Grounding – Interpret the diagram!
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As shown in the figure: Is it necessary to use a wire conduit for this jumper? Is it standardized? Thank you for guiding the discussion. Thank you
According to the provisions on the grounding design of instrument systems in HG/T 20513-2014, Clause 5.1.1 specifies clearly:
It is necessary and complies with the standards. In fact, in cases where the support is grounded (such as on a pipe rack), it is possible to use wire ducts without jumpers (the metal tube is secured to the support with clamps, and the support is grounded). In your case, you can use 30MM flat steel to weld together the metal brackets under the pipes, which will yield better results.
I wonder if anyone here does this in person? Also, will doing this (using a clamp to fasten directly to the outside of the galvanized pipe) work? Did experts go to the site to check whether there were any items listed for rectification?
Personally, I think it’s meaningless; it’s done merely for the sake of appearing connected to reality, it’s a showpiece project. We need to understand what the purpose of grounding is: to eliminate static electricity. In fact, the metal wire conduits are already connected to each other, and the connection resistance between them is very low. The specifications require that the static grounding resistance between the protection pipes be no greater than 10 ohms. The connection between the protective tubes should be able to meet this requirement.
Refer to SH_T 3081-2019 Code for Design of Grounding of Instrumentation in Petrochemical Industries, sections 4.1.7 and 4.1.9
Could you please send a standard picture of the wiring job site? We’d like to use it as a reference for learning. Thank you.