PLC Program for Traffic Light Control Control Purpose: Enabling the traffic lights to work by Start button X0 and to stop by Stop button X1. Setting the time of red light in East-West direction as 60 sec and North-South direction with a heavier traffic as 30 sec. The time of red light in East-West direction equals to the time of “green light + green light flashing + yellow light” in North-south direction, and vice versa. When yellow light is ON, cars and pedestrians should not cross the road, and yellow light will last for 5 sec for the crossing cars and pedestrians to pass safely. · Timing diagram of traffic lights in East-West direction: Timing diagram of traffic lights in North-South direction: Devices: Device Function X0 Start button X1 Stop button T0 60 sec timer. Time base: 100ms T1 20 sec timer. Time base: 100ms T2 5 sec timer. Time base: 100ms T10 50 sec timer. Time base: 100ms T11 5 sec timer. Time base: 100ms T12 5 sec timer. Time...
Identification and Sorting of Defective Products using PLC Program Control Purpose: Detecting the defective products (taller than normal dimension) on the conveyor belt by photoelectric sensor and pushing them into the recycle box at the 5th position. The pushing pole will be reset when the falling of defective product is detected. When errors occur, the disorder memory can be cleared and the system can be restarted by pressing RESET Devices: Device Function X0 Photoelectric sensor for detecting defective products X4 Photoelectric sensor for monitoring the cam X5 Photoelectric sensor for detecting the falling of defective products X6 RESET Y0 Electromagnetic valve pushing pole PLC Program : Program Description: Every time the cam rotates once, the product will be moved from one position to another position. X4 will be activated to execute SFTL instruction once. The content in M0~M4 will be shift to left for one bit and the state of X0 will be sent to M0....