过滤器反洗的自动控制具有许多优点，例如操作的一致性、节省时间和保存记录。本文简要介绍了为北德克萨斯州市政供水区设计的40台过滤器控制系统。采用可编程逻辑控制器对调节式液压驱动出水阀进行控制。该系统由八个PLC组成，每个PLC控制五个滤波器。第九个PLC提供监控和报警输出。PLC以两种方式连接，这样连接或任何单个PLC的故障都不会妨碍系统其余部分的正常运行。附加对电厂控制系统的简要说明。

Automatic control of filter backwashing has a number of advantages, such as consistency of operation, time savings, and record keeping. This paper briefly describes a system designed to control 40 filters for the North Texas Municipal Water District. A programmable logic controller was used to control the modulating hydraulic actuated effluent valves. The system consists of eight PLCs, each controlling five filters. A ninth PLC provides monitoring and alarm outputs. The PLCs were linked in two ways so that the failure of the linkage or any single PLC would not prevent the normal operation of the remainder of the system. A brief description of the plant's control system is appended.