CMI Electrical Systems Inspection 2

Question 1

Why do home inspectors flag Federal Pacific Electric (FPE) Stab-Lok panels during inspections?

Accepted Answer

Their breakers have been documented to fail to trip under overload conditions, creating a fire risk

Answer

FPE Stab-Lok breakers have been documented to fail to trip when overloaded, leaving circuits unprotected and posing a significant fire hazard.

Question 2

What is the primary inspection concern when 15-amp branch circuits in a home are wired with single-strand aluminum instead of copper?

Accepted Answer

Aluminum connections can loosen over time and overheat at devices and terminations not listed for aluminum conductors

Answer

Aluminum expands and contracts more than copper with temperature changes, causing connections to loosen at terminals not rated for aluminum, leading to overheating and fire risk.

Question 3

When inspecting the service entrance cable at the exterior of a home, which combination of items should the inspector evaluate?

Accepted Answer

Weatherhead height, drip loop presence, clearance from windows and doors, and proper sealing at the entry point

Answer

A complete service entrance inspection checks weatherhead height above grade, a drip loop to prevent water ingress, NEC-required clearances from openings, and a sealed penetration through the structure.

Question 4

A home inspector finds 14 AWG wiring (15-amp capacity) protected by a 30-amp circuit breaker. What deficiency is present?

Accepted Answer

Over-fusing: the breaker rating far exceeds the wire's safe ampacity, creating a fire hazard

Answer

Over-fusing occurs when overcurrent protection (the breaker) is rated higher than the wire it protects, allowing the wire to overheat and ignite before the breaker trips.

Question 5

Per NEC 110.26(A)(1), what minimum depth of clear working space is required in front of a residential electrical panel (0–150V to ground)?

Accepted Answer

36 inches

Answer

NEC 110.26(A)(1) requires at least 36 inches of clear working depth in front of electrical equipment operating at 0–150V to ground to allow safe access for electricians.

CMI - Certified Master Inspector Practice Test

CMI - Certified Master Inspector Practice Test

CMI Electrical Systems Inspection 2