Disk Binding Machine PLC peripheral control circuit troubleshooting examples

The book binder has entered the Chinese market since the early 1990s, after more than 10 years of development. Development and improvement, the operation and control methods are more and more advanced and perfect, especially the control of the correspondence relationship between the book block and the book cover, which also solves the problem of large waste of book cover. The author here talks about the failure of the PLC peripheral control circuit during the repair process of the disk gluer and hopes to help everyone.
Fault 1: The book core, not on the book cover book binding machine book book and book cover correspondence is one by one PLC to achieve centralized control, PLC peripheral control circuit, as shown in Figure 1.
According to the phenomenon of failure to view the operation of the binder, as shown in Figure 2.

Once this fault occurs, it should be shut down immediately. Looking at the PLC peripheral input circuit, it was found that the input indicator “01” of the cover detection photoelectric switch was always on, and the fault relay output indicator “01” was off. Checking the photoelectric switch on the cover table, it was found that the corresponding mirror was dirty, forming an illusion that there was always a book cover, causing the fault relay to not act. Wipe the mirror clean, the fault is ruled out. In addition, the photoelectric switch on the cover table is not securely fixed, and such failure may also occur on the reflector when the illumination surface is not illuminated.
Fault 2: The book block is not on, the book cover has been checking the PLC peripheral control circuit and found that the input indicator “00” of the book block detection photoelectric switch has been in the bright state. Check the corresponding photoelectric switch and find that the mirror surface is covered with dust. Clean the dust and troubleshoot.
Fault 3: letter good and bad skin, down to check the state of instability <br> PLC peripheral control circuit, found proximity switch input indicator "03", "04" move irregularly with bright, erratic, and cover detector The photoelectric switch input indicator "01" and the book block detection photoelectric switch input indicator "00" light normally. Subsequently, the cam corresponding to the proximity switch was inspected, and it was found that the top thread of the cam was loose. In the course of the operation of the machine, the cam was displaced, which caused disorder of the upper cover and caused such failure. Adjust the cam according to the induction time during the normal operation of the machine, and fix the top wire and troubleshoot.
Fault 4: The book block is either on or off, and the book cover is always on
Stop inspection, first judge according to the phenomenon of failure, found that the PLC peripheral input circuit "00,," "01" indicator lights regularly, the solenoid valve output indicator "00" has been lit, determine the PLC output contacts “00” has broken down.Reprogramming input another contact, power running, troubleshooting.
In the one-to-one relationship between the bookbinding machine and the book cover, most manufacturers have adopted centralized PLC control. However, some small and individual enterprise users do not know much about PLC. Once a failure occurs, it is often Helpless, consult the manufacturer's technical staff, it is time-consuming and costly. If you can judge according to the schematic diagram, operation flow, and the lighting status of the PLC peripheral input and output indicators, troubleshooting will become easier.