اچ ام ای delta

HMI stands for Human Machine Interface. This means that a person connected to the system via HMI can command or read the information they need. Let me give you an example: we have a device that we want to increase or decrease its production speed or we know the temperature of a point. Naturally, we can not see the temperature through PLC and we need a device to monitor it. It is an HMI device. In fact, the USER or operator through the HMI can command the system, for example, to determine how many cans are produced per hour and also to monitor the information that is needed, such as temperature, pressure, speed and… by monitoring the information if there is a problem with the system The operator understands and can act accordingly. So in general HMI is a graphics panel that is the interface between human and machine. In fact, humans can communicate with the system through this. It also has a very wide range. Your phone screen is also an دلتا hmi . It is through this panel that you control the phone and its program.

How is HMI used in the control system ??

Before HMI was built, a control system could have thousands of PUSH-BUTTON keys. But in HMI, put these keys very stylishly in places so that the operator can use them easily. This application of HMI in the control system is called pushbutton replacer.

Another is to use HMI via data handler. You can analyze the data by monitoring it on the HMI or, for example, plotting a graph, plotting, and analyzing this data to fix the flaws of your system.

How does HMI communicate with control system components?

Because we are dealing with an industrial system, industrial networks are involved. Many manufacturers in the world make HMIs such as Siemens, Ellen Bradley, ABB, Delta and M

In the world of automation, a series of standards have been set so that parts of different companies can communicate with each other. One of these is industrial networks.

Each HMI has a number of ports such as RS232, RS422, RS485, newer HMIs also have an Ethernet port (ETHERNET) through which these ports can connect to other components such as PLC, inverter, sensors and..

Where is the HMI in a control system?

The following figure shows a block diagram that shows the general usage of HMI in a control system.

 

As you can see, the HMI connects to the PLC and takes a series of information from the PLC and monitors it, and also sends a series of data to the PLC, such as the SET POINTS that the operator wants to apply to the system. This is a general case of using HMI. In an HMI control system, it is possible to connect directly to the inverter and command directly to the inverter, but the general mode of using HMI is as shown above.

How to choose the right HMI for the control system ??

Well, the question of many dear engineers is how to choose the right HMI for our work. Each brand has a large number of HMIs, each of which must be used in its place, and a good engineer must be able to make the best choice for his project.

1- Price: As you know, in every industrial project, economy plays the first role. So it is not that you can choose a HMI with the best quality and Full Port in every project.

2- Communication ports: You should check which network your control system can support. For example, it supports RS485. So you no longer need to buy Ethernet HMI because it is more expensive than other models.

3- HMI size: We said above that one of the uses of HMI is pushbutton replacer mode. You should see how many switches, switches and… you want to place on the HMI screen and select the appropriate size. Or if you want to analyze the data, see if HMI has the ability to draw graphs.

4- Environmental conditions: You should choose according to the conditions in which the HMI is to be placed. For example, there is a lot of noise and vibration in a device, you should choose a heavy-duty HMI. Choose waterproof HMI in food industry processes. In fact, it should have a higher IP. Or there may be a high temperature in your environment to which the HMI should be chosen.

HMI types:

There are generally two types of HMIs:

1- TOUCH PANEL

2- TEXT PANEL

Well, text panels give you fewer tools and, of course, are cheaper.

 

In what industries is HMI used?

HMI is widely used in various industries. Industries such as:

Food and beverage industry

Pharmacology

production lines

Machine building such as plastic injection machine

      And….

It should be noted that in large industries such as power plants, steel and… PC base systems are used.