Core TradesQuestion 184 of 700
Ampacity derating (adjustment) for bundled conductors generally begins to apply once a raceway or cable contains MORE than how many current-carrying conductors?
a.Two
b.Three
c.Six
d.Nine
Explanation
Adjustment factors apply when more than three current-carrying conductors share a raceway or cable, because bundled conductors cannot shed heat as easily. Two or three conductors do not trigger derating, and waiting until six or nine would allow dangerous overheating.
Law Reference: 2025 CA Electrical Code, Article 310 (Conductor Ampacity)Practice all 700 questions free — no signup required.
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