Discontinued Spare 07KT97C Limited stock

Domestic PLC plant about 30, but did not form a large-scale production capacity and brand-name products, as well as partially in imitation, contract assembly or "OEM" mode of production, it can be said PLC is not formed in our manufacturing industry. As a principle, technology and workmanship difficulty of cutting-edge technology products, if they work hard, they are capable of forming manufacturing industries. PLC applications in our country is very active, every year about 100,000 sets of new investment PLC products, with annual sales of 3 billion yuan, industrial applications is very wide. However, compared with other countries in the machining and application aspects of the production line, but also need to increase investment. There are several popular PLC products on the Chinese market: (1) Schneider, including early introduction of Tianjin Instrument Factory Modicon company's products, there are Quantum, Premium, Momentum, and other products; (2) Rockwell ( including AB company) PLC products are currently SLC, Micro Logix, Control Logix and other products; (3) Siemens products, there are SIMATIC S7-400 / 300/200 series of products; (4) GE's products; Omron , Mitsubishi, Fuji, Panasonic and other products. PLC's market potential is enormous, not only in our country, even in the industrial development of Japan survey showed that the proportion of PLC supporting mechatronic products accounted for 42%, the use of relays, contactors, control still 24%. Therefore, the need to apply the PLC are still many occasions in our country even more so. From the perspective of technological innovation, China's large and medium sized enterprises should develop CIMS (Computer Integrated Manufacturing System), to be formed in a machinery factory FMS flexible manufacturing system, PLC is the foundation, so the PLC market is vast. PLC has a reliable, inexpensive, full-featured, application flexibility, easy operation and maintenance advantages, which is capable of enduring the root causes of market share, we have the following focuses on several issues, and to study its trends. 3.1 PLC hardware and software Classification PLC in the 1990s has been the formation of micro, small, medium, large, huge variety of PLC. Press the I / O points can be divided into: l Micro PLC: 32 I / O l Small PLC: 256 I / O l Medium PLC: 1024 I / O l Large PLC: 4096 I / O l giant PLC: 8195 I / O has a single large system support 300 loop and 65,000 I / O points above corresponds to medium-sized PLC, are used in 16 to 32 CPU, micro, small PLC original 8-bit CPU, according to communications requirements, etc., some also switch 16 - 32-bit CPU. Since the I / O64 points below sales accounted for 47% of the entire PLC PLC, and 64 points to 256 points or 31 per cent, totaling a 78% of the entire PLC sales, so the micro, small PLC should be more research. 3.2 PLC hardware PLC controller itself using the modular structure of the hardware, the manufacturers of the product structure similar. Japan's Omron C200HE example, a template for the bus frame structure, equipped with the basic framework (CPU motherboard) CPU template, other slots containing I / O modules; if the I / O modules for a long time, by the CPU via the motherboard I / O extension cable to connect I / O expansion backplane, tops in its I / O modules; the other way is with remote I / O from the station. All this shows that the PLC hardware manufacturers will have to develop the various components to the user, user-friendly selection, ranging from the size configured PLC, and this hardware configuration openness, for manufacturers, distributors (agents), systems integrators end users a lot of convenience, to bring great convenience for the marketing supply chain, which is a big success experience. I PLC inside / O modules, in addition to the general DI / DO, AD / DA template, has also developed a series of special features of I / O modules, which for the PLC used in various industries, opened new ways, such as for bar codes Recognition ASCII / BASIC templates, templates for PID feedback control for operational control, machining of high-speed counting template, single-axis position control module, dual-axis position control module, the cam locator template, RFID interface modules, etc. This will be a great development in the future. Also in the relevant component input, output, strong interference input and output electrical isolation, isolation and other aspects of the case will be more perfect. The PLC CPU and memory with complete control. It is with the DCS system processing temperature, pressure, flow and other system parameters are different, with quick tour scan, typically 0.1 ~ 0.2s, the faster the choice of 50ms or less sweep. It is a digital sampling control system. 3.3 PLC software for complete control strategy, in order to replace the relay, allowing users complete control system and other similar line relay ladder, and prepared a set of control algorithms function block (or subroutine) is called command system, cured in storage the ROM, the user can call in the preparation of the application. Instruction set can be divided into two categories, namely, the basic instructions and extended instructions. Subdivision general PLC command system are: basic instructions, timer / counter instruction, shift instructions, transfer instructions, compare instructions, conversion instructions, BCD arithmetic instructions, binary arithmetic instruction, increment / decrement instructions, logical operation instructions, special operations command, etc., these instructions are mostly similar to assembly language. In addition PLC also improves enough timers, counters, internal relays, registers and memory areas such as internal resources, a great convenience for programmers.