Industrial automation encyclopedia

The basic structure of a Programmable Logic Controller (PLC): CPU, I/O modules, power supply and communication.

The read-inputs → execute-program → write-outputs steps a PLC repeats every cycle, and why scan time matters.

The two basic types of PLC I/O, signal levels (24V DC, 4-20 mA, 0-10 V) and their typical uses.

The closed-loop structure of a servo system: drive, motor and feedback (encoder) for precise speed/position/torque control.

The difference between incremental and absolute encoders used for servo feedback, and selection criteria.

The role of the three terms of PID (Proportional-Integral-Derivative), the basis of industrial control, and tuning logic.

The role of the power-switching stage that drives the motor in frequency inverters, typical fault symptoms, and the board-level repair approach.

The basic blocks of the drive that controls AC motor speed by changing frequency: rectifier, DC link and inverter stage.

The difference between scalar (V/F) and vector (FOC) control methods in drives, and which to choose for which application.

How the energy the motor generates during deceleration returns to the DC link, overvoltage faults, and the role of the brake resistor.

PROFINET, EtherCAT, EtherNet/IP and Modbus TCP compared by speed, synchronization and typical use.

The fundamentals of the Ethernet-based PROFINET protocol, its device-naming logic, and field commissioning tips.

The 'processing on the fly' principle of the high-speed, low-latency EtherCAT protocol and its motion applications.

The serial (RTU) and Ethernet (TCP) variants of Modbus, industry's most common open protocol, its register logic and common issues.

The Object Dictionary, PDO/SDO logic and typical use of the CANopen protocol built on the CAN bus.

The advantages and working logic of IO-Link, which provides point-to-point smart communication at the sensor/actuator level.

The working principle, use cases and commissioning notes of Safe Torque Off, the most fundamental drive safety function.

The SIL (IEC 62061) and PL (ISO 13849) concepts that define risk-reduction levels in machine safety.

How it differs from a standard PLC, its redundant dual-processor architecture, and why a separate controller runs safety functions.

The sensing principle of the two common proximity sensors, which materials each detects, and selection criteria.

Automated inspection with industrial camera systems: the basics of the lighting, lens, sensor and processing chain.

The process of removing and re-soldering BGA (Ball Grid Array) components, required equipment and critical caveats.

The four thermal zones of the reflow method used to solder SMD components and why the correct profile matters.

How the invisible threat of ESD damages electronics during board repair, and the precautions taken in the lab.

The ageing symptoms and effects of the electrolytic capacitor, the most commonly failing component in drives and power supplies.

The systematic diagnostic flow of a faulty board in the lab: visual, supply, measurement and load testing.