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Anonymous users2024-02-06The power light of the plc is on, but the run light is not on, that is, there is no running program.
It may be due to the following reasons:
1. The toggle switch on the PLC, if not, dial to RUN, if not, dial to RUN.
3. There is a program, the toggle switch is also running, and the PLC operation can be controlled by programming software. This can be done by turning the toggle switch to stop on the hardware, and it can also be dialed back to run.
4. Look at whether the alarm error light is on, if the alarm light is buried, it means that the alarm is called, and the program will not be run when the alarm is called, so the run light will not be on, first release the alarm and run again.
5. See if there is a vertical return order to stop the PLC operation in the program, some PLCs have done some procedures such as dunning, and the time is up to control the PLC not to run.
6. If none of the above is true, it should be that the PLC is broken.
Programmable logic controllers.
Programmable Logic Controller (PLC), a type of computer with a microprocessor.
The digital operation controller for automatic control can load control instructions into memory at any time for storage and execution. Programmable Controllers.
It is composed of CPU, instruction and data memory, input and output interfaces, power supply, digital and analog conversion and other functional units.
The early programmable logic controller only had the function of logic control, so it was named programmable logic controller, and later with the continuous development, these computer modules with simple functions have included logic control, timing control, analog control, multi-machine communication and other functions, and the name was also changed to programmable controller.
However, due to the conflict between its abbreviation PC and the abbreviation of personal computer, and for reasons of habit, people still often use the term programmable logic controller, and still use the abbreviation PLC.
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Anonymous users2024-02-05There can be a variety of reasons why Mitsubishi PLC communication can't be read, here are some common problems and solutions::
1.Communication parameter setting error: The communication parameters include communication protocol, communication port, baud rate, etc., which need to be consistent with the PLC settings for normal communication. Check whether the communication parameters are correct and ensure that the communication connection is normal.
2.Wrong address setting: When communicating with PLC, you need to specify the register address and number of registers to be read, and if the address is set incorrectly, the correct data cannot be read. Check that the address settings are correct and that the address mapping relationship is correct.
3.Communication command error: PLC communication command includes read command, write command, etc., if the command is set incorrectly, the data will not be read correctly. Check whether the Tongkuan Liangshan Xun command is correct and ensure that the communication command is in the correct format.
4.Incompatible communication protocols: PLC communication protocols of different brands and models may be different, and if incompatible communication key positive protocols are used, normal communication will not be possible. Check whether the communication protocol is correct and make sure that the communication protocol is compatible with the PLC.
5.PLC failure: If the PLC itself has a fault, such as a power failure, CPU failure, etc., normal communication will not be possible. Check if the PLC is working properly and make sure the PLC is not faulty.
6.Other reasons: There may be other reasons that cause the PLC communication to fail to read the data normally, such as network failure, hardware failure, etc. A thorough review and troubleshooting is required.
You need to troubleshoot the problem based on the specific situation, locate the cause of the problem, and take appropriate solutions.
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Anonymous users2024-02-04In structured programming, you need to use interrupts as follows:
1. Create a new task:
2. Assign a POU to the newly created task
3. Set the properties of the interrupted task
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Anonymous users2024-02-03The interrupt system on the PC can be used to perform a number of different controls. Its purpose is to interrupt a task that is currently being performed and temporarily replace it with a more immediate action. All interruptions run at high speeds.
Interrupted use can be an alarm system. Standard programming techniques take care of most situations. For example, if there is a spike or low in power** from a plant management computer, you must immediately know about this situation, and a second power source will switch in immediately.
If an uninterruptible power supply (URS> is used, this type of warning causes the user to store those computer files that are in use. Initial power spikes or shortages can occur within a very short period of time. This requires some form of high-speed "execution", which necessitates the use of interrupt elements.
This is a special operation, and not all components can be used to start or call interrupters.
Mitsubishi PLC programming program how to write PLC Hello, 1, after the program is written, you need to transform the program first, there are three ways to transform: the first is to press the F4 key of the keyboard directly, the second is to click the "transform" menu bar, and then click the first item "transform", the third is to click the "program transform" button of the toolbar, we choose the appropriate transformation method according to their own habits 2, after the program is transformed, you need to check whether there are syntax errors in the program, This check only self-diagnoses the syntax, not the design content. To check the program, click "Program Check" in the menu bar of the tool. >>>More
These two are mainstream PLCs, one made in Japan, one made in Germany, I have used both, both are very representative, it is recommended to learn both, you can learn Mitsubishi's first, because most of the programming methods of other brands of PLC are imitation of Mitsubishi, especially domestic brands, just like the Delta I use now, and Xinjie, which is almost exactly the same as Mitsubishi. Mitsubishi is what a traditional ladder looks like. And Siemens is also unique, although he also said that it is a ladder diagram, but his is a modular ladder diagram, which looks more intuitive than Mitsubishi's, and the step7 software is also very easy to use. >>>More
TO is to write the command of the special function module, that is, to send the data in the PLC to the special function module and buffer memory BFM. >>>More
The number of numerators can be registered.
d, for example, out c235 d0, and then use the screen to enter the value of d1d0. Because C235 is a 32-bit counter. >>>More
The full name of Mitsubishi Heavy Industries in China is: Mitsubishi Heavy Industries (Shanghai) Air Conditioning System ****, which was established by Mitsubishi Corporation in 2003. >>>More