Copyright Goodheart-Willcox Co., Inc. Chapter 6 PLC Programming 107 +120 V I0 I1 I2 I3 I4 I5 I6 I7 I8 I9 I10 I11 Input ports Common O0 O1 O2 O3 O4 O5 O6 O7 Output ports Stop RPB GPB TSW M1 Motor #1 M2 Motor #2 White light W Goodheart-Willcox Publisher Figure 6-30. Input/output connections for Figure 6-29. Goodheart-Willcox Publisher Table 6-6. Input/output ports assignments for Figure 6-28. Input Ports Output Ports Stop = I:0/0 Motor #1 = O:0/0 Red pushbutton (RPB) = I:0/1 Motor #2 = O:0/1 Green pushbutton (GPB) = I:0/2 White light = O:0/2 Temperature switch (TSW) = I:0/3 Place the PLC in the offline mode and create the ladder logic diagram displayed in Figure 6-31. Download the program into the PLC and place the PLC in the run/online monitor mode. Use the following steps to force some of the input instructions ON and OFF. These steps will familiarize you with the use of the force instruction. 1. Right-click input I:0/3 to open the shortcut menu. Click the Force On command to place the word ON below the input instruction I:0/3. See N Figure 6-32. 2. Click Enable Force and notice that the word ON under the input instructions N changes to red. The red ON is an indication that the force instruction is N enabled. You have just used the force instruction to close the normally open input I:0/3. Therefore, the white light turns on to indicate continuous run mode. See Figure 6-33. 3. Right-click instruction I:0/1 and click Force On from the shortcut menu to force the input instruction I:0/1 to close. Both outputs should turn on and run continuously.