An example of using FGs to implement an application through staircase lighting control. This building has one ground floor and three above ground floors, each with button controlled light switches. Quickly press one of these buttons, and all four lights inside the staircase will turn on and continue to illuminate for 5 minutes.

These buttons are respectively connected to the four input points X0, X1, X2, and X3 of the PLC. Four lights are controlled through a relay output point Y0 on the PLC.

图1 wiring diagram

Double click the shortcut on the desktop, or click SamSoar2022.exe in the SamSoar2022 program group on the Start menu to run the configuration software.

Enter the running interface of SamSoar2022 programming tool as shown in Figure 1.2.

图2 software page

Before starting to write a new program, it is necessary to create a new or open an existing project that includes necessary definitions and a small number of configuration parameters.

If the project does not already exist, click the New button at the top.

图3 new butoon

Pop up a window to set properties, click OK. This project sets the model.

图4 New window

Click the open button at the top.

图5 open button

Select the open file and click OK。

图6 open window

Click to expand the command and its sub items in the left project management window.

Click on the first graphic element position on the left side of the editable position of network 0, select and double-click the normally open contact to add the command at the selected position, double-click the added graphic element, and a ladder diagram input dialog box will pop up. Enter X000 and confirm.

Select the "Insert Row" button in the standard toolbar to add a row. Click to select the second element position on the left side of the first row, and select the "Vertical Line" button in the ladder diagram toolbar to add a vertical line.

Click to select the position of the graphic element on the left side of the second row, select and double-click the normally open contact to add the command at the selected position, double-click the added graphic element, and a ladder diagram input dialog box will pop up. Enter X001 and confirm.

Add the third and fourth lines in sequence, and enter X002 and X003 respectively in the ladder diagram input dialog box and confirm.

Click to select the rightmost element position in the first row, select and double-click to turn on the delay timer TON and add the command at the selected position. Double click the added element to pop up the timer input dialog box.

The data for input parameter T is K0, and the data for input parameter SV is K3000, please confirm.

Click to select the rightmost element position in the second row, and select the "Vertical Line" button in the ladder diagram toolbar to add a vertical line.

Select and double-click on 'Set Output Coil', add the command at the selected position, double-click on the added graphic, and the output coil input dialog box will pop up.

The operand for input parameter BIT is Y000, and the data for input parameter N is K1. Confirm.

Click to expand the command and its sub items in the left project management window.

Click to select the first graphic element position on the left side of Network 001 for editing. Select and double-click the normally open contact to add the command at the selected position. Double click the added graphic element to pop up the ladder diagram input dialog box. Enter T0 and confirm.

Click to select the rightmost graphic element position, select and double-click [Reset Output Coil], add the command at the selected position, double-click the added graphic element, and the output coil input dialog box will pop up.

The operand for input parameter BIT is Y000, and the data for input parameter N is K1. Confirm.

At this point, the editing of the ladder diagram project file is complete. Select the "Save Project" button in the standard toolbar to save the ladder diagram project file. After the project is stored, you can download the program to the PLC.