IEC - Independent Electrical Contractors Special Occupancies and Equipment Questions and Answers

Question 1

An electrician is installing wiring for a branch circuit in a patient care space of a hospital. According to NEC Article 517, which of the following wiring methods is required to ensure a redundant grounding path?

Accepted Answer

Metal-clad (Type MC) cable with a metallic sheath that qualifies as an equipment grounding conductor and an insulated copper equipment grounding conductor.

Answer

NEC 517.13 requires branch circuits serving patient care spaces to be installed in a metal raceway or a cable with a metallic sheath that provides an effective ground-fault current path. Additionally, an insulated copper equipment grounding conductor must be installed with the branch circuit conductors. This creates two separate equipment grounding paths for enhanced safety.

Question 2

When installing a 125-volt, single-phase, 20-ampere receptacle near a permanently installed swimming pool, what is the minimum required horizontal distance from the inside walls of the pool?

Accepted Answer

6 feet

Answer

According to NEC 680.22(A)(3), receptacles that are not for pool equipment must be located at least 6 feet horizontally from the inside walls of the pool. Additionally, 680.22(A)(4) requires any 125-volt, 15- or 20-ampere receptacle located within 20 feet of the inside walls of the pool to be GFCI protected.

Question 3

In a commercial repair garage, the area up to 18 inches above the floor is classified as a Class I, Division 2 location. Which wiring method is permitted for fixed wiring installed ABOVE this classified location?

Accepted Answer

Electrical Metallic Tubing (EMT)

Answer

NEC 511.7(A)(1) permits several wiring methods for fixed wiring above Class I locations in commercial garages, including metal raceways like RMC, IMC, or EMT. Non-metallic sheathed cables like NM and UF are not permitted for this application.

Question 4

An equipotential plane is required in an agricultural building that houses livestock in a confinement area with a concrete floor. What is the minimum size solid copper bonding conductor required to connect this plane to the electrical grounding system?

Accepted Answer

8 AWG

Answer

NEC 547.10(B) (renumbered to 547.44(B) in some editions) mandates that the bonding conductor for an equipotential plane in an agricultural building shall be solid copper, insulated, covered, or bare, and not smaller than 8 AWG.

Question 5

At a marina, what is the maximum ground-fault protection (GFP) setting permitted for the main overcurrent device supplying a dock where shore power is provided to boats?

Accepted Answer

100 mA

Answer

NEC 555.35(A)(3) requires that feeder and branch-circuit conductors installed on docking facilities be provided with ground-fault protection of equipment (GFPE) set to open at currents not exceeding 100 mA. Receptacles providing shore power have a lower 30 mA requirement.

IEC - Independent Electrical Contractors Practice Test

IEC - Independent Electrical Contractors Practice Test

IEC - Independent Electrical Contractors Special Occupancies and Equipment Questions and Answers