Tag Archives: Learn PLC programming

what basic knowledge to learn plc?

Need to have an electrician, assemble secondary lines, and understand the basics of various relays.

Learning the PLC can be done as follows:

1. Buy this book about PLC, learn about electrician knowledge, understand the electrical appliances, and go to control and understand various actuators.

2, is to understand the working mode of PLC, find a PLC, according to the example on the book, consider a small project, to achieve a function.

3, practice the true knowledge, understand the corresponding process, do a PLC project independently, the project is completed, the PLC will also master the Siemens 200 series of small PLC is very suitable for novice learning, easier to get started.

What is the foundation for learning plc programming?

The conditions for self-learning PLCs should be as follows:
1, you have to learn programming software PLC (such as Siemens, Delta, Omron, etc.), each brand of PLC its programming software is slightly different, so what software to prepare what PLC.
2, it is best to reserve an HMI (Human Machine Interface), because PLC often needs to do some configuration control, it is really not good to achieve this, of course, now a lot of two in one, you can prepare a two-in-one device it is good.
3, a set of PLC programming software and HMI programming software
4. Relevant circuit design knowledge.

how to connect plc to hmi

How to connect plc to hmi

I want to modify the timer’s time with the touch screen.
1. Read out the program in FX2N PLC with software, find the constant value K of the timer used to set the time, modify the constant K to D directly when programming, D should choose power off to keep the data register, the range is between D200-D511, and other fixed, and then write it into PLC.
2. Choose the type of touch screen, it is recommended to choose the Vinylon MT6056iv touch screen, programming with software, a numeric setting button, the button corresponding to the PLC data register D, when the finger touches the button, there will be numeric input keyboard, at this time, you can modify the timer time.
In the market, any touch screen and PLC usually do not communicate well. There are four problems to be confirmed.
1, is the PLC parameter consistent with that in the project?
2, whether the communication line is connected to the pin according to the wiring diagram.
3, the project set up the COM port on the screen when the correct 4. Parameters and line confirmation OK, in the case of PLC program or PLC address problem.

Methods: (first judge parameters:)

1. Use the programming software of PLC to connect with the PLC test to see what the parameters of PLC are and whether the parameters set in the project are consistent with the test results.
2. On-line simulation: with our configuration software, using the plc’s own communication cable and computer connection, on-line simulation to see if the project is communicating. You can use a numeric input unit or switch to operate on it, to see if the simulator is turned off and then on-line simulation before the operation is still, whether direct prompt NC. (NC and previous operations have not been written down.
(test line): use the multimeter to define the test wiring according to the pin of the wiring diagram.
A: parameters of touch screen. Check the parameter settings of the touch screen.
There are several parameters that need special attention.
1: Communication Port Settings – – – – – – – – – – Make sure that the PLC connects to the touch screen COM1 port or COM2 port
2: Type of equipment – – – – – – – – – – – – – – – – – – – – – – This is the most important, if the agreement is not chosen correctly, the others do not have to say
3: Connection mode – ————– PLC and touch screen connection, confirm good news RS485, or RS232C
4: Interface parameters and PLC station number – ———– must be consistent with the PLC settings.
B: if the parameter confirmation is set up, then check the wiring problem. Confirm the correctness of RS485 and RS232C, and touch screen is different from all kinds of PLC wiring. This can refer to dimensional control (PLC and touch screen communication line help files).
This is the basic method of normal troubleshooting communication problems.
Next we will teach you how to bypass the problem of touch screen — online simulation.
When communication fails, some customers guess that it may be a touch screen problem or an interface problem.
Online simulation is to bypass the touch screen and connect directly to the computer with PLC.

Specific measures:

1:PLC is connected to the computer through RS232. Some PLC have RS232 interface, some do not, and none can connect to the computer through the adapter.
2: build a simple project. Put two components, a numeric value, a numeric input. Address to set the address in PLC.
3: the setting of engineering parameters must be the same as that in PLC.
4: click on the online simulation function, so you can clearly check whether PLC can communicate with PC. If you can communicate, you can exclude the problems of PLC, and the problem of parameter setting.

How to use plc control the DC motor

PLC control DC motor: PLC output control relay, relay control contact DC contactor.


1, MPS (into the stack instruction): The result of the operation into the first segment of the stack memory, while the previously sent data to move to the next section of the stack.

2, MRD (read stack instruction): the first paragraph of the stack memory data (last into the stack of data) read and the data continues to be stored in the first paragraph of the stack, the data in the stack does not move.

3, MPP (out of the stack instruction): The stack memory of the first piece of data (the last stack of data) read and the data from the stack disappeared, while the other data in the stack in turn up.

What does the INCP in Mitsubishi PLC mean?

INCP only to register +1, before adding a condition, connect +1.
such as INCP D100, even if D100 internal data +1
It’s only a connection

What‘s’ mean of Mitsubishi PLC directive MOVP HOFF k2y0

The MOVP represents the pulse transmission instruction,The h in Hoff represents the 16 binary, which represents the hexadecimal FF,K2y0 represents Y7y6y5y4y3y2y1y0, which is the two sets of 4 digits starting with Y0, and if K1y0 represents Y3y2y1y0,This directive indicates that the 16-in-system FF is delivered to the results of the y7y6y5y4y3y2y1y0 execution y7=1, y6=1, Y5=1, Y4=1, Y3=1, Y2=1, Y1=1, Y0=1.

What is the meaning of MOVP in PLC?

The MOV in PLC is the transmission instruction, for example [mov K15 D100] means to transfer the decimal constant K15 to register D100.

MOV is continuous execution, that is, each scan cycle is transmitted once.



MOV K100 D10

When X0 is ON, K100 is transmitted to D10 and automatically converted to binary number.

MOVP is a pulse execution, that is, the instruction is activated once, and a transfer is performed.

MOVP K2M200 D40

The value of m200–m207 in decimal form is assigned to D40
MOVP K11 D0:

A transfer process is performed when conditions are available.

(pass constant 11 to D0 data register). It is usually performed only when there is a rising edge.


It is to transmit H1A1 to module 0, buffer 0.

Application of PLC in capsule curing machine

In the tire curing process, the capsule as the necessary parts of the tire processing, there is a high performance requirements. It needs to undergo repeated expansion and contraction, stretching and other deformation, but also experienced a sharp rise and cooling. Capsule curing is one of the key processes to obtain high quality performance, and it is also one of the most important processes in capsule production. The process is to first make the rubber material through the appropriate processing of semi-finished products, and then through the chemical effect, the semi-finished products made capsule shape, to meet the performance of the use of tire processing.

Capsule curing process includes mold, mold, mold, mold, and so on. Capsule vulcanizing machine controlled by the movements of the core rod, the core rod and the main oil cylinder, combined into the core mold cavity the formation of capsule vulcanizing pressure required, at the same time through the access control to control the steam curing temperature required. Most capsule curing machine adopts hydraulic system. The hydraulic pressure station controls the upper die, the lower die and the main oil cylinder by the oil pipeline.

With HOLLiAS LM series PLC analog acquisition of high precision, good ductility, network characteristics, and put forward a set of small PLC based on Hollysys capsule vulcanizing machine control system solutions. This scheme overcomes the traditional relay of capsule in curing pressure, temperature and time of the three elements of the control is not precise, high failure rate shortcomings, has a certain reference value for the application of PLC in industry capsule vulcanizing machine.

According to the input and output point requirements, select the 40 point CPU module LM3109 and 4 channel analog input module LM3310. The switching input of the control system mainly includes the operation mode switching button, the setting button and the action button. The analog input of the system includes a temperature transmitter signal input and a pressure transmitter signal input. The output of the system includes a motor, an electromagnetic valve, an indicator light, etc.. Touch screen for input parameters, while monitoring the current state of operation and time. Computer as a remote monitoring equipment, can be connected with the PLC, used to save and monitor the running state of the capsule curing machine. The control system of the capsule curing machine mainly realizes the accurate control of pressure, temperature and time in each stage of curing, the fault detection and alarm, the parameter record and communication.

The HOLLiAS LM series PLC designed a capsule vulcanizing machine temperature and pressure control system has high control precision, network interface and features rich, achieve a capsule vulcanizing machine, automation control and network management, greatly improving the capsule production efficiency and product quality, to meet the high quality, high efficiency, low failure rate etc..

PLC how to learn, how to learn for beginners PLC?

Develop a good interest

Since all of the PLC programming is not interested, then how can learn it. So it can be programmed as an interesting intellectual game, this will cause you to have enough patience and perseverance to complete the program.

PLC learning to focus on practice, there is no practice is absolutely not good. This is also the most critical learning PLC.

So when programming need as practice object PLC and related hardware equipment, it can also program intuitive response with the actual equipment action in the detection procedure, so that the error action of equipment can easily find the point of failure, or no control object, fault point to analysis, to program it is difficult to judge the correctness of.

Develop the good habit of programming

In the preparation of a slightly complex project, we need to analyze the process of the project —- that is, drawing the flow chart

In the preparation of procedures, the use of the intermediate relay to have the order and rules, otherwise the program will be very disordered, and in the future of the program changes and their troubles.

At the same time, in the preparation process, the every step, the role of each signal and the intention to mark, so you know your own programming every step of the intention, and in the process of looking back at a glance.

Often communicate with peers

PLC application and its wide range, its control function is also changing, and peer exchanges can promote the development of knowledge, and in the exchange process can reflect their own shortcomings.

At the same time when you encounter problems, the exchange is particularly important, they do not understand the technology, there may be a little hint, it will become very simple to solve.

Finally, on the network at present there are a lot of PLC learning materials and related technology, can understand the relevant technology through the network, so you can have to understand the various techniques for later use when targeted learning.