PLC-Ladderiec-61131-3
10 posts
PLC Online Compiler: Write, Compile and Verify IEC 61131-3 in the Browser
What a PLC online compiler checks and why it matters: types, timer instances, duplicate coils and unreachable logic — compile IEC 61131-3 free in the browser.
Function Block Diagram Symbols: Every Standard Block and What Its Pins Mean
Every standard FBD symbol explained pin by pin: AND, OR, NOT, TON, TOF, TP, CTU, CTD, R_TRIG, SR/RS, MOVE with EN/ENO and comparators — with ST equivalents.
Structured Text Examples: 10 Real PLC Programs Explained Line by Line
Ten structured text programming examples for PLC: start/stop, timers, counters, CASE state machines, FOR loops, scaling and alarms — explained line by line.
FBD vs Ladder Logic: Which PLC Language for Which Job
FBD vs ladder logic compared honestly: same underlying logic, different readability. Which language fits interlocks, analog, sequences — and when to mix.
Function Block Diagram Symbols: Every Standard Block and What Its Pins Mean
A reference to FBD symbols in IEC 61131-3: AND, OR, TON, TOF, TP, CTU, CTD, R_TRIG, SR, RS, comparators and math blocks, with every pin explained.
FBD Programming Examples: 8 Real Circuits Explained Block by Block
Eight FBD programming examples explained block by block: seal-in, timers, flasher, counter, comparator, hysteresis alarm, edge detection and scaling.
Structured Text (ST) PLC Programming: Syntax and Examples
Structured Text (ST) for PLCs: variables, IF/CASE, loops, timers and function blocks, with real examples and when to choose ST over ladder.
Ladder Logic for Beginners: Rungs, Contacts, Coils and the Scan Cycle
Ladder logic explained for beginners: rungs, contacts, coils, the PLC scan cycle, series AND, parallel OR, and the seal-in circuit with examples.
Function Block Diagram (FBD) PLC Tutorial, with Examples
Learn Function Block Diagram (FBD) PLC programming step by step: blocks, pins, wires, execution order and when FBD beats ladder logic, with worked examples.
What Is a Function Block Diagram? FBD Definition and Basics
What a function block diagram (FBD) is in IEC 61131-3: blocks, pins and wires, how FBD relates to ladder logic, and where each view wins.