Description
3201 Safety Instrumented System (SIS)
3201 Safety Instrumented System (SIS)
Module Clips Drive controller servo motor
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What is the function of an IO chip
Io generally refers to input and output devices, where I is the input and O is the output. The input to the IO port of the chip is the external signal transmission to the chip, while the output is the internal signal transmission to other devices. The input and output are relative. In short, in a broad sense, the control of input and output interfaces is called an IO chip, and network cards are also considered IO or array cards.
The CPU must read and write data to external registers or ROMs on RAM or other hardware through IO commands (such as input/output commands). For example, reading a keyboard involves accessing external registers on the keyboard through the 60H port, and the chip on the keyboard scans the keyboard. Pressing or holding down a key for a long time will cause the chip to generate corresponding scan or break codes, which will be written to the external register of the 60H port, so that the CPU can achieve the purpose of controlling the keyboard. Therefore, I think IO chips should refer to a large category. The CPU already has powerful IO instructions and corresponding control buses.
51 microcontroller IO port input and output mode_ Four usage methods for IO ports
The traditional 51 microcontroller IO interface can only be used as a standard bidirectional IO interface. If it is used to drive LED, it can only be driven by injecting current or using a transistor external expansion drive circuit.
Current injection method: LED positive pole connected to VCC, negative pole connected to IO port. If the IO is at a high level, the two poles of the LED are at the same level, and there is no current, the LED will turn off; IO is at low power level, current flows from VCC to IO, and LED lights up. But when you connect the positive pole of the LED to the IO interface and the negative pole to GND, placing the IO interface at a high level will cause the LED to light up. However, due to the insufficient pull-up capability of the IO interface, the brightness is not ideal. The following method can be used to solve this problem.
Push-pull working mode: The positive and negative poles of the LED are connected to two IO ports, and then the positive IO interface is set as the push-pull output, while the negative IO interface is set as the standard bidirectional current input. The push pull method has strong pull-up ability and can achieve high-level LED driving.
Four usage methods for IO ports3201 Safety Instrumented System (SIS)
From the perspective of the characteristics of the I/O port, the P0 port of Standard 51 is an open drain structure when used as an I/O port, and in practical applications, a pull-up resistor is usually added; P1, P2, and P3 are all quasi bidirectional I/Os with internal pull-up resistors, which can be used as both input and output. The I/O port characteristics of the LPC900 series microcontroller have certain differences, and they can be configured into four different working modes: quasi bidirectional I/O, push pull output, high resistance input, and open drain.
Compared with Standard 51, the quasi bidirectional I/O mode differs in internal structure but is similar in usage. For example, when used as an input, it must first write “1” to set it to high level before reading the level state of the pin.!!!!! Why is it like this? Please refer to the diagram below for analysis.
The characteristic of push-3201 Safety Instrumented System (SIS)pull output is that it can drive a large current regardless of whether it outputs high or low levels. For example, when outputting high levels, it can directly light up the LED (by connecting several hundred ohm current limiting resistors in series), which is difficult to achieve in quasi bidirectional I/O mode.
The characteristic of high impedance input mode is that it can only be used as an input, but it can obtain relatively high input impedance, which is necessary in analog comparator and ADC applications.
The open drain mode is similar to the quasi bidirectional mode, but there is no internal pull-up resistance. The advantage of open drain mode is good electrical compatibility. If the external pull-up resistor is connected to a 3V power supply, it can interface with a 3V logic device. If the pull-up resistor is connected to a 5V power supply, it can also interface with a 5V logic device. In addition, the open drain mode can also conveniently implement the “line and” logic function.
For the explanation of the above question, there is this information:
High resistance state is a common term in digital circuits, referring to an output state of a circuit that is neither high nor low. If the high resistance state is input into the next level circuit, it has no impact on the lower level circuit, just like not connected. If measured with a multimeter, it may be high or low, depending on what is connected afterwards.
High resistance states can be understood as open circuits during circuit analysis. You can think of it as having a very high output (input) resistance. His limit can be considered suspended.
Typical applications of high resistance states:
1. On the bus connected structure. There are multiple devices hanging on the bus, and the devices are connected to the bus in a high impedance form. This automatically releases the bus when the device does not occupy it, making it easier for other devices to gain access to the bus.
2. Most microcontroller I/O can be set to high impedance input when used, such as Lingyang, AVR, and so on. High resistance input can be considered as having infinite input resistance, indicating that I/O has minimal impact on the preceding stage and does not generate current (without attenuation), and to some extent, it also increases the chip”s resistance to voltage surges.
MQTT IoT Remote IO Module Based on Ethernet Communication Technology
MQTT IoT Remote IO Module Based on Ethernet Communication Technology
Barium rhenium technology remote IO modules are widely used in IoT scenarios such as intelligent transportation, smart water conservancy, smart agriculture, smart campuses, smart communities, smart power distribution, and smart water conservancy.
With the development of IIOT industrial Internet of Things technology, more and more traditional assets need to be connected to the internet, achieving unified data collection and analysis, and breaking the phenomenon of traditional device information silos. The barium rhenium technology remote IO module M160T, which supports IoT protocols, has become an excellent choice for many enterprises to achieve device networking, remote control, and data collection based on the compatibility of existing devices and the accessibility of IoT platforms!
Ethernet communication technology is a mature communication technology because it has the characteristics of stability, reliability, mature technology, fast transmission speed, and fast construction wiring. Due to its wide application, Ethernet communication through the MQTT protocol is the main way for enterprise equipment to go to the cloud. Barium rhenium technology can quickly collect data and control such as air compressor room, property living pump room, street light control, liquid level collection, temperature and humidity collection through Ethernet remote IO module.3201 Safety Instrumented System (SIS)
So, why is the remote IO module of barium rhenium technology widely used in the field of industrial IoT? The specific reasons are as follows.
1. Actively connect to cloud platforms:
Based on the characteristics of Ethernet communication networks, the barium rhenium technology remote IO module does not require complex settings such as peanut shells to achieve the Internet of Things. The barium rhenium technology remote IO module needs to support both TCP client and TCP server functions.
2. Compatibility with existing systems:
It supports TCP Server and Modbus TCP protocol functions, and is compatible with device access of traditional upper level systems or HMI TCP clients.
3. Support multiple IoT platforms:
Supports standard MQTT, Modbus TCP, and Modbus RTU over TCP protocols. It can be connected to public cloud IoT platforms and user built MQTT private clouds through the MQTT protocol. It can also be connected to SCADA and DCS systems through Modbus TCP.
4. Rich IO interfaces and scalability:
There are many types of IO for industrial field data collection and replication. The Ethernet IO module of barium rhenium technology supports signal acquisition from various devices such as 4-20Ma, 0-20mA, 0-5V, 0-10V, RS485, DI, DO, PT100, PT1000, pulse input, pulse output, etc. At the same time, it expands the instrument data reading ability of RS485 devices.
5. Convenient installation method:
The volume of industrial on-site control boxes is often very limited, and the barium rhenium technology Ethernet IO module adopts a direct plug-in connection terminal and rail installation method. The compact volume greatly saves space in the control box!
6. Industrial grade design
The industrial environment is harsh, and the remote IO module using barium rhenium technology needs to adopt an industrial grade design, which can work continuously and stably in harsh environments.
Through the use of barium rhenium technology remote IO modules, there is no need to replace existing various enterprise assets, and the digital transition to the Internet of Things platform can be quickly achieved. Therefore, barium rhenium technology remote IO modules are widely used in industrial IoT, such as intelligent real estate, intelligent campus, intelligent factory, intelligent transportation, intelligent water conservancy, intelligent agriculture, intelligent campus, intelligent community, intelligent transportation, and many other industries.
What is the role of distributed IO modules and what are their main applications in
The distributed IO module transmits status signals from the measurement and control field to various measurement and control fields for control. It is mainly used in the industrial field and can also be used for detection of equipment such as air conditioners and motors.
In distributed systems, there are important business data closely related to system operation, as well as data related to nodes, application services, and data services, which are crucial for the normal operation of clusters.
IO on general PLCs is usually closely followed by CPU units, but in order to facilitate connection and maintenance, the concept of distributed IO has been proposed in the industrial field. That is to say, the IO unit can be arranged far away from the PLC CPU unit and communicate through the network communication protocol of the device layer.
The distributed IO module is developed for detecting and implementing remote control of various types of standard analog and switch signals (frequency, pulse, or switch state signals) in the field of measurement and control. The series of modules can digitize the test signal front-end and transmit it to the host through optical fiber; Or transmit the control instructions sent by the host to the controlled device to achieve remote control. Especially suitable for state detection and control of complex electromagnetic environments in power, industrial control, on-site switchgear, and large power equipment.
The role of distributed IO modules:
1. Support 4-way switch digital quantity
2. Supports 8 analog inputs
3. 4 relay outputs, 1 RS485 serial port data acquisition to Ethernet
4. 485 to Ethernet serial server
5. Supports Modbus to TCP/UDP protocol conversion
6. Supports virtual serial ports and interfaces with various configuration software
7. Support 0-5V, 0-10V, 0-30V range acquisition
8. Supports 0-20ma and 4-20ma range acquisition
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 Collection3201 Safety Instrumented System (SIS)
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.3201 Safety Instrumented System (SIS)
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 are the characteristics of a demonstration system based on IO Link slave stations
IO Link is an industrial communication interface that is independent of any fieldbus and suitable for simple sensors and actuators at the lowest level of industrial control. The IO Link system includes IO Link devices (such as sensors and actuators), IO Link master stations, and cables for standard sensors. The system structure is shown in Figure 1. For example, when a remote IO module compatible with EtherNet/IP serves as the master station, in addition to standard I/O signals, the module sends and receives configuration data, diagnostic data, or enhanced process data through a pulse modulation process, which is then packaged into EtherNet/IP data packets and finally transmitted to the network master station, usually a PLC. In the above applications, the connection between remote I/O and IO Link devices remains the same as that of traditional discrete devices. The advantage of IO Link mainly lies in its greater information exchange capability, which was previously impossible to achieve with standard I/O devices. Another advantage of IO Link is that it does not rely on any fieldbus, and through any I/O module that complies with the IO Link protocol (including local I/O and remote I/O), IO Link sensors or actuators can be integrated into any fieldbus system.
In order to further study the architecture, communication mechanism, and development application of the IO Link system, an IO Link slave toolkit can be designed and developed, including a universal development module for IO Link, an IO Link analysis tool, and an IO Link slave protocol stack. The IO Link universal development module is the foundation for this work and also serves as a bridge between the IO Link master station and equipment signals. The IO Link analysis tool can help developers and testers analyze communication details to identify and solve problems. The IO Link slave protocol stack is a firmware library that provides a hardware abstraction layer and application program interface, allowing developers to easily and quickly develop IO Link slave products on various microprocessor platforms. The IO Link slave station studied in this article only focuses on digital (button) signal input and digital signal output (indicator light). The design of the IO Link universal development module only needs to be expanded on this basis to have the ability to process analog signals.
The IO Link Master module used in this article, USB IO Link Master, can connect IO Link devices to a PC, which can be configured and tested through the IO Link Device Tool software or demonstrated device functionality. IO Link devices must be described through a device description file (IODD file), which includes a set of XML text files and PNG graphic files, which contain information about device identification, communication characteristics, parameters, process data, and diagnostic data. The portion within the elliptical dashed line in Figure 2 is an IO Link three wire cable, with L+/I – being a 24 V DC power supply and C/Q being a signal line used to transmit process data, diagnostic data, configuration data, etc. The IO Link universal development module is mainly composed of data transceivers and microprocessors. It can process input signals from sensors and transmit information to the IO Link master station. It can also receive and process data information from the master station and transmit it to the actuator. The IO Link analysis tool can help developers view, record, analyze data, and understand communication details. This part of the design is not discussed in this article.
Introduction to IO Link Communication Mode3201 Safety Instrumented System (SIS)
IO Link devices can operate in SIO mode (standard I/O mode) or IO Link mode (communication mode). After power on, the device always operates in SIO mode. The port of the main station has different configuration methods. If configured in SIO mode, the main station considers the port as a standard digital input. If configured in communication mode, the main station will automatically identify the communicable devices for communication.
2.1 Data Types3201 Safety Instrumented System (SIS)
The three basic data types for IO Link communication are periodic data (or process data PD), non periodic data (or service data SD), and event.
The process data (PD) of the device is transmitted periodically in the form of a data frame, while service data (SD) is only exchanged after the master station issues a request. Figure 3 shows a typical IO Link message structure. When an event occurs, the “event flag” of the device is set, and the main station reads the reported event (service data cannot be exchanged during the reading process) upon detecting the setting. Therefore, events such as pollution, overheating, short circuits, or device status can be transmitted to the PLC or visualization software through the main station
2.2 Parameter data exchange
Since service data (SD) must be transmitted through PLC requests, SPDU (Service Protocol Data Unit) is defined. In the main station, requests for read and write services are written to SPDU and transmitted to devices through the IO Link interface.
The general structure of SPDU is shown in Figure 4, and its arrangement order is consistent with the transmission order. The elements in SPDU can take different forms depending on the type of service. SPDU allows access to data objects that are intended for transmission, while Index is used to specify the address of the requested data object on the remote IO Link device. In IO Link, there is a term called direct parameter page, which stores parameter information such as minimum cycle time, supplier ID, and master station commands. The data objects accessible in the direct parameter page can be selectively provided through SPDU.
HMT7742 is an IO Link slave transceiver chip that serves as a bridge between the MCU of external sensors or actuators and the 24V signal line that supports IO Link communication. When the IO Link device is connected to the master station, the master station initializes communication and exchanges data with the MCU. HMT7742 serves as the physical layer for communication.
Due to the fact that the three indicator lights (rated voltage 24 V) controlled by the output port of the MCU are powered by the IO Link power cord, it is necessary to monitor the current on the power cord in order to trigger appropriate corrective measures when the current exceeds a set threshold, such as removing the indicator lights from the IO Link power cord. The current monitoring module uses an INA194 current detection amplifier. As a high detection current detector, INA194 is directly connected to the power supply and can detect all downstream faults. It has a very high common mode rejection ratio, as well as a large bandwidth and response speed. It can amplify the voltage on the induction resistor 5O times and output it to the forward input terminal AIN0 of the MCU internal voltage comparator. When the voltage value of AIN0 exceeds the threshold set at the reverse input terminal, By controlling the low level output of PB0, the indicator LAMP can be cut off from the IO Link power line to achieve overcurrent protection function. This part of the circuit is shown in Figure 6.
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.3201 Safety Instrumented System (SIS)
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-3201 Safety Instrumented System (SIS)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.
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.
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
