Core TradesQuestion 134 of 700
Under typical residential conditions, a copper 12 AWG conductor is generally protected at a MAXIMUM standard overcurrent rating of:
a.15 amperes
b.30 amperes
c.20 amperes
d.40 amperes
Explanation
Copper 12 AWG is protected at a maximum of 20 amperes under the standard small-conductor rules. 14 AWG copper is limited to 15 amperes and 10 AWG copper to 30 amperes. 40 amperes would badly overload a 12 AWG conductor and create a fire hazard.
Law Reference: 2025 CA Electrical Code, Art. 240.4 / Table 310.16Practice all 700 questions free — no signup required.
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