Distance between instrument cable trays and electrical cable trays
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May I ask what the distance should be between the instrument cable trays and the electrical cable trays? Is it determined according to the table in the specifications for laying chemical industry cables? Is it determined by the voltage and current transmitted by the power cable? The low-voltage distribution specifications state that the spacing between non-electric cables and electric cables should be 300 mm. According to the chemical industry standards, the laying distance between such cables in our project is around 300 meters; even with a current of 100 A, this distance exceeds 300 mm. I’m not sure what standard is generally used to determine this spacing
I’ve encountered similar problems too; this area is indeed tricky. To give you some personal opinions for reference: Prioritize the regulatory standards: Chemical industry regulations (such as SH/T 3012) specify clear spacing requirements for different voltage levels and signal types. For general low-voltage power cables (≤1kV) and non-power cables, a spacing of 300 mm is sufficient; however, in cases where the current is high or the distance is large, it is recommended to follow the spacing requirements for high-voltage systems (>1kV) or to use metal partitions. Special challenges of long-distance high-current applications: 300 meters of parallel wiring with a current of around 100A; in addition to electromagnetic interference, there are also risks related to heat dissipation and faulty arcs. In actual projects, I’ve seen designs where a length of over 500 mm is used, or metal shielding grooves are added in between, which makes it easier to pass the inspection. Ultimately, it depends on the design: different design firms will provide specific spacing tables or guidelines; it is advisable to consult with the design team first to avoid having to redo work later on. Additionally, the spacing requirements in the appendix of GB 50217-2018 can also be referred to; they are more detailed than those specified in the chemical industry standards. It’s always better to be cautious, after all, safety and interference are involved; it’s not a bad idea to leave some extra margin.
For that meter, the models that can handle 380V are only those with a current capacity of 100A or 200A; so how is the spacing determined for currents greater than 200A?
Just look at the voltage level; in electrical systems, it’s usually either 380V or 10KV. For high-voltage systems, the spacing is 1200mm, while for 380V systems it’s 600mm