s DCS is a control system with many distributed autonomous controllers, each with many continuous operations. This controller is bundled together by a central monitoring controller. We have used the terms remote and distributed in the locations of I/O and controllers. It is easy to see how these terms are misunderstood.
From the perspective of PLC, remote I/O represents the actual distance that the I/O module is away from the control PLC. Distributed I/O is very intelligent, as mentioned earlier, remote I/O is sometimes referred to as distributed I/O. Let”s take a look at the definition of distributed I/O. This definition is different from remote I/O.
Generally speaking, distributed I/O has a brain or some computing power. By default, it is remote. As mentioned earlier, remote I/O is located physically far from the control PLC. Remote I/O has no brain and cannot perform any computational functions at all. It can be said with certainty that when you hear the term remote I/O, it only involves one controller or PLC, while distributed I/O has multiple controllers.
ZSR-Ethernet-2184 is a distributed Ethernet RTU that supports 4-way switch digital input (Di), 8-way analog input (Ai), 4-way relay (Do) output, 1-way RS485 serial port data acquisition to Ethernet, and Modbus RTU terminal. Merge 485 to Ethernet serial port server function, support Modbus to TCP/UDP protocol conversion, support virtual serial port, and interface with various configuration software. Supports signal acquisition in the range of 0-5V, 0-10V, 0-30V, or 0-20ma, 4-20ma, with built-in software and hardware watchdog, industrial grade components, and stable operation in an industrial environment of -40~85 ° C.
Building a High Channel Density Digital IO Module for the Next Generation Industrial Automation Controller
There are currently many articles introducing Industry 4.0, and smart sensors are becoming increasingly popular in factory environments (I and other authors have written about these topics). Although we have all noticed a significant increase in the use of sensors in factories, processing plants, and even some newly built automation systems, the widespread use of sensors has also brought about an important change, which is the need to handle a large amount of IO within these old controllers. These IOs may be digital or analog. This requires the construction of high-density IO modules with size and heat limitations.
Usually, digital IO in PLC consists of discrete devices such as resistors/capacitors or independent FET drives. In order to minimize the size of the controller as much as possible and to handle 2 to 4 times the number of channels, this has led to a shift from a separate approach to an integrated approach.3721C Invensys Triconex system
We can use the entire article to illustrate the drawbacks of the split method, especially when the number of channels processed by each module reaches 8 or more. However, when it comes to high heat/power consumption, a large number of split components (from the perspective of size and mean time between failures (MTBF)), and the need for reliable system specifications, it is sufficient to demonstrate that the split method is not feasible.
Figure 1 shows the technical challenges faced in building high-density digital input (DI) and digital output (DO) modules. In both DI and DO systems, size and heat dissipation issues need to be considered.
Design a High Channel Density Digital Input Module
The traditional split design uses a resistive voltage divider network to convert 24V/48V signals into signals that can be used by microcontrollers. The front-end can also use discrete RC filters. If isolation is required, external optocouplers are sometimes used
For example, the current limiting value of DI devices in ADI is 3.5mA/channel. So, as shown in the figure, we use two channels in parallel. If the system must be connected to a Type 2 input, adjust the REFDI resistance and RIN resistance. For some newer components, we can also use pins or select current values through software.
To support a 48V digital input signal (not a common requirement), a similar process needs to be used, and an external resistor must be added to adjust the voltage threshold at one end of the field. Set the value of this external resistor so that the current limiting value * R+threshold of the pin meets the voltage threshold specification at one end of the field (see device data manual).
Finally, due to the connection between the digital input module and the sensor, the design must meet the requirements of reliable operating characteristics. When using a split type scheme, these protective functions must be carefully designed. When selecting integrated digital input devices, ensure that the following are determined according to industry standards:
Wide input voltage range (e.g. up to 40V).
Able to use on-site power supply (7V to 65V).
Capable of withstanding high ESD (± 15kV ESD air gap) and surges (usually 1KV).
Providing overvoltage and overheating diagnosis is also very useful for MCU to take appropriate actions.
Design a High Channel Density Digital Output Module
A typical discrete digital output design has a FET with a driving circuit driven by a microcontroller. Different methods can be used to configure FETs to drive microcontrollers.
The definition of a high-end load switch is that it is controlled by an external enable signal and connects or disconnects the power supply from a given load. Compared to low-end load switches, high-end switches provide current to the load, while low-end switches connect or disconnect the grounding connection of the load to obtain current from the load. Although they all use a single FET, the problem with low-end switches is that there may be a short circuit between the load and ground. High end switches protect the load and prevent short circuits to ground. However, the implementation cost of low-end switches is lower. Sometimes, the output driver is also configured as a push-pull switch, requiring two MOSFETs. Refer to Figure 4 below.
Integrated DO devices can integrate multiple DO channels into a single device. Due to the different FET configurations used for high-end, low-end, and push-pull switches, different devices can be used to achieve each type of output driver.
Application Scheme of Industrial Ethernet Remote IO Module in Intelligent Manufacturing Workshop
With the advent of Industry 4.0, intelligent manufacturing has become a trend in industrial production. Intelligent manufacturing requires efficient, stable, and reliable industrial Ethernet remote IO modules to monitor the production process. This article will share an application case of an intelligent manufacturing workshop based on industrial Ethernet remote IO module.3721C Invensys Triconex system
The production process of this intelligent manufacturing workshop is mainly divided into two parts: injection molding and automated assembly. The injection molding process requires controlling parameters such as the melting temperature of the melt, the speed and pressure of the injection molding machine. The automated assembly process requires controlling the actions of the assembly robot and detecting the quality of the product. In addition to these production process data, there are also equipment production data such as daily and weekly production in the workshop, as well as equipment status data such as operation, manual, automatic, mold adjustment, and alarm.
In the past, the production process of the factory mainly relied on traditional hard wiring to control the production process, resulting in low work efficiency due to the need for frequent replacement of transmission lines to meet production needs. Moreover, it is very difficult to collect a large number of types of detection and monitoring data for intelligent manufacturing. In order to improve efficiency, production quality, and reliability, the factory has introduced the industrial Ethernet remote IO module MxxT using barium rhenium technology.
The injection molding machine itself comes with MODBUS industrial control bus data or basic status signal output. The barium rhenium technology remote IO module collects data from the device interface RS232/RS485 port, collects status information of the injection molding machine such as startup, operation, and pause, and uploads it to the injection molding machine controller, or wirelessly uploads it to the cloud server. Based on devices, according to the communication protocols and interfaces of different devices, data is obtained by calling their interface channels, and then transmitted to the server.
The remote IO module is connected to the controller of the injection molding machine, and the operation data of the injection molding machine is uploaded and distributed wirelessly, achieving remote monitoring and intelligent control of the injection molding machine. In addition, the remote I/O module supports perceptual access to peripheral devices such as mold temperature machines, cutting machines, and dryers for injection molding machines, providing users with smart factory services.
During the injection molding process, the industrial Ethernet remote IO module transmits real-time data such as temperature, pressure, and speed to the main controller for monitoring and adjustment, ensuring the stability and compliance of production parameters under different conditions. In the automated assembly process, the industrial Ethernet remote IO module collects data through sensors and other devices, and transmits the relevant data to the main controller for adjustment of relevant actions. For example, the industrial Ethernet remote IO module can monitor the actions of assembly robots, detect the accuracy of product assembly and product quality, and ensure the production quality and stability of the product. At the same time, all production data can also be collected and analyzed remotely, helping enterprise managers better monitor production efficiency and quality.
By introducing industrial Ethernet remote IO modules, this intelligent manufacturing workshop not only improves production efficiency and stability, but also reduces labor and energy costs. Because the industrial Ethernet remote IO module can help enterprises complete the collection and monitoring of production data with one click, as well as avoid unnecessary line replacement and the need for workers to enter and exit the production process, thereby reducing costs and improving production efficiency for enterprises.
In summary, the application of industrial Ethernet remote IO modules in intelligent manufacturing workshops not only improves production efficiency and quality, reduces costs, but also achieves intelligent and digital management of production processes, bringing more opportunities and development space for enterprise development.3721C Invensys Triconex system
In addition, this device is widely used for networking and data collection of industrial equipment such as injection molding machines, air compressors, CNC machine tools, on-site PLCs, instruments, sensors, CNC, and electromechanical equipment.
Building a High Channel Density Digital IO Module for the Next Generation Industrial Automation Controller
There are currently many articles introducing Industry 4.0, and smart sensors are becoming increasingly popular in factory environments (I and other authors have written about these topics). Although we have all noticed a significant increase in the use of sensors in factories, processing plants, and even some newly built automation systems, the widespread use of sensors has also brought about an important change, which is the need to handle a large amount of IO within these old controllers. These IOs may be digital or analog. This requires the construction of high-density IO modules with size and heat limitations. In this article, I will focus on digital IO, and in subsequent articles, I will introduce analog IO.
Usually, digital IO in PLC consists of discrete devices such as resistors/capacitors or independent FET drives. In order to minimize the size of the controller as much as possible and to handle 2 to 4 times the number of channels, this has led to a shift from a separate approach to an integrated approach.
We can use the entire article to illustrate the drawbacks of the split method, especially when the number of channels processed by each module reaches 8 or more. However, when it comes to high heat/power consumption, a large number of split components (from the perspective of size and mean time between failures (MTBF)), and the need for reliable system specifications, it is sufficient to demonstrate that the split method is not feasible.
Figure 1 shows the technical challenges faced in building high-density digital input (DI) and digital output (DO) modules. In both Di and DO systems, size and heat dissipation issues need to be considered.
Digital input
size
heat
Supports all input types
Type 1, 2, 3, Input
Supports 24 V and 48 V inputs
Robust operating specifications
Wire breakage detection
Digital output
Support for different types of output driver configurations
size
Integrated demagnetization of inductive loads
Heat – When driving multiple outputs
Drive accuracy
diagnosis
For digital input, it is also important to note that it supports different input types, including 1/2/3 type inputs, and in some cases, 24V and 48V inputs. In all cases, reliable operating characteristics are crucial, and sometimes circuit detection is also crucial.
For digital outputs, the system uses different FET configurations to drive the load. The accuracy of the driving current is usually an important consideration. In many cases, diagnosis is also very important.
We will explore how integrated solutions can help address some of these challenges.
Design a High Channel Density Digital Input Module
The traditional split design uses a resistive voltage divider network to convert 24V/48V signals into signals that can be used by microcontrollers. The front-end can also use discrete RC filters. If isolation is required, external optocouplers are sometimes used.
Figure 1 shows a typical discrete method for constructing digital input circuits.
Figure 1. Considerations for digital input and output modules.
This type of design is suitable for a certain number of digital inputs; 4 to 8 per board. Beyond this number, this design will soon become impractical. This separation scheme can bring various problems, including:
High power consumption and related board high temperature points.
Each channel requires an optocoupler.
Excessive components can lead to low FIT rate and even require larger devices.
More importantly, the split design method means that the input current increases linearly with the input voltage. Assuming a 2.2K Ω input resistor and 24V V is used. When the input is 1, for example, at 24V, the input current is 11mA, which is equivalent to a power consumption of 264mW. The power consumption of the 8-channel module is greater than 2W, and the power consumption of the 32-bit module is greater than 8W. Refer to Figure 3 below
From a cooling perspective alone, this split design cannot support multiple channels on a single board.
One of the biggest advantages of integrated digital input design is the significant reduction in power consumption, thereby reducing heat dissipation. Most integrated digital input devices allow configurable input current limitations to significantly reduce power consumption.
When the current limiting value is set to 2.6mA, the power consumption is significantly reduced, with each channel approximately 60mW. The rated value of the 8-channel digital input module can now be set below 0.5
Another reason for opposing the use of split logic design is that sometimes DI modules must support different types of inputs. The standard 24V digital input specifications published by IEC are divided into Type 1, Type 2, and Type 3. Type 1 and Type 3 are usually used in combination because their current and threshold limits are very similar. Type 2 has a current limit of 6mA, which is higher. When using the split method, it may be necessary to redesign as most discrete values need to be updated.
However, integrated digital input products typically support all three types. Essentially, Type 1 and Type 3 are generally supported by integrated digital input devices. However, in order to meet the minimum current requirement of 6mA for Type 2 input, we need to use two channels in parallel for one field input. And only adjust the current limiting resistance. This requires a circuit board change, but the change is minimal.
For example, the current maximum integrated (now part of ADI company) DI device has a current limiting value of 3.5mA/channel. So, as shown in the figure, we use two channels in parallel. If the system must be connected to a Type 2 input, adjust the REFDI resistance and RIN resistance. For some newer components, we can also use pins or select current values through software.
To support a 48V digital input signal (not a common requirement), a similar process needs to be used, and an external resistor must be added to adjust the voltage threshold at one end of the field. Set the value of this external resistor so that the current limiting value * R+threshold of the pin meets the voltage threshold specification at one end of the field (see device data manual).
Finally, due to the connection between the digital input module and the sensor, the design must meet the requirements of reliable operating characteristics. When using a split type scheme, these protective functions must be carefully designed. When selecting integrated digital input devices, ensure that the following are determined according to industry standards:
Wide input voltage range (e.g. up to 40V).
Able to use on-site power supply (7V to 65V).
Capable of withstanding high ESD (± 15kV ESD air gap) and surges (usually 1KV).
Providing overvoltage and overheating diagnosis is also very useful for MCU to take appropriate actions.
Design a High Channel Density Digital Output Module
A typical discrete digital output design has a FET with a driving circuit driven by a microcontroller. Different methods can be used to configure FETs to drive microcontrollers.
The definition of a high-end load switch is that it is controlled by an external enable signal and connects or disconnects the power supply from a given load. Compared to low-end load switches, high-end switches provide current to the load, while low-end switches connect or disconnect the grounding connection of the load to obtain current from the load. Although they all use a single FET, the problem with low-end switches is that there may be a short circuit between the load and ground. High end switches protect the load and prevent short circuits to ground. However, the implementation cost of low-end switches is lower. Sometimes, the output driver is also configured as a push-pull switch, requiring two MOSFETs. Refer to Figure 6 below:
Integrated DO devices can integrate multiple DO channels into a single device. Due to the different FET configurations used for high-end, low-end, and push-pull switches, different devices can be used to achieve each type of output driver.
Estimated power consumption of digital input modules constructed using split logic.
Internal demagnetization of inductive loads
One of the key advantages of integrated digital output devices is their built-in inductive load demagnetization function.
Inductive load is any device containing a coil that, after being energized, typically performs some mechanical work, such as solenoid valves, motors, and actuators. The magnetic field caused by current can move the switch contacts in relays or contactors to operate solenoid valves or rotate the motor shaft. In most cases, engineers use high-end switches to control inductive loads, and the challenge is how to discharge the inductance when the switch is turned on and the current no longer flows into the load. The negative effects caused by improper discharge include: possible arcing of relay contacts, significant negative voltage spikes that damage sensitive ICs, and the generation of high-frequency noise or EMI, which can affect system performance.
The most common solution for discharging inductive loads in a split type scheme is to use a freewheeling diode. In this circuit, when the switch is closed, the diode is reverse biased and non-conductive. When the switch is turned on, the negative supply voltage through the inductor will cause the diode to bias forward, thereby attenuating the stored energy by guiding the current through the diode until it reaches a stable state and the current is zero.
For many applications, especially in the industrial industry where each IO card has multiple output channels, the diode is usually of large size, which can lead to a significant increase in cost and design size.
Modern digital output devices use an active clamping circuit to achieve this function within the device. For example, Maxim Integrated adopts a patented SafeDemag ™) Function, allowing digital output devices to safely turn off loads without being limited by inductance.
When selecting digital output devices, multiple important factors need to be considered. The following specifications in the data manual should be carefully considered:
Check the maximum continuous current rating and ensure that multiple outputs can be connected in parallel when needed to obtain higher current drivers.
Ensure that the output device can drive multiple high current channels (beyond the temperature range). Refer to the data manual to ensure that the conduction resistance, power supply current, and thermoelectric resistance values are as low as possible.
The output current driving accuracy specifications are also important.
Estimated power savings for digital input modules using integrated DI chips.
Diagnostic information is crucial for recovering from operating conditions that exceed the range. Firstly, you want to obtain diagnostic information for each output channel. This includes temperature, overcurrent, open circuit, and short circuit. From an overall (chip) perspective, important diagnoses include thermal shutdown, VDD undervoltage, and SPI diagnosis. Search for some or all of these diagnoses in integrated digital output devices.
Programmable digital input/output device
By integrating DI and DO on the IC, configurable products can be built. This is an example of a 4-channel product that can be configured as input or output.
It has a DIO core, which means that a single channel can be configured as DI (Type 1/3 or Type 2) or digital output in high-end or push-pull mode. The current limiting value on DO can be set to 130mA to 1.2A. Built in demagnetization function. To switch between type 1/3 or type 2 digital inputs, we only need to set one pin without using an external resistor.
These devices are not only easy to configure, but also sturdy and durable, and can work in industrial environments. This means high ESD, providing up to 60V power supply voltage protection and line grounding surge protection.
This is an example of a potentially completely different product (configurable DI/DO module) that can be implemented through an integrated approach.
conclusion
When designing high-density digital input or output modules, it is evident that when the channel density exceeds a certain number, the split scheme is meaningless. From the perspectives of heat dissipation, reliability, and size, it is necessary to carefully consider integrated device options. When selecting integrated DI or DO devices, it is important to pay attention to some important data points, including reliable operating characteristics, diagnosis, and support for multiple input-output configurations.
1.Has been engaged in industrial control industry for a long time, with a large number of inventories.
2.Industry leading, price advantage, quality assurance
3.Diversified models and products, and all kinds of rare and discontinued products
4.15 days free replacement for quality problems
ABB — AC 800M controller, Bailey, PM866 controller, IGCT silicon controlled 5SHY 3BHB01 3BHE00 3HNA00 DSQC series
BENTLY — 3500 system/proximitor, front and rear card, sensor, probe, cable 3500/20 3500/61 3500/05-01-02-00-001 3500/40M 176449-01 3500/22M 138607-01
Emerson — modbus card, power panel, controller, power supply, base, power module, switch 1C31,5X00, CE400, A6500-UM, SE3008,1B300,1X00,
EPRO — PR6423 PR6424 PR6425 PR6426 PR9376 PR9268 Data acquisition module, probe, speed sensor, vibration sensor
FOXBORO — FCP270 FCP280 FCM10EF FBM207 P0914TD CP40B FBI10E FBM02 FBM202 FBM207B P0400HE Thermal resistance input/output module, power module, communication module, cable, controller, switch
GE —- IS200/215/220/230/420 DS200/215 IC693/695/697/698 VMICPCI VMIVME 369-HI-R-M-0-0-E 469 module, air switch, I/O module, display, CPU module, power module, converter, CPU board, Ethernet module, integrated protection device, power module, gas turbine card
HIMA — F3 AIO 8/4 01 F3231 F8627X Z7116 F8621A 984862160 F3236 F6217 F7553 DI module, processor module, AI card, pulse encoder
Honeywell — Secure digital output card, program module, analog input card, CPU module, FIM card
MOOG — D136-001-007 Servo valve, controller, module
NI — SCXI-1100 PCI – PXIE – PCIE – SBRIO – CFP-AO-210 USB-6525 Information Acquisition Card, PXI Module, Card
Westinghouse — RTD thermal resistance input module, AI/AO/DI/DO module, power module, control module, base module
Woodward — 9907-164 5466-258 8200-1300 9907-149 9907-838 EASYGEN-3500-5/P2 8440-2145 Regulator, module, controller, governor
YOKOGAWA – Servo module, control cabinet node unit
Main products:
PLC, DCS, CPU module, communication module, input/output module (AI/AO/DI/DO), power module, silicon controlled module, terminal module, PXI module, servo drive, servo motor, industrial display screen, industrial keyboard, controller, encoder, regulator, sensor, I/O board, counting board, optical fiber interface board, acquisition card, gas turbine card, FIM card and other automatic spare parts
