Correspondence between program transmission speed and PLC programming tool
When the following interfaces are used between FX3U/FX3UC programmable controller and GX Development (Ver.8.13P or above), the program can be written/read and monitored at high speed (115.2 kbps).
FX-30P can communicate wi...
There are many kinds of PLC products, and their specifications and performance are also different. The classification of PLC is generally based on the difference of its structure, function and I/O points.
1. Classification by structure
According to the structure of PLC, PLC can be divided into tw...
The PLC can be specified to perform a limited number of scans on the program (from 1 scan to 65535 scans). By specifying the number of scans the PLC runs, the change of program process variables can be monitored. At the first scan, the SM0.1 value is 1. 1. Execute a single scan “single scan...
The difference between IPC and PLC is not in their looks, nor in their working environment, but in their functions. As far as development is concerned, they come from different ways. PLC comes from electrical logic control characterized by relay, and industrial control computer comes from compute...
Practice has proved that most of the failures of PLC products are caused in the manufacturing process. In the manufacturing process, the most important thing to ensure the reliability and stability of products is product testing. Only through complete and comprehensive testing can problems in pro...
How to use the inverter properly
The connection of PLC and inverter becomes the key to the success of the system.
1. PLC switch command signal input
The input signal of the frequency converter includes switch type command signals for operation of running/stop, forward/reverse rotation, inching an...
Switching value: there are only two states of switching value, 0 and 1, including input and output, which reflect the state.
Digital quantity: digital quantity is composed of multiple switching quantities. For example, three switching values can form a digital value representing eight states.
Ana...
PLC control system and DCS control system are not a concept on a logical level. It can be seen from the name that PLC is named by function and DCS is named by architecture. In principle, PLC can form DCS. Of course, there are still performance differences between the two, depending on the product...
PLC control system and DCS control system are not a concept on a logical level. It can be seen from the name that PLC is named by function and DCS is named by architecture. In principle, PLC can form DCS. Of course, there are still performance differences between the two, depending on the product...
1. PLC is a relatively mature control system composed of single chip microcomputer, and it is the product of a mature and stable single chip microcomputer application system that has been debugged. It has strong universality.
2. Microcontroller can constitute a variety of application systems, wit...
PLC programming is an electronic system for digital operation. It uses programmable memory to store the instructions for executing logic operation, sequence control, timing, counting and arithmetic operation, and control various types of machinery or production processes through digital and analo...
Design principle of PLC control system
(1) Practicability
Practicality is the basic principle of control system design. While studying the controlled object, engineers should also understand the use environment of the control system, so that the designed control system can meet all the requiremen...
DCS power off correctly
When the DCS needs to be powered off for maintenance due to overhaul or other reasons, we often directly power off the DCS, but sometimes this non-standard operation will bring serious consequences, such as configuration loss, PID parameter loss, etc. Therefore, it is nece...
There are many kinds of PLC products, and their specifications and performance are also different. The classification of PLC is generally based on the difference of its structure, function and I/O points.
1. Classification by I/O points
(1) Small computer. The total number of input and output poi...
For the PLC controller power supply, should use non-power line power supply, directly from the low-voltage distribution room on the main bus using a special line power supply. Choose isolation transformer, and transformer capacity should be larger than the actual needs of about 1.2 to 1.5 times, ...
In the actual commissioning process, sometimes there is such a situation, a software system from the theoretical extrapolation can fully meet the process requirements of machinery and equipment, and in the operation process in any case can not be put into normal operation, in the process of syste...
1.Output mode selection
(1) relay output: the advantage is that different common points can be brought between different AC and DC loads, and the voltage can also be different, with load current up to 2A / point; but the relay output mode is not suitable for high-frequency action of the load, whi...
1.Storage capacity
Storage capacity refers to the capacity of the user program memory. The capacity of the user program memory is large enough to prepare complex programs. Generally speaking, the user memory capacity of small PLC is several thousand words, while the user memory capacity of large ...
1、 Maintenance procedures, regular equipment testing and adjustment regulations
(1) Check the connection of the wiring terminals in the PLC cabinet semiannually or quarterly, and if any looseness is found, re firmly connect it in time;
(2) Re measure the working voltage of the power supply in th...
The difficulty of core making has always been a hot topic in the past two or three years. Domestic enterprises are also speeding up to make up for the shortcomings of chip design. However, in the high-performance CPU market, there is not much successful experience in China. As ye Tianchun, direct...