E2 Plan Review and Inspections 2

Question 1

During a plan review for a commercial building, the inspector notices that the electrical drawings lack a fault current calculation. What should the inspector require before approving the plans?

Accepted Answer

Require the engineer to provide available fault current calculations and equipment interrupting ratings

Answer

Approve the plans and note the deficiency for field inspection

Answer

Accept the plans if the equipment is listed by a nationally recognized testing laboratory

Answer

Request only the load calculations since fault current is determined in the field

Question 2

A commercial plan set shows a 480V, 3-phase panel with a 400A main breaker but the service conductors are sized for only 350A. What is the correct inspector action?

Accepted Answer

Reject the plans and require conductors sized to at least 400A or a smaller main breaker

Answer

Approve the plans since the breaker protects the conductors

Answer

Allow the installation if conductors are in conduit rated for 90°C

Answer

Require the contractor to provide a written justification for the undersizing

Question 3

When reviewing plans for a commercial occupancy, which document is most important for verifying that proposed wiring methods are suitable for the environment?

Accepted Answer

The specification section listing approved wiring methods and environmental conditions

Answer

The project schedule submitted by the general contractor

Answer

The architectural reflected ceiling plan

Answer

The owner's equipment purchase orders

Question 4

A plan review reveals that a mechanical room will house a 480V motor control center (MCC). The plans do not show working space clearances. What should the inspector do?

Accepted Answer

Reject the plans and require dimensioned working space drawings per NEC 110.26

Answer

Approve the plans and verify clearances during the rough-in inspection

Answer

Accept the plans if the MCC is listed equipment

Answer

Allow the installation if the room is at least 10 ft × 10 ft

Question 5

During an inspection of a commercial building under construction, an inspector finds conduit installed in a concrete slab that is not listed for concrete encasement. What is the correct action?

Accepted Answer

Issue a correction notice and require removal and replacement with listed concrete-encased conduit

Answer

Allow the installation if the concrete will protect the conduit from physical damage

Answer

Approve the work if the contractor provides a written warranty

Answer

Accept the conduit if it meets the same trade size requirements

Question 6

A commercial electrical plan shows twelve 20A, 120V circuits in an office area. The inspector calculates the load exceeds the panel's available capacity. What action should be taken?

Accepted Answer

Reject the plans and require an amended load calculation and panel schedule showing adequate capacity

Answer

Approve the plans if the circuits will not all be used simultaneously

Answer

Allow the installation if a demand factor is applied by the contractor in the field

Answer

Accept the plans and note to verify load during final inspection

Question 7

When inspecting a commercial service entrance, the inspector observes that the service conductors pass through a basement ceiling space without conduit protection for approximately 8 feet. Which NEC requirement addresses this?

Accepted Answer

NEC 230.50, which requires service entrance conductors to be protected where subject to physical damage

Answer

NEC 300.11, which requires conduit to be supported at maximum 10-foot intervals

Answer

NEC 230.43, which lists permitted wiring methods for service entrance conductors above ground

Answer

NEC 110.14, which governs conductor terminations at service equipment