PLC Practice Questions & Worked Solutions
A companion workbook to PLC Pulse — 81 exam-style problems across 12 topic areas, each paired with a complete worked solution. Truth tables, Karnaugh maps, ladder diagrams and timing diagrams are shown in full, so you see the reasoning, not just the answer.
How this workbook is organised
Practise every concept, then check your work
Each section below collects the practice questions for one topic area of the course. Attempt a question fully on paper first — then open its worked solution to compare your method. Every solution is written so a beginner can follow each step from the truth table through to the finished ladder diagram.
PLC Fundamentals, Hardware & Theory
NEMA definition, opto-isolators, DC input and output modules, selection criteria and the four-phase scan cycle.
View questionsBoolean Algebra & Number Systems
Boolean proofs, Karnaugh-map minimisation, SOP and POS forms, and conversions across BCD, octal, hex and Gray code.
View questionsDigital Logic Circuits & Gate Conversions
Comparators, multipliers, decoders, flip-flops, seven-segment logic and universal NAND/NOR conversions in ladder.
View questionsLadder Logic Programming Basics
XOR rungs, POS-form logic, relay-to-ladder translation, push-on/push-off control and rung debugging.
View questionsMotor Control
Start/stop seal-in circuits, two-hand safety, jog mode, forward/reverse interlocks and sequential motor control.
View questionsConveyor & Process Control
Fallen-bottle detection, pump systems, two-tank filling, box counting, workcell logic and process sequencing.
View questionsAlarm & Safety Systems
Multi-input factory alarms, burglar-alarm logic, vessel overfill detection and car door / seat-belt interlocks.
View questionsTiming, Counting & Sequencing
ON/OFF-delay pulse trains, cascaded counters, a 24-hour clock, frequency measurement and scan-rate monitoring.
View questionsPulse Width Modulation (PWM)
Duty-cycle control from 0–99, timer-based pulse generation and constructing the corresponding output waveform.
View questionsTraffic Light Control
A fixed RED → GREEN → YELLOW sequence with a one-time power-up safety phase using retentive memory.
View questionsPriority, Selection & Industrial Applications
Quiz-buzzer first-press lockout, read-only status checking and Celsius-to-Fahrenheit conversion in ladder.
View questionsWaveform Analysis, Tracing & Diagnostics
Designing ladder from waveforms, timing-diagram tracing, ladder-to-Boolean conversion and fault diagnosis.
View questionsSection pages are published progressively — each card links through as its page goes live.