PLC Programming Examples
Real-world PLC projects with full ladder + Structured Text code, I/O lists, and step-by-step explanations. Each example shows the full solution to a problem you'll meet on the plant floor.
Traffic Light PLC Program
Single-intersection traffic light controller with N-S and E-W phases plus all-red interval
Water Tank Level Control
Two-pump water tank with high/low level sensors, alternating pumps for even wear, high-high alarm trip
Conveyor with Photoeye Sort
Conveyor running at constant speed sorting parts by photoeye into two reject bins
HVAC Zone Temperature Control
Single-zone temperature control with PID heater output, thermostat dead-band, and occupied/unoccupied scheduling
Motor Reversing with Interlock
Bidirectional motor with start/stop buttons for forward and reverse, with software interlock preventing both contactors energising simultaneously
Batch Mixer Sequence
Three-ingredient batch process with parallel filling, weighing, mixing, and discharge using SFC-style state machine
Parking Gate Controller
Single-lane parking gate with vehicle loops, RFID/ticket trigger, gate motor with safety photoeye
Pump PID Flow Control
Centrifugal pump with VFD modulating to maintain a flow setpoint via PID control