First, the purpose of training
1. Master the application of state thinking programming to solve the sequence control problem, and transform the relay contactor control system of sequence control into PLC control system by using PLC technology.
2. Understand the three elements of state
3. Understand the characteristics of the state transition diagram (SFC)
4. Understand the realization of state transition diagram.
5. Master the programming principle and method of single-process state transition diagram.
6. Master the debugging means of state transition program.
Second, the training equipment
1. 1 set of programmable controllers (FX2N type);
2. Signal lamp (motor starts and stops in sequence) 1 Analog display module (with indicator lamp, connection port, button, etc.). );
3. 1 training console:
4. 1 set of common tools for electricians;
5. 1 computer (with programming software);
6. Connect several wires.
III. Training Contents and Guidance
1. Control requirements
The relay contactor control circuit shown in figure 1 is transformed into a PLC control system, in which the motors are started in sequence and stopped in reverse order.
Figure 1 Motor Sequential Start and Reverse Stop Control Circuit
2. Input-output allocation
According to the system control requirements, the input and output ports of PLC are determined.
3. System wiring
According to the system control requirements and I/O point distribution, draw the system wiring diagram of the motor.
4. programming; arrange
According to the control requirements, the state transition diagram and ladder diagram programs are designed.
5. System debugging
(1) input program
Input PLC correctly through computer ladder diagram.
(2) Static debugging
Connect the input equipment correctly according to the I/O wiring diagram of PLC, carry out analog static debugging of PLC, and observe whether the output indicator lamp of PLC indicates as required, otherwise, check and modify the program until the indication is correct.
(3) Dynamic debugging
According to the I/O wiring diagram of PLC, correctly connect the output equipment, carry out no-load debugging of the system, and observe whether the motor can start and stop in reverse order according to the control requirements. Otherwise, check the circuit or modify the program until the control requirements are met.
IV. Training Report
1. Training summary
(1) Run the debugging program, observe whether the running results meet the requirements, and draw its corresponding ladder diagram.
(2) Understand the principles, methods and skills of state programming.
2. Practical thinking
(1) What is the difference between using OUT instruction and using SET instruction when programming with state method? .
(2) If the manual motor control is changed to the automatic motor control, the interval is 5s: that is, press the start button to start the M 1, M2 and M3 motors in turn, and the interval is 5s; When the stop button is pressed, the three motors M 1, M2 and M3 stop in turn, and the reverse sequence interval is 5s. How to modify the program and debug it?
Verb (abbreviation of verb) training evaluation