With the 2014 NEC, the rules for feeder identification [215.12] are greatly expanded. That’s because the 2014 NEC adds rules for ungrounded feeder conductors supplied by DC systems [215.12(C)(2)].
Petrochemical plants have many thousands of feet of electric heat tracing. It’s used primarily for winterization or process heating. Winterization protection protects lines and vessels from freezing ...