Learn · Build · Automate
Practical PLC, automation, mechatronics and embedded tutorials from a working engineer. Wire it, program it, understand why it works.
Popular: Ladder timers Modbus Sensors ESP8266 VFD
LD X0
OR Y0
ANI X1
OUT Y0This is a full build-along tutorial that goes beyond the Bob Teaches Tech YouTube video. It covers the hardware, wiring, GX Works2 project setup, and explains each step of an automatic timer loop sequence on a Mitsubishi FX3U PLC. You'll…
Each path is an ordered list of tutorials. Finish one and you can wire, program and troubleshoot that system on your own.
Ladder logic, timers, counters and your first working machine sequence.
Modbus RTU/TCP, Ethernet/IP and reading real device registers.
NPN vs PNP, 4–20 mA loops, encoders and safe panel wiring.
ESP8266/ESP32 and Arduino projects that talk to real equipment.
Explainers, wiring diagrams and build-along tutorials.
21 guidesExplainers, wiring diagrams and build-along tutorials.
12 guidesExplainers, wiring diagrams and build-along tutorials.
9 guidesExplainers, wiring diagrams and build-along tutorials.
6 guidesA working PLC simulator in your browser. Inputs, contacts, coils and timers scan just like a real controller, so you can see why a seal-in or an interlock behaves the way it does.
LD X0
OR Y0
ANI X1
OUT Y0
LD Y0
OUT T0 K50
LD T0
OUT Y1Inductive, capacitive, and photoelectric sensors all answer the same basic question, is something there?, but they sense completely different physical properties, and…
SCADA lets a single operator monitor and control equipment spread across an entire plant, pipeline, or utility network — here's what the…
Arduino digital I/O explained: pinMode, digitalRead, and digitalWrite with a tested button-and-LED wiring and code example.
Structured text (ST) is the IEC 61131-3 language that feels most familiar to anyone with a Pascal or C background - and…
Modbus register types explained: coils, discrete inputs, holding and input registers, function codes, and addressing conventions.
Step-by-step guide to connecting a PLC to SCADA over Modbus TCP, including port 502 setup and a troubleshooting table.
Quick answers for the bench: every result shows the formula, so you learn the method as well as the number.
Learn the fundamentals of ladder logic programming, from basic wiring, I/O configuration to functional ladder logic.
No. Most tutorials work with free simulators, and the Ladder Lab on this site runs in your browser. Where hardware helps, the parts list says exactly what to buy.
Yes. Tutorials, the glossary and the calculators are free. Some downloads ask for your email so you get the files and the next tutorial.
The concepts are vendor-neutral. Examples use common platforms such as Siemens, Allen-Bradley, Delta and OpenPLC, and each tutorial lists what it was tested on.
Yes. Use the Work with me page to describe your project, team training or writing request.
I am Bob Odhiambo, a mechatronics and automation engineer. I program and commission PLCs, work with industrial networks and VFDs, and write for Control.com and EEPower. Everything here is built and tested on real hardware.
Pick a tutorial, wire it up, and get the next one in your inbox.
