---
title: "English lessons"
url: https://modsengineeringmath.com/learn/en/
site: "Mod's Engineering Mathematics (อาจารย์มด)"
language: en
updated: 2026-10-14
---

> English editions of Ajarn Mod's industrial electrical courses: AC motor control with magnetic contactors, star–delta starters, soft starters and VFDs, and PLC automation with ladder logic, timers, sequential control, analog PID and VFD control — written for the 230/400 V 50 Hz systems of Thailand, Laos, Cambodia, Vietnam, Myanmar, Malaysia and Singapore.

Markdown copy of https://modsengineeringmath.com/learn/en/ for AI assistants and search tools. Math is LaTeX ($…$ and $$…$$); interactive labs and figures are only on the web page.

# English lessons

THภาษาไทยENEnglish
// English editions · industrial electrical engineering


Two complete courses translated from the Thai originals, with the same diagrams, formula IDs, calculators and simulators. Every example uses the 230/400 V 50 Hz low-voltage supply shared by Thailand, Laos, Cambodia, Vietnam, Myanmar, Malaysia and Singapore, so the device ratings and settings apply directly in all of these countries. Use the ไทย / EN switch at the top of any page to jump to the same page in the other language.

Chapter 21 · 15 pages

### AC Motor Control with Magnetic Contactors and VFDs
Induction motor principles and nameplates, the 400 V 50 Hz supply and earthing, star and delta connections, contactors and overload relays, IEC symbols, DOL and reversing starters, a detailed star–delta starter, soft starters, applied circuits, VFD principles and set-up, design, installation and troubleshooting, plus a starting simulator.
Open the course Star–delta VFD Simulator

Chapter 22 · 11 pages

### Industrial Automation with PLCs
PLC hardware and the scan cycle, sink/source I/O wiring, ladder logic, timers and counters, the IEC 61131-3 languages, PLC motor control including star–delta, sequential control and SFC, analog signals, PID and VFD control, commissioning and machine safety, plus a ladder simulator.
Open the course Ladder basics Ladder simulator

Short English articles with worked examples (Laplace transform, vectors, power factor, matrices, PID) are in the English articles.

The Thai library with all other subjects (calculus, linear algebra, Laplace, control systems, power electronics, solar PV, power systems, sensors) is at คลังความรู้ (Thai).