Lesson 2: How Building Wire is Sized

Question 1

The ? of a conductor is defined as the diameter of the conductor in mils, squared.

Answer 1

circular-mil area

Question 2

To find the area of a wire in circular mils, square the diameter expressed in ?.

Answer 2

mils

Question 3

Which formula is used to find circular mil area?

Answer 3

Acmils = dmils2

Question 4

Which formula determines the resistance of a conductor?

Answer 4

Rohms = K × Lfeet / ACM

Question 5

In reference to wire size, AWG stands for American Wire Gauge.

Answer 5

True

Question 6

Write out in words what 250 kcmil means.

Answer 6

two hundred and fifty thousand circular mils

Question 7

To find the approximate resistance of a given copper conductor, drop the ? digit from the circular mil area. The result is the number of ? per ohm.

Answer 7

last / feet

Question 8

In general, all conductors ? AWG and larger, installed in a raceway, shall be stranded.

Answer 8

8; 310.106 (c)

Question 9

How many strands of 10 AWG wire would it take to make a 500-kcmil cable?

Answer 9

49

Question 10

The largest size wire listed in wire gauge number is ?.

Answer 10

4/0

Question 11

In general, the smallest size conductor permitted for 600 V is ? AWG copper or ? AWG aluminum or copper-clad aluminum.

Answer 11

14 / 12; 310.106 (a)

Question 12

There are no color coding requirements for grounded conductors found in the NEC.

Answer 12

False, 200.6

Question 13

What might happen to thermoplastic insulation at temperatures colder than -10°C (+14°F)?

Answer 13

the insulation might stiffen; 310.104

Question 14

The allowable ampacities in Table 310.15(B)(16) and Table 310.15(B)(17) are based on an ambient temperature of ?°F.

Answer 14

86