Maximum distance for static grounding wire
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The static electricity grounding wires that lead away from the cable trays or equipment are connected to the grounding flat bars. How far can these wires be extended without affecting the effectiveness of grounding? Is there any relevant standard governing this? I would appreciate it if you could provide some guidance.
Ahah, regarding this marine enthusiast’s question about the distance between the static grounding points of the equipment, there are no specific regulations regarding that length; the main requirement is related to the cross-sectional area! However, it should be located in a place that is not easily affected by external forces, is easy to inspect and maintain, does not interfere with operations, and avoids areas where flammable mixtures are likely to accumulate or where rusting is likely to occur. As for the cable tray itself, its start and end points must be grounded ； To check whether the grounding meets the requirements, it is mainly determined by the value of the ground resistance. Typically, the ground resistance of an electrostatic grounding system should not exceed 1 megohm, while the ground resistance of a dedicated electrostatic grounding system should not be greater than 100 ohms ； In areas such as mountainous regions where the soil resistivity is high, the static grounding resistance should not exceed 1000 ohms.
SHT 3097-2017 Code for Design of Static Grounding in Petrochemical Industries; GB50169-2016 Code for Construction and Acceptance of Grounding Systems in Electrical Installation Projects
There is no requirement regarding distance; a resistance requirement exists, and generally, it is connected locally.