Experiment No.6Introduction of each step of the process and creating an application for a PLC, loading it in PLC and use of digital outputs.

1. Run FPWIN Pro5 under Windows

2. Create a new projectSelect a configuration for the new project

3. Identify the different parts constituting the project

4. We may enter the first elements for our new program

5. Interconnect the components with the Draw Line tool and asign the X0 and Y0 addresses on the display, shown after clicking on the question mark of each component. (X and Y should be written in capitals)

6. Next, we will check the program created

7. We may load the program next

When commutting to the online mode in step 2, a pop-up window with a warning message such as “the project is not logic” may be displayed. Click on No button of the pop-up.

If there is a communication error, go to the online menu in Comunication Parameters of the tool bar, the default configuration will be 115.200bps, 8 bits for data size, and 1 bit for the stop bit.

8. We monitor the execution

10- Close the project

Now it is time to check how the practice works. In order to do so, wire the Sw0 with the DI0 (DI0 reference to X0) and activate the Sw0 switch. The DQ0 output (DQ0 reference to Y0) will be illuminated. Try to swap Y0 for Y2 in the practice project. Reload the program again in the PLCE and verify DQ2 (Y2) activates this time when activating Sw0. You may repeat the former operation substituting by YA, DQ10 will be illuminated. (A(Hexadecimal) = 10(Decimal)).

Note:

DI0 <-> X0 DQ0 <-> Y0

DI1 <-> X1 DQ1 <-> Y1

. . . .

. . DQD <-> Y13

. .

DI15 <-> XF

PLC Programmable logic controller (PLC) is a control system using electronic operations. Its easy storing procedures, handy extending principles, functions of sequential/position control, timed counting and input/output control are widely applied to the field of industrial automation control.

Ladder languageLadder logic is the main programming method used for PLCs. As mentioned before, ladder logic has been developed to mimic relay logic. The decision to use the relay logic diagrams was a strategic one. By selecting ladder logic as the main programming method, the amount of retraining needed for engineers and tradespeople was greatly reduced.

Modern control systems still include relays, but these are rarely used for logic. A relay is a simple device that uses a magnetic field to control a switch, as pictured in Figure 2. When a voltage is applied to the input coil, the resulting current creates a magnetic field. The magnetic field pulls a metal switch (or reed) towards it and the contacts touch, closing the switch. The contact that closes when the coil is energized is called normally open. The normally closed contacts touch when the input coil is not energized.

Relays are normally drawn in schematic form using a circle to represent the input coil. The output contacts are shown with two parallel lines. Normally open contacts are shown as two lines, and will be open (non-conducting) when the input is not energized. Normally closed contacts are shown with two lines with a diagonal line through them. When the input coil is not energized the normally closed contacts will be closed (conducting).

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