1 meet control requirements of the controlled object.2 in the premise of meeting the requirements to make simple, affordable, easy to use and maintenance of control system.3 ensure that the control system is safe and reliable.4 taking into account the development of the production and improvement of technology in select PLC capacity should be appropriate … Continue reading Design of PLC control system of the four cardinal principles
Category: plc program
PLC control system design of the basic principles and main contents
1. design principles In order to achieve controlled technology to improve production efficiency and product quality. 1. selection of PLC should not only meet the requirements of specification, you should also focus on technical support and after-sales service of the company's products. (Choose product) 2. to meet the control requirements of the controlled object. 3. meet the requirements of … Continue reading PLC control system design of the basic principles and main contents
Ladder diagram programming principle and PLC programming method
(1) input/output relays, auxiliary relays, timers, counters, the contacts of the device can be used repeatedly without complex programs to reduce the number of contacts.(2) the ladder each row from left buses start coil terminate in the right bus. Contacts should not be placed right of the coil(3) in addition to stepping outside of any … Continue reading Ladder diagram programming principle and PLC programming method
Representation of the PLC function instruction
Representation of the function instructionThe expression takes the following form:Figure 1 command basic forms(1) [s.] is called the source operand, its content does not change with instructions, in the case of index can be used to modify the soft components, using the "." symbol [s.] said the number of sources for a long time, [S1.][S2.] … Continue reading Representation of the PLC function instruction
PLC programming language of IEC standard IEC61131-3
PLC programming language of IEC standard (IEC61131-3) 5 programming language:1) sequential function chart (Sequential function chart);2) ladder (Ladder Diagram);3), function block diagram (Function block diagram);4) list of instructions (Instruction list);5) structured text (Structured text).Sequential function chart (SFC), ladder diagram (LD), function block diagram (FBD) is a graphical programming language, instruction list (IL), and structured text … Continue reading PLC programming language of IEC standard IEC61131-3
Step instructions and step ladder diagram examples
A, step instructions(1) the STL: step-start instructions(2) RET: step return instructionsSecond, step ladderFigure 1 shows the State transition diagram as shown in Figure 2 can be converted into a step ladderFigure 1Step ladder instruction has the following characteristics:(1) transfer for automatic reset function(2) allows dual output(3) the main control functions
What is a PLC State transfer diagram
State transition diagram and function chart, it is the State of elements are used to describe the process flow diagram. It is usually composed of the initial state, a series of General State, transfer lines and transfer conditions. Each State provides three functions: drive for loading, specifying conditions of transfer and specify the transfer destination.
Delay connect/disconnect circuit of PLC ladder diagram
Delay connect/disconnect circuit
Design method of PLC ladder diagram module
According to the modular design, modules control functions of the system, in order for the control module design of ladder diagram.For example, in the PC control system of Elevator, the elevator control functions can be divided into: door switch control modules, layer control module, the elevator control module, such as call display and control module. … Continue reading Design method of PLC ladder diagram module
Architecture and programming method of PLC
I. structure of the programmable controller1. structure of the PLC include most of the hardware and software. Three-ring between the hardware and control objects:2. first part: is the operating system, using it to manage hardware resources PLC;3. the second ring: is the build system, which had two rings of PLC software system.4. the third ring: … Continue reading Architecture and programming method of PLC
PLC ONE 