Regarding the current-carrying capacity of copper bars, I would appreciate advice from experts in this field
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There has always been a question: if there is a copper bar that is 20 mm wide and 3 mm thick, and an 8 mm circular hole is made in it in order to fix it to an insulator. Will this situation affect the current-carrying capacity of the copper busbars? What is the current-carrying capacity of the copper bar at this time? Why, give the reason
There is definitely an impact, but it’s minimal. Why: The current-carrying capacity of a copper bar depends on the resistance from its starting point to its ending point. The copper bar can be considered as being composed of numerous small resistances connected in series; when holes are made in it, the resistance at those locations certainly increases. However, for the entire copper bar as a whole, this increase may be negligible. That’s how I understand it; I’m not sure if it’s correct. Because in the industry, the loss caused by the number of holes drilled in the copper bars is usually not taken into account.
If the copper bar is approaching its maximum current-carrying capacity, the area that first turns red and heats up must be the spot where holes have been made. In other words, drilling affects the maximum current-carrying capacity of the copper busbars; I’m not sure if this understanding is correct
This post was last edited by h20090630 on 2020-5-20 22:27. It certainly affects the current-carrying capacity; there’s no doubt about that. The current-carrying capacity of a copper bar is determined by its cross-sectional area. I recommend that you refer to the (copper bar technical specifications), which outline the requirements regarding hole placement, size, overlapping, bending, etc. Choose a design that meets your needs and follow the specifications; inspections should also be conducted in accordance with these specs, as no one else can provide any guidance on this matter. One must calculate that the results will vary depending on parameters such as the selected current, temperature, and whether it is enclosed or not. I intended to upload this (copper bar technical specification), but after trying for a long time I was unable to do so; I am very sorry about that.
This post was last edited by h20090630 on 2020-5-22 at 11:28. A search on Baidu for \"copper bar technical specifications\" yields many articles; I used the specifications from Huaneng, as the cabinets are meant for use in Huaneng power plants.