Question
Would you please help me in understanding NEC-2002 300.4(F)? If a 4 AWG or larger conductor is being installed in EMT with a insulated throated connector, would a insulated bushing be required? — R. F.
Answer
NEC-2002, Section 300.4(F) says: “…the conductors shall be protected by a substantial fitting providing a smoothly rounded insulating surface…” and does not specifically require a bushing. The bushing is only mentioned in the second paragraph in regard to a different requirement of 300.4(F)
The idea is to have an insulated surface contacting the conductor, and an insulated throat connector accomplishes this. — Richard Owen, CMP-3