Copyright Goodheart-Willcox Co., Inc. 204 Programmable Logic Controllers: Hardware and Programming • If PBR and PBG are pressed twelve times, only the white pilot light (White_ PLT) turns on. (Note that as long as the total is twelve, the White_PLT should turn on. This means that the pressing combination does not matter.) • Three timers should indicate how long each light has been on. 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.