【正文】 If fuse oxygen Gao while set upper limit, the frequency modulation breeze machine turns to soon lower 5%.So, carried out Pu spirit pond to provide automatically regulate of the amount of oxygen, since avoided unnecessary energy loss, again excellent turned movement craft. 2. 2 The design of PLC program The adoptive plait distance software is a Concept 2. 2 is according to under the Windows of the PLC plait distance tool, have good customer39。 譯文： Application of control system on the base of PLC in sewage treatment The paper introduces a distributed control system of sewage treatment, and the core of the system is PLC. The structure of the control system, the assignment and implementation of the tasks, the control scheme and the design concept of program are expounded. The way of central monitoring management and dispersing control is used by the control system。 隨著自動(dòng)控制技術(shù)的發(fā)展， UNITANK 工藝越來(lái)越得到廣泛應(yīng)用。 （ 4）通信模塊 —— 用來(lái)完成 PLC 與上位機(jī)的各種數(shù)據(jù)傳送。若溶解氧低于設(shè)定下限時(shí)，調(diào)頻風(fēng)機(jī)轉(zhuǎn)速增加 5 % ；若溶解氧高于設(shè)定上限時(shí)，調(diào)頻風(fēng)機(jī)轉(zhuǎn)速降低 5 %.這樣，就實(shí)現(xiàn)了曝氣池供氧量的自動(dòng) 調(diào)節(jié)，既避免了不必要的能源損失，又優(yōu)化了運(yùn)行工藝。在這種方式下，所有各類設(shè)備都由 PLC 按照預(yù)先編制的程序自動(dòng)控制，不需要操作人員干預(yù) .各種現(xiàn)場(chǎng)數(shù)據(jù)通過(guò) PLC 傳至上位機(jī)，在上位機(jī)上描繪出來(lái)，使全廠的工藝、設(shè)備運(yùn)行得到全面的控制。 施耐德公司的 Modicon Quantum 系列 PLC 為滿足開(kāi)放的、基于標(biāo)準(zhǔn)的網(wǎng)絡(luò)連接和現(xiàn)場(chǎng)總線連接等應(yīng)用技術(shù)提供了多種網(wǎng)絡(luò)選擇，支持 Modbus,Modbus Plus（ MB+），遠(yuǎn)程 I/0, TCP/IP 等網(wǎng)絡(luò)連接，具有較強(qiáng)的靈活性。監(jiān)控界而包括系統(tǒng)總圖、系統(tǒng)分圖、模擬量一覽表、參數(shù)設(shè)置、報(bào)警窗、歷史趨勢(shì)、登錄窗等界而 .在系統(tǒng)總圖里，運(yùn)行人員能夠監(jiān)視所有控制設(shè)備的運(yùn)行狀態(tài)、設(shè)備事故及液位、流量等信號(hào) .在系統(tǒng)分圖里，操作人員能夠?qū)λ锌刂圃O(shè)備進(jìn)行單機(jī)點(diǎn)動(dòng)運(yùn)行操作、成組自動(dòng)運(yùn)行操作或全廠全自動(dòng)操作并監(jiān)視。具有結(jié)構(gòu)簡(jiǎn)單、性能優(yōu)越、可靠性高、靈話通用、易于編程、使用方便等優(yōu)點(diǎn)等。具體敘述了控制系統(tǒng)的結(jié)構(gòu)、任務(wù)分配及實(shí)現(xiàn)、控制方式和程序設(shè)計(jì)思想 .控制系統(tǒng)采用集中監(jiān)測(cè)管理、分散控制的方式，上位機(jī)負(fù)責(zé)現(xiàn)場(chǎng)設(shè)備的遠(yuǎn)程控制和監(jiān)視，軟件采用 Intouch7. 0 編制。國(guó)內(nèi)外許多污水處理廠采用了現(xiàn)代先進(jìn)控制技術(shù)和計(jì)算機(jī)技術(shù)，從而構(gòu)成計(jì)算機(jī)監(jiān)督、控制、管理系統(tǒng) .使系統(tǒng)優(yōu)化運(yùn)行。同時(shí)，也使得控制危險(xiǎn)分散，提高系統(tǒng)可靠性。 PLC3 本地控制站控制 SBR 生物處理部分 .另外，在現(xiàn)場(chǎng)本地控制站各設(shè) 1 臺(tái)操作終端設(shè)各，負(fù)責(zé)在本地對(duì)現(xiàn)場(chǎng)設(shè)各的控制 (自動(dòng)控制、點(diǎn)動(dòng)控制 )。 PLC 的 CPU 模塊通過(guò) MB+通信口與兩臺(tái)上位機(jī)進(jìn)行 數(shù)據(jù)交換，采集上位監(jiān)控系統(tǒng)的各種操作指令及現(xiàn)場(chǎng)檢測(cè)信號(hào)和數(shù)據(jù)，經(jīng)過(guò)分析處理，通過(guò)輸出模塊向控制對(duì)象輸出控制信號(hào)；同時(shí)，PLC 通過(guò) MB+網(wǎng)向上位機(jī)返回各種數(shù)據(jù)，上位機(jī)對(duì)數(shù)據(jù)進(jìn)行運(yùn)算處理，顯示各種信號(hào)和打印各種報(bào)表。根據(jù) SBR工藝要求，曝氣池內(nèi)的溶解氧含量通 ?？刂圃?1～ 3 mg/L 范圍內(nèi)，在曝氣階段末溶解氧含量應(yīng)不超過(guò) 2 mg/，均會(huì)影響出水質(zhì)量。 （ 2）開(kāi)關(guān)量順序控制模塊 —— 協(xié)調(diào)控制各個(gè)閥、泵、風(fēng)機(jī)等設(shè)備的運(yùn)行及相關(guān)故障的報(bào)警。 在曝氣的整個(gè)周期內(nèi)，隨時(shí)監(jiān)控變頻器的輸出電流值，使其不超過(guò)變頻器的額定值。在污水處理中，基于 PLC的控制系統(tǒng)在實(shí)時(shí) 性、可靠性、精確性等力一而滿足了設(shè)計(jì)要求，保證了污水處理的順利進(jìn)行。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 organization by the 4~20 mA electric current form after being output by the PLC, control performance organization 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 native PLC of room to pass MB+the work link PLC CPU mold piece passes MB+correspondence and two machines carry on data mutation and collect the place of honor supervision various operation instruction of th