【正文】 fuse oxygen low limit at the bottom of the enactment, the frequency modulation breeze machine turns to soon increase 5%。s name and password and then can carry out long range came to carried on a control to the equipments of whole the sewage data of wastewater treatment factory to the national environmental protection bureau through an Inter in the meantime city environmental protection bureau perhaps, for the purpose of the Bu class management of section to wastewater treatment factory. 。s interface, and have online follow and offline imitate true control procedure of PLC3 stationses is divided into five procedure mold piece. (1)Public mold pieces of procedure useinclude a beginning to start to turn part, hour cent second etc. ask pulse unit, SBR to respond a period enactment, fuse oxygen enactment...etc.. (2)Order control mold pieces of the switch quantity the coordination control report to the police of circulate and related breakdown of equipmentses, such as each valve, pump and breeze machine...etc.. The enter of SBR pond spirit valve, enter water valve, reflux pump, surplus dirty mire pump from PLC according to the craft of the wastewater treatment period time segment control, water valve from PLC according to craft time and super voice liquid the measured value of the instrument to control. (3)Protection mold pieces of the offpowersystem power failure after, the PLC saves all appearance locks and make after treating to add an electricity PLC instauration keep of the appearance continue to circulate. (4)Mold pieces of correspondences use to plete PLC and various data transmission of place of honor machine. (5)Fuse an oxygen value to automatically regulate a mold pieceaccording to fuse an oxygen value to regulate breeze machine to turn soon and report to the police of related target which regulates to turn soon promises the be worth of deliquescence oxygen as 2 mgs/L in the whole Pu spirit control strategy is as follows:The Pu spirit period beginning, the breeze machine at top speed movement attains a 2 mgs/L in shorterly of the hour ask by making deliquescence oxygen and take 5 mins as a period to examine deliquescence oxygen to be worth in the fuse an oxygen value big at the 2 mgs/L, the breeze machine turns to soon descend 5%。s etc. imitate quantity, from to in response to of an appearance spread a feeling machine or change to send to a machine examination to e out and change into the electric current signal of the 4~20 mA, through shield inside the PLC that the electric cable sends to each statures system, from the PLC picks up a people through various mold piece sample telemunication , imitate quantity control the signal send to performance anization by the 4~20 mA electric current form after being output by the PLC, control performance anization of action. The Modicon Quantum series PLC of Schneider pany is satisfy liberal of, according to standard of work conjunction and the spot total line conjunction etc. application the technique provided various work a choice, support Modbus, Modbus Plus(MB+), the long range I/0, TCP/IP etc. work conjunction, have stronger and , the wastewater treatment is convenient to arrive of the PLC choose the series of Modicon Ouantum of use Schneider. 1. 3 Correspondences MB+agreement is the Modicon pany release of an open type of the adoption IEEE802. 4 correspond by letter 5 agreements the spot total line of card +the work together other works pare to have a set of simple, the investment be little, work speed quick, correspondence the stability strong etc. characteristics, it make calculator, controller and other data sources through an usage double wring line or fiber optic cable Be a body to together carry on correspondence at the whole work the CPU mold piece of the Modicon Quantum series PLC imply MB+correspondence, therefore correspond by letter a work to choose to use MB+ control two machine, two control stations with nati