IEC Basic Electrical Standards 4

Question 1

What does the term 'ampacity' mean as defined in the NEC?

Accepted Answer

The current in amperes a conductor can carry continuously under conditions of use

Answer

NEC Article 100 defines ampacity as the maximum current a conductor can carry continuously without exceeding its temperature rating.

Question 2

In a commercial building, where must GFCI protection be provided for 15- and 20-ampere, 125-volt receptacles per the NEC?

Accepted Answer

In all outdoor locations, restrooms, and within 6 feet of sinks

Answer

NEC 210.8(B) requires GFCI protection in commercial restrooms, outdoors, and within 6 feet of sinks, among other locations.

Question 3

When applying the 80% continuous load rule, how is the required ampacity of a branch circuit conductor calculated?

Accepted Answer

Non-continuous load + (continuous load × 1.25)

Answer

NEC 210.19 requires conductors to be sized at 125% of continuous loads plus 100% of non-continuous loads.

Question 4

What is the minimum size copper conductor required for a branch circuit serving a single 240-volt, 30-ampere receptacle?

Accepted Answer

10 AWG

Answer

A 30-ampere circuit requires 10 AWG copper conductors as specified in NEC Table 310.12.

Question 5

Under the NEC, a 'qualified person' is defined as one who has:

Accepted Answer

Skills and knowledge related to the construction and operation of electrical equipment

Answer

NEC Article 100 defines a qualified person as having the skills and knowledge related to electrical equipment construction and operation.

IEC - Independent Electrical Contractors Practice Test