Required contact area for electrical connection
Required contact area for electrical connection
(OP)
Looking for some sparky knowledge here. I'm designing some test equipment and need to make sure I have enough contact area to prevent heating a threaded connection beyond the point where it can be reused.
We will be running 1000V and 1000A through the connection. The real trick is the duration will only be for a few seconds. Should be around 3s but I would like to design for 6s just in case.
Anyone have any thoughts or good reference material? Keep in mind that I am a lowly ME starting out haven't expanded my electrical kowledge much yet. Also, is there a particular contact pressure I need to maintain? Thanks.
Brian
We will be running 1000V and 1000A through the connection. The real trick is the duration will only be for a few seconds. Should be around 3s but I would like to design for 6s just in case.
Anyone have any thoughts or good reference material? Keep in mind that I am a lowly ME starting out haven't expanded my electrical kowledge much yet. Also, is there a particular contact pressure I need to maintain? Thanks.
Brian





RE: Required contact area for electrical connection
Assuming that isn't applicable to your situation we need to know more about the design of the joint or coupling and the materials it is constructed from.
Some welding connectors use a twist-lock arrangement: the larger ones would probably withstand 1000A for 6 seconds. A word of warning: welder suppliers are very optimistic with their ratings.
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Sometimes I only open my mouth to swap feet...
RE: Required contact area for electrical connection
The copper of choice for this application is UNS c10200 H04. Based on the info I pulled off of copper.org the minimum yield strength of the material is 40-50ksi depending on the size rod used.
RE: Required contact area for electrical connection
respectfully
RE: Required contact area for electrical connection
www.copper.org
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Sometimes I only open my mouth to swap feet...
RE: Required contact area for electrical connection
RE: Required contact area for electrical connection
respectfully
RE: Required contact area for electrical connection
This will be held in compression either against another similar lug, or perhaps a copper busbar, brass block, or something similar.
Through this goes a bolt, stud or whatever. The most important feature of this is that the threaded fastner only supplies the clamping force to press and hold the actual copper current carrying parts of the system together.
The bolt absolutely MUST NOT CARRY ANY CURRENT ITSELF. It is only there to clamp and hold the current carrying parts together. If a lot of force is required, high tensile fine threaded steel bolts will be best, used with thick steel washers if necessary. The copper lug must be squashed flat and held rigid against whatever the current has to flow into.
The practiced eye of a mechanical engineer should be quite sufficient for sizing these clamping bolts. If it looks about right and in proportion, it probably is right.
RE: Required contact area for electrical connection
I will try to post results when I get them. What I did to minimize risk in our testing application is to maximize contact area to reduce the current density in the connection. Based on the available contact area, the current density should be less than a third of what it is elsewhere in the DC path.
Brian