What is the difference between HMI and touch screen?

1. What is the difference between the human-machine interface and the "touch screen" that people often say?

Strictly speaking, there are essential differences between the two. Because the "touch screen" is only the hardware part that may be used in the human-machine interface product, it is the input device installed in front of the display screen, not the mouse and keyboard. A human-machine interface product is a human-computer interaction device, including hardware and software. In the industry, people often refer to the products with touch input function of human-machine interface as "touch screen", but this is unscientific.

2. What is the difference between man-machine interface and configuration software?

Human-machine interface products, commonly referred to as "touch screens", include HMI hardware and corresponding special screen configuration software. Generally, HMI hardware of different manufacturers uses different screen configuration software, and the type of connected equipment is mainly PLC. Configuration software is a general tool software product running on PC hardware platform and windows operating system, and can also be combined with PC or industrial computer to form HMI products. The general configuration software supports a variety of equipment, such as various PLCs, PC boards, instruments, frequency converters, modules and other equipment. And because of the powerful performance of the PC hardware platform (mainly reflected in the speed and storage capacity), the general configuration software has many stronger functions and is suitable for large-scale monitoring systems.

3. Is there an operating system in the HMI product?

Any HMI product has a system software part. The system software runs on the processor of the man-machine interface and supports multitasking. The processor requires a small operating system management system software to run. Tablet PC-based high-performance human-machine interface products generally use common embedded operating systems such as WinCE and Linux.

4. Can the HMI only be connected to PLC? Touch Industrial Panel PC Products1

that is not real. Human-machine interface products are produced to solve the human-computer interaction problem of PLC, but with the development of computer technology and digital circuit technology, many industrial control devices have serial communication capabilities, so as long as the industrial control equipment with serial communication capabilities Control equipment, such as frequency converter, DC governor, temperature control instrument, data acquisition module, etc., can be connected with the product of the human-machine interface to realize the function of human-computer interaction.

5. Can the man-machine interface only be connected to other devices through the standard serial communication port?

In most cases, it is. But with the development of computer and digital circuit technology, the interface capability of human-machine interface products is getting stronger and stronger. In addition to the traditional serial (RS232, RS422/RS485) communication interfaces, some human-machine interface products already have data interfaces such as network ports, parallel ports, and USB ports. They can be connected with industrial control equipment through interfaces such as network ports, parallel ports, and USB ports, to realize the human-computer interaction of the device.

6. Are communication-capable devices always connected to HMI products?

It should be like this. Because the universal human-machine interface product provides a large number of commonly used device communication drivers to choose from; under normal circumstances, as long as the communication driver corresponding to the connected device is selected in the screen configuration software of the human-machine interface, the HMI and the device can be completed. communication connection. If the configuration software of the selected HMI product does not contain the communication driver of the device to be connected, the user can inform the manufacturer of the HMI product of the communication port type and protocol content of the device to be connected, and ask the HMI manufacturer to compile the communication driver for the device .

7. With a PC and a touch screen, can you directly communicate with the PLC to complete the HMI function?

of course can. However, only by writing the corresponding HMI software, the PC can become a real HMI product.

8. What is the future development trend of human-machine interface?

With the development of digital circuits and computer technology, the functional division of human-machine interface products will become less and less obvious in the future, and the functions of HMI will become more and more abundant. HMI products larger than 5.7 inches will all be color displays, with longer screen life. Due to the reduction in the cost of computer hardware, HMI products will mainly use tablet computers as high-end products of HMI hardware, because such high-end products are in terms of processor speed, storage capacity, type and number of communication interfaces, networking capabilities, software resource sharing, etc. Both have great advantages and will be the development direction of HMI products in the future. Of course, HMI products with small size (display size less than 5.7 inches) will be widely used in the human-computer interaction of small mechanical devices with the further enhancement of their functions (such as adding IO functions) due to their advantages in size and price in application.