Zach Stone P.E.
Well-known member
Calculating the GMR and radius of transmission line bundle conductors is fast and easy, so why do most engineers get it wrong on the PE exam?
It's easy to confuse the variables in these formulas when working with more than one conductor per-phase (a bundle of conductors) since they look very similar but will result in different answers.
The variables used in these formulas in the NCEES Reference Handbook are also much different than the variables used in most power transmission line books which doesn't make it any easier.
Grab your calculator and follow along as I solve for both the geometric mean radius (GMR) and radius (r) for one, two, three, and four-conductor bundle configurations using real-world values.
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Live Class #1 is scheduled for Tuesday, July 6th, 2021.
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Have any questions on transmission line bundles? Reply to this comment and I'll do my best to answer.