Copyright Goodheart-Willcox Co., Inc. Chapter 9 PLC Counter Instructions 205 L AB ACTIVIT Y 9B PLC Counter and Timer Instructions This lab activity can be found in the Lab Manual as Lab Activity 9-3. Objective In this activity, you will create three PLC ladder logic diagrams for circuits that use counter and timer instructions. Then, you will verify the operation of the PLC ladder logic diagrams on your PLC lab station. Equipment • Allen-Bradley SLC 500 series PLC trainer • Single-pole, single-throw (SPST) switch • Temperature switch • Normally open pushbuttons (2) • Green pilot light and red pilot light • Bell (6-volt) • Split-phase AC induction motors (2) (fractional horsepower) Procedure Activity 1 In this activity, you will create a PLC ladder logic diagram that closes a tempera- ture switch (TSW) to start the following sequence of events. Use the black switch (SWB) to reset. • Motor one (M1) runs for three seconds. • Then, motor two (M2) runs for five seconds. fi • Finally, the bell rings three times. Step 1. Draw the relay logic diagram for this circuit. Step 2. Assign PLC input/output ports to the devices. Then, complete the PLC I/O connections on your PLC lab station. Step 3. Use the Rockwell RSLogix 500 software to create the PLC ladder logic diagram. Step 4. Download the PLC ladder logic diagram into the PLC station. Place the PLC in the run/monitor mode. Step 5. Demonstrate your working PLC system for your instructor.