EETC Wiring & Installation Techniques 3

Question 1

When installing a ceiling fan, the electrical box must be rated for:

Accepted Answer

Fan support with the weight listed on the box

Answer

NEC 314.27(C) requires ceiling fan outlet boxes to be listed specifically for fan support, rated for the fan's weight.

Question 2

The color code for a 3-phase, 480-volt system's high-leg (wild leg) conductor is:

Accepted Answer

Orange

Answer

NEC 230.56 requires the high-leg (wild leg) of a 4-wire delta system to be identified with orange color.

Question 3

When using staples to secure NM cable, what is the maximum interval between staples in a vertical run?

Accepted Answer

4.5 feet

Answer

NEC 334.30 requires NM cable to be supported and secured at intervals not exceeding 4.5 feet (54 inches) along vertical runs.

Question 4

In a 3-wire, 240/120V single-phase system, if one hot leg fails, what happens to 120V loads on the remaining leg?

Accepted Answer

They operate normally at 120V

Answer

In a 3-wire system, each 120V load is connected between one hot leg and neutral, so loads on the intact leg continue to operate normally.

Question 5

What is the minimum cover required for a raceway installed under a concrete slab with no vehicular traffic?

Accepted Answer

0 inches — no cover needed

Answer

NEC Table 300.5 permits raceways installed under a concrete slab to have zero additional cover since the slab itself provides protection.

(EETC) Electrical Technician Certification Practice Test