JANCD-SR50-485771
從結構上分，PLC分為固定式和組合式(模塊式)兩種。同定式PLC包括CPU板、I/0板、 顯示面板、內存塊、電源等，這些元素組合成一一個不可拆卸的整體。模塊式PLC包括CPU模 塊、I/0模塊、 內存、電源桃塊、底板或機架，這些模塊可以按照- -定 規(guī)則組合配置.3 CPU 的構成CPU是PLC的核心，神經中樞的作用，每孌PLC至少有一-個CPU，它按PLC的系統(tǒng)程序 賦予的功能接收并存貯用戶程序和數(shù)據(jù)，用掃揭的方式采集由現(xiàn)場輸入發(fā)置送來的狀態(tài)或數(shù) 據(jù)，并存入規(guī)定的寄存器中，同時，診斷電源和PLC內部電路的工作狀態(tài)和編程過程中的語 法錯誤等。進入運行后，從用戶程序存貯器中逐條讀取指令，經分析后再按指令規(guī)定的任務 產生相應的控制信號，去指揮有關的控制電路。CPU主要由運算器、控制器、寄存器及實現(xiàn)它們之間聯(lián)系的數(shù)據(jù)、控制及狀態(tài)線構成， CPU單元還包括外圖芯片、線接口及有關電路。內存主要用于存儲程序及數(shù)據(jù)，是PLC不可 缺少的組成單元。在使用者看來，不必要詳細分析CPU的內部電路，但對各部分的工作機制還是應有足夠 的理解。CPU的控創(chuàng)器控制CPU工作，由它讀取指令、解釋指令及執(zhí)行指令。但T.作節(jié)奏由震 蕩信號控制.運算器用于進行數(shù)字或邏輯運算，在控制器指揮下工作。寄存器參與運算，并 存儲運算的中間結果，它也是在控制器指揮下工作。

JANCD-SR50-485771
In terms of structure, PLC is divided into fixed type and combined type (modular type). The same type PLC includes CPU board, i/0 board, display panel, memory block, power supply, etc. these elements are combined into a non removable whole. Modular PLC includes CPU module, i/0 module, memory, power peach block, backplane or rack. These modules can be combined and configured according to certain rules 3 composition of CPU
CPU is the core of PLC and the role of nerve center. Each PLC has at least one CPU. It receives and stores user programs and data according to the functions given by the PLC system program, collects the status or data sent by the on-site input device in the way of scanning, and stores them in the specified registers. At the same time, it diagnoses the working status of the power supply and the internal circuit of PLC and the syntax errors in the programming process. After entering the operation, read the instructions from the user program memory one by one. After analysis, generate corresponding control signals according to the tasks specified in the instructions to command the relevant control circuits.
CPU is mainly composed of arithmetic unit, controller, register and data, control and status lines to realize the connection between them. CPU unit also includes external chip, line interface and related circuits. Memory is mainly used to store programs and data, and is an indispensable component unit of PLC.
In the view of the user, it is not necessary to analyze the internal circuit of the CPU in detail, but there should be enough understanding of the working mechanism of each part. The CPU controller controls the CPU to work, and it reads, interprets and executes instructions. But t. rhythm is controlled by oscillation signal The arithmetic unit is used for digital or logical operation and works under the command of the controller. The register participates in the operation and stores the intermediate results of the operation. It also works under the command of the controller.