These two winners each wrote a detailed violation notice letter, which stated that three copper strands were missing.
“The 500 MCM CU-THW conductor is missing three strands according to NEC Table 8 Conductor Properties. The picture in CEE News shows 34 strands, while Table 8 shows 37 strands required for 500 MCM CU. Table 310-16 shows an ampacity of 380A for 500 MCM-THW. The missing strands would result in a 92% decrease in amperage, thereby lowering the ampacity to 342A for the conductor shown.”
Bill MacMuson, Electrical Engineer
Exxon Mobil Res. And Engr.
Hal Jenkins, Electrical Engineer
Tennessee Valley Healthcare System