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.

Why does the other output flash when the Mitsubishi plc presses the total stop button?

Although the total stop is pressed, the user program in the plc is still running, and when the condition is satisfied, the corresponding result is output according to the user control program and the external input condition.
Should not be a problem with plc itself, most of which is caused by an abnormal external input signal.

How to write a PLC programming button to control a motor, when the button is pressed, the motor starts, then press the button, the motor stops.

Start and stop the motor with a single button. It can be programmed by the working principle of PLC’s sequential scanning. The working process of PLC is simply

First, the input sampling phase. PLC sequentially scans the state of the input terminals and stores the state of each input point in the input image register.

Second, execute the user program. For the ladder diagram, it is scanned first, then, and from turned left to right. The state of each touch of contact needs to be logically operated with the result of the previous logical operation, and the result is stored in the component image register or the output image register.

Third, the output is refreshed. The state of each point in the output image register is sent to the output latch, and the output latches drives the load of each output relay through the output terminal.

There are numerous methods, and the counter can of course be realized, but I don’t think it is necessary to kill the chicken with a knife! Here I only give three examples of the S7-200 PLC. See below:

Mitsubishi plc, how to write programs with alternate and STL instructions, press the button to stop, press the button to start, start to go backwards in the stop position

In the stepping program, the simpler way is to use the pause switch as the normally closed one as the next trigger condition in the stepping program, and the other trigger conditions are connected in series, but only if it is done at each step. Pause, not stop where you want to stop

How does Mitsubishi PLC control the size of the ladder diagram?

Here is mitsubishi plc programming examples

After zooming in on the view, it cannot be displayed in full screen.

Can not control the size of the ladder, can only change the size of the annotation and the number of contacts displayed in each row;
The number of contacts in the menu bar – “Tools -” option, pop-up dialog box point program editor – “ladder -” ladder diagram,
Select the number of display contacts in the display format,
It is recommended to choose 13 or 11.

Mitsubishi plc ladder control

This is the control requirement I saw on the tutorial: I asked to press the start button X1, the red light Y1 lights up for 5 seconds, then the yellow light Y2 lights for 3 seconds, then the green light Y3 lights for 6 seconds, and finally returns to the red light, so Loop control. The ladder diagram is as follows, but the simulation results on the Mitsubishi plc simulation software are not the same as the control requirements in the title. Is the program wrong?

X0 is the manual automatic selection. When automatic is enabled, the X1 conveyor roller is automatically operated. When manual is enabled, the conveyor roller is manually operated after pressing X2. Y0 is the conveying roller operation.