第2个回答 2018-08-22
Apply with the development of PLC technology and their propulsion nowadays,PLC already becomes the system automation , informationize , long-range melt reach the intellectualized important pillar. As a result, studying PLC is integrated design of automatic system , an urgent demand of personnel being put into use and being maintained not only. The outcome may weave the program controller being that minitype computer art and relay routine control technique combine, is the new model controller sending out a felt on the sequential control basis getting up , is that a kind of is centering on microprocessor be used as digital control special use computer. Electromagnetism iron equipment except that the ironware is that in the nowadays large-scale factories , mines and enterprises middle is in common use, it applies to mine , dock , heat-engine plant , water , sugaring etc. broadly be not on magnetism material conveyer belt, be used to eliminate iron document in conveying up material , be protected a crusher thereby or be ground coal machine as well as safety improving the grade transporting material's. China energy Beijing heating and power plant conveys the quiet coal system 7 # belts central section two RCDB-14 type disk getting rid of an ironware , the anomaly adopt a logic to transport way alternately , controlling is complicated, since that whose control section still uses routine relay to control , the inside works a telephone switchboard is abnormal all over the place, relay quantity and kind gathering are also quite many , rates malfunction height , the job are as a result extremely not stable, charge if switching over to use PLC to be in progress to the person, whose stability will be of great rise. Be compared with routine relay under the control of , PLC is had weave Cheng Guan is nimble , easy modification of control logic, is under the control of powerful , the anti-interference ability is strong , reliability is advanced merit. As a result, PLC already has substituted routine's mainly in the automation field thinking that succeeding electric control , is applied broadly. Being superseded conveying the coal system disk with China energy Beijing heating and power plant getting rid of iron runs the main body of a book for the example , use MODICON685E type LC to realize whose alternately dyadic working function if the working condition except the ironware pursuing what 1 shows, the electric motor small reason on the handcart, drives two disks except that the ironware (be called CT1 , T2 for short) uses iron chain to hang going on foot on the crossbeam , can go on foot on the crossbeam, Spur on thereby going on foot except the implement in the primitive place , A belt place , B belt place cycle of 3 location (by the fact that 6 position-limit switch putting the crossbeam into fix position coming Q1 , SQ2 , SQ3 , SQ4 , SQ5 , SQ6).