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IEC 61131-3 Reference

IEC 61131-3 Standard Function Blocks: Quick Reference

Quick reference of IEC 61131-3 standard function blocks: timers (TP, TON, TOF), counters (CTU, CTD, CTUD), edge detection (R_TRIG, F_TRIG), bistable (SR, RS). With Siemens S5/S7 equivalents.

6 min readIEC 61131-3function blocksTP

IEC 61131-3: The PLC Programming Languages Explained

Overview of the IEC 61131-3 standard and its programming languages: Ladder Diagram (LD), Function Block Diagram (FBD), Structured Text (ST), Sequential Function Chart (SFC), and the deprecated Instruction List (IL). With Siemens equivalents.

10 min readIEC 61131-3programming languagesLD

IEC 61131-3 Data Types for PLC Programmers

Reference table of all IEC 61131-3 data types: BOOL, BYTE, WORD, DWORD, INT, DINT, REAL, LREAL, TIME, STRING, ARRAY, STRUCT, UDT. With bit widths, ranges, and Siemens S7 availability.

8 min readIEC 61131-3data typesBOOL