Архитектура PLC: CPU, power supply, rack and modules
Цель: Изучить тему «Архитектура PLC: CPU, power supply, rack and modules» и закрепить её практическими заданиями и самопроверкой.
2 акад. часа чтение и разбор теории, решение задач, работа со схемой или виртуальным стендом и проверка понимания.
Основной материал
Typical modular PLC includes power supply, CPU, digital inputs, digital outputs, analog inputs, analog outputs, communication modules and sometimes special technology modules.
CPU
CPU executes operating system and user program, manages communication, diagnostics and memory. It has work memory, load memory and retentive areas depending platform.
Backplane/rack
Modules communicate through internal bus. Addressing may depend on slot or configured hardware. Incorrect configuration produces diagnostic fault even if physical wiring correct.
Redundancy
High-availability systems can have redundant power supplies, CPUs or networks. Redundancy is not achieved simply by duplicating hardware; switchover logic and common-cause failures must be considered.
Практическая работа
Build architecture for 64 DI, 32 DO, 16 AI, 8 AO, Ethernet and Modbus RTU. Determine module categories, not exact part numbers.
Самопроверка
• What does CPU manage?
• What is backplane bus?
• Why hardware configuration matters?
• What modules process analog signals?
• Why redundancy requires system design?
Что нужно запомнить
- Typical modular PLC includes power supply, CPU, digital inputs, digital outputs, analog inputs, analog outputs, communication modules and sometimes special technology modules.
- CPU executes operating system and user program, manages communication, diagnostics and memory.
- It has work memory, load memory and retentive areas depending platform.
- Incorrect configuration produces diagnostic fault even if physical wiring correct.
- High-availability systems can have redundant power supplies, CPUs or networks.