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.
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:
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
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.
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.
1, need programming software, GX Developer 8.86Q
2, need to programme cable usb-sc09-fx.
Connect the programming software and PLC with the programming cable, online transfer settings (COM port settings) PLC read check the program + parameters, click to execute. You can
Allen-bradley, AB, was initially a well-known electric company in the United States.
It is currently a brand owned by Rockwell Automation.
The SLC500 is a medium-sized PLC product from AB.
PLC (Programmable Logic Controller), programmable controller, programmable logic controller, are the same concept
PLC is AB micro logix 1500, the programming cable is USB-1761-CBL-PM02, and the programming software is RSLlogix 5000. When the PLC is connected, the PLC can be found and the PLC data can be monitored, but the upload and online are gray. Can’t download the program to the PLC？