Core TradesQuestion 23 of 700
A 240-volt, 30-ampere dedicated circuit is wired with copper conductors. Under typical residential conditions, what is the MINIMUM copper conductor size that matches this 30-ampere circuit?
a.14 AWG
b.12 AWG
c.10 AWG
d.8 AWG
Explanation
A 30-ampere circuit is normally served by 10 AWG copper, which carries 30 amperes under standard conditions. 14 and 12 AWG are limited to 15 and 20 amperes, while 8 AWG is larger than necessary.
Law Reference: 2025 CA Electrical Code (CEC) Art. 240 (Overcurrent Protection)Practice all 700 questions free — no signup required.
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