DCS系统接地的探讨

水泥厂DCS系统所发送的信号有的不被干扰，有的被干扰得非常严重。产生干扰的原因很多，但接地问题是主要的原因之一。为TDCS系统的可靠运行，设计时必须考虑其接地问题。工厂中接地的种类主要有工作接地、保护接地、屏蔽接地、防静电接地和防雷接地等。除防雷接地外，其他接地一般可与电气接地网共地，但是要严格区分不同性质的地，做到不混接。不同性质的地用分干线接入各自的汇流板（或者直接接入总的汇流板），各汇流板用总干线接入公共接地极（网），在最终处汇入一点接地。

Discussion on DCS earthing

Some of the signals transmitted from DCS in cement plant are not interfered, but other signals are seriously interfered by various reasons. Nevertheless, one of the main reasons consists in earthing problems. For the reliable running of DCS, earthing devices should be considered in design. Main types of earthing in industrial plants include operational earthing, protective earthing, shielding earthing, electrostatic- proof earthing and lightning-proof earthing etc. Except lightning-proof earthing, other type of earthing system can be arranged together with electrical earthing net, in which different natures of earthing should be strictly distinguished and to avoid mixing earthing connection. Earthing system of different types can be connected to their respective bus plate by sub-major cables (or connected directly to general bus plate), and all the bus plates should be connected to public earthing pole (or net) by the major cable, and then gathered to one terminal point for final earthing.