IS215VCMIH2CC
IS215VCMIH2CC
IS215VCMIH2CC
characteristics. In 1980, the Electrical Manufacturers Association of America (NEMA) gave him a new Programmable Controller, or PC. In 1982, the International Electrotechnical Commission (IEC) specifically for programmable controller under the strict definition. However, PC this abbreviation name has already become a synonym of Personal Computer (Personal Computer) in China, in order to avoid confusion of terminology, so the abbreviation name PLC is still used in China in the early stage of programmable controller, but this PLC does not mean only with logic function. 4. The definition of programmable controller Programmable controller has been under development, so until now, it has not been possible to give a final definition. The NEMA (National Electrical
Manufacturers Association) defined a programmable controller in 1980 as follows: “A programmable controller is a digital electronic device that uses programmable memory to store instructions for performing functions such as logic, sequence, timing, counting, and calculus, and for controlling various mechanical or production processes through digital or analog inputs and outputs. A digital electronic computer is regarded as a PLC if it is used to perform the functions of a PLC, but does not include a drum or mechanical sequential controller. The International Electrotechnical Commission (IEC) issued the first draft of the PLC standard in November 1982, the second in January 1985, and the third in February 1987. The definition of a programmable controller in the draft reads: “A programmable controller is an electronic system for numerical arithmetic operations, designed for applications in industrial environments. It uses programmable memory to store user-oriented instructions
such as logical operations, sequential control, timing, counting and arithmetic operations, and controls various types of machinery or production processes through digital or analog