Forums » Electrical Engineering

busbar short circuit

    • 3 posts
    August 23, 2019 11:05 AM PDT

     we have a bus with a 3-phase symmetrical momemntray short circuit of 50 kA, how can we calculate the busbar short circuit withstand capability. Any IEEE references?

    • 103 posts
    August 23, 2019 4:50 PM PDT

    My search of the IEEE library did not result in any papers on this topic.

    If the bus bar ampacity is based on 1000 amps per square inch the bar is good for 63ka.  The problem is with the support system.  The insulators supporting the copper will fail due to the mechanical stress exerted by the magnetic fields acting on the copper bars during the fault.

    Our new designs are based on the old designs, then a prototype is built & tested.

    To calculate you would have to determine the forces acting on the bars then see if the insulators have enough sheer & tensile strength to withstand those forces.  

    Consult the company that built the bus for ratings ?

    This post was edited by Steve Ward at August 23, 2019 4:56 PM PDT