Grounding methods for low-voltage distribution systems

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Let’s discuss the grounding methods in power distribution systems. The main types of grounding systems currently in use are TT, TN-C, TN-C-S, and TN-S. The TN-C system **has been explicitly prohibited from use, but several other methods are being employed to varying degrees. As for which one is the best, there are even differing opinions among **the various standards. The TT system is mainly used in rural areas with relatively dispersed power grids, while the TN-C-S and TN-S systems are primarily used in factories and enterprises that have their own transformers and dedicated electricians. However, the standards do not specify clearly the scope of application for TT and TN systems; as a result, different design firms adopt various grounding methods. I think that many of the “it is advisable to use” and “it is recommended to use” statements in the standards should be removed. Things should be clear-cut – one is one and two is two; the standards are too vague, and as a result, those involved in design will each have their own opinion. As for the TN-C-S system, it doesn’t sit well with me at all; it seems to be a transitional product similar to PHS – one that will eventually be phased out. It’s of an awkward design, and I strongly recommend that it be removed from the standards. To be honest, right now when I’m asked to design a grounding method, I really don’t know how to choose Any of them is too serious a crime to afford! Please help everyone.