Practical work
Labs
Practical work for the course: the PLC-200 bench labs of the Lab Works booklet, where you program and test the control of each mechanism, and model labs in Python that show the dynamics the bench cannot.
PLC-200 labs (TP 0–6)
Prof. Tir's Lab Works booklet on the K&H PLC-200 trainer (Siemens S7-200 CPU 224). Each page gives the bench set-up, the I/O allocation, preparation tools, the procedure with its checkpoints and the fault-injection tests. The program is yours: no solution is given.
15 sessions of 1 h 30 · groups of two or three · one report per TP
- TP 0 · 1 session of 1 h 30Getting started with the PLC-200Connect STEP 7-Micro/WIN to the CPU 224, write and monitor a first ladder network, and prove that a normally closed STOP fails safe.
- TP 1 · 2 sessions of 1 h 30DC motor characterisation and the automatic barrierPWM speed control from the PLC, a measured speed–duty-cycle curve, and a crank-driven barrier with position switches, vehicle detection and a time-out.
- TP 2 · 3 sessions of 1 h 30Motor starters and a two-pump stationDirect-on-line and open-transition star–delta starters with overload and interlocks, then a pump station with level hysteresis, lead–lag and dry-run protection.
- TP 3 · 3 sessions of 1 h 30Four-floor elevatorA stepper-driven car with PTO acceleration ramps, encoder position check, door interlocks and safety chain, structured as a GRAFCET with SCR steps.
- TP 4 · 2 sessions of 1 h 30Hoist: brake sequencing, overload and anti-swayThe brake-release and brake-apply handshake of a hoist, a fail-safe upper limit, the graded overload response, and a zero-vibration shaper computed in the PLC.
- TP 5 · 2 sessions of 1 h 30Conveyor line and brick sortingStart and stop a line of three conveyors with warning and proof of motion, add the belt protections, and track bricks with a shift register clocked by the belt.
- TP 6 · 2 sessions of 1 h 30Capstone projectTake a machine from a written specification to a commissioned PLC program: resource allocation without conflicts, approved GRAFCET, commissioning record and an oral defence.
How each TP is marked (out of 20)
- Preparation, completed before the session: 3
- Program: correct behaviour and structure (symbols, SCR steps, comments): 6
- Bench demonstration: functions shown, every fault-injection test fails safe: 6
- Report: complete test log, questions answered from your own observations: 5
How the TPs map to the official programme
The approved programme for UEM 2.1 lists six hardware and PLC modules. This is where each one is carried out on the PLC-200 trainer:
- TP 1, Automatic barrier ↔ TP 1 Part B: crank-driven barrier on the DC motor module.
- TP 2, Drilling ↔ TP 2 (spindle motor starting, DOL and star–delta) and TP 6 project A (drilling cycle).
- TP 3, Soap marking ↔ TP 6 project B (indexing conveyor and marking stamp).
- TP 4, Door system ↔ TP 3: car-door and landing-door interlocks of the elevator.
- TP 5, Hoist ↔ TP 3 (goods lift) and TP 4 (hoist brake sequencing and overload).
- TP 6, Brick sorting ↔ TP 5 Part C: shift-register tracking and rejection of bricks.
Class resources
For the introductory session and for every lab: the presentation shown in class and the report form each group fills in.
Model labs (Python)
The dynamic behaviour the trainer cannot reproduce (starting transients, four-quadrant power flow, sway, load sharing) is modelled in these browser labs. They support the TPs' questions.
- OpenLab I · Industrial motor torque-speed characteristicsInduction motor torque-slip curve, synchronous motor torque-angle curve, shunt, series and compound DC motors, and RMS torque of a duty cycle.
- OpenLab II · VFD-driven pump with closed-loop PID controlOperating point, throttling against speed control, and a PID loop, tuned by you, that holds the discharge pressure through a 20 % drop in demand.
- OpenLab III · Four-quadrant elevator drive with S-curve profilingA seven-phase S-curve trip, the reflected torque of a counterweighted lift, the four quadrants along the trip, and the braking resistor for the worst regenerating case.
- OpenLab IV · Crane hoist braking and trolley anti-swayThe hoist raising and lowering its rated load in four quadrants, the braking resistor, and the load as a pendulum: step against shaped trolley acceleration.
- OpenLab V · Multi-motor conveyor sizing and load sharingThe Tutorial 5.1 conveyor on two drives: belt pull and power, then master-slave and droop sharing through a load surge and a lost fieldbus link.
- OpenLab VI · Capstone mini-project designYour own mechanism, from specification and control philosophy to sizing and a working simulation, checked for completeness and presented against the rubric.
Each model-lab report is marked out of 20: model correctness 6, results and plots 5, critical discussion 6, report quality 3.