I know the NEC prohibits THHN for open wiring, requiring NM or UF instead. THHN must only be run in conduit or raceway.
But when my brother-in-law asked for the rationale behind this, I realized I had never contemplated such.
Anyone know the reasoning behind the rule?
But when my brother-in-law asked for the rationale behind this, I realized I had never contemplated such.
Anyone know the reasoning behind the rule?