Branch Circuits & WiringQuestion 218 of 521
A 12-2 Type NM cable (two 12 AWG conductors plus ground) is used for a general branch circuit. Using the required NM temperature column, what is the ampacity of its 12 AWG conductors?
a.25 A
b.20 A
c.30 A
d.15 A
Explanation
NM ampacity uses the 60°C column, where 12 AWG copper is 20 A. 25 A is the 75°C value and 30 A is the 90°C value, neither of which applies as the base for NM; 15 A is the 14 AWG (60°C) value.
Law Reference: 2023 NEC §334.80Practice all 521 questions free — no signup required.
Related questions on this topic
- Per Table 310.16, what is the ampacity of a 6 AWG copper conductor in the 75°C column?
- Per 334.80, the ampacity of Type NM (nonmetallic-sheathed) cable is based on which temperature column of Table 310.16?
- For Type NM cable, the 90°C rating of its conductors may be used for what purpose?
- Per 334.30, Type NM cable must be secured and supported at intervals not exceeding what distance along the run?
- Per 334.12, which of the following installations is NOT permitted for Type NM cable?
- Per 330.30, Type MC cable must be supported and secured at intervals not exceeding what distance?
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