IOWA MASTER
ELECTRICIAN EXAM
QUESTIONS AND
VERIFIED ANSWERS
WITH RATIONALES
JUST RELEASED
EXAM SPECIFICATIONS
Time Allocation: 4 Hours
Total Questions: 100 Questions
Question Format: Multiple Choice with Calculations
Minimum Competency: 75% Required to Pass
Core Focus: NEC Code, Calculations, Motors, Grounding, Iowa Law
Iowa Master Electrician Exam Just Released Page 1
, Exam Overview & Content Outline
EXAM PURPOSE
Iowa Master Electrician Exam validates competency for unlimited electrical contracting per Iowa
Electrical Examining Board. Covers NEC 2023, calculations, motors, transformers, grounding, and
Iowa Administrative Code Chapter 661.
CONTENT DISTRIBUTION
• NEC Code & Theory (35%) — Articles 90-110, 210, 220, 250, 310, 430, 440, 450
• Calculations (30%) — Load calculations, conductor sizing, conduit fill, voltage drop, box fill
• Motors & Equipment (20%) — Article 430, motor circuits, overload protection, disconnects
• Iowa Law & Safety (15%) — Iowa Code Chapter 103A, IAC 661, licensing, OSHA, business
practices
QUESTION FORMAT & SCORING
Each item presents four options with NEC calculations. Correct answers are highlighted in green
with checkmark (✓). Every question includes detailed solution with NEC article citations. Requires
75% to pass.
STUDY STRATEGY
Master NEC 2023: Article 220 load calculations, Article 250 grounding, Article 310 ampacity, Article
430 motors. Know Iowa amendments. Practice calculations: dwelling unit loads, commercial loads,
motor circuits, transformer sizing, voltage drop. Study Iowa Code Chapter 103A and IAC 661
licensing requirements.
CURRICULUM ALIGNMENT
Questions reflect current standards: NEC 2023, Iowa Code Chapter 103A (State Building Code), IAC
661 (Electrical Examining Board), NFPA 70E, and OSHA 29 CFR 1926.
Iowa Master Electrician Exam Just Released Page 2
, SECTION I: NEC Code & Theory
1. NEC Article 250 covers:
A. Branch circuits
✓ B. Grounding and bonding
C. Motors
D. Lighting
Rationale: NEC Article 250: Grounding and Bonding. Covers: grounding electrode system, equipment
grounding conductors, bonding jumpers, ground fault protection. Key sections: 250.50 (electrodes), 250.66
(GEC sizing), 250.122 (EGC sizing). IA Master exam requires grounding calculations. Grounding electrodes
must be bonded together.
2. GFCI protection required for dwelling unit receptacles in:
A. Bedrooms only
✓ B. Bathrooms, kitchens, garages, outdoors, basements, laundry
C. Living rooms only
D. No GFCI required
Rationale: NEC 210.8(A): GFCI required for 125V-250V, 15A-20A receptacles in: bathrooms, garages,
outdoors, crawl spaces, basements, kitchens (countertops), sinks (within 6 ft), laundry areas. IA enforces
NEC 2023. AFCI required in bedrooms, living rooms per 210.12. Test monthly.
3. Service disconnecting means maximum number:
A. Unlimited
✓ B. Six switches or breakers
C. One only
D. Twelve
Rationale: NEC 230.71: Service disconnecting means shall consist of not more than six switches or sets of
circuit breakers. Single enclosure or separate enclosures grouped. 2020 NEC: One service disconnect
preferred, six-handle rule being phased out. IA still allows six disconnect rule. Must be readily accessible.
4. Conductor ampacity for 3/0 THHN copper in raceway:
A. 100A
✓ B. 200A at 75°C
C. 400A
D. 50A
Rationale: NEC Table 310.16: 3/0 THHN copper: 75°C column = 200A. 60°C = 165A, 90°C = 225A. Use
75°C column for terminations unless marked 90°C. IA Master must know ampacity table. Adjustment factors
for >3 CCC or ambient >30°C. THHN is 90°C rated but terminations limit to 75°C.
5. Equipment grounding conductor for 40A circuit:
A. #14 AWG
✓ B. #10 AWG copper
Iowa Master Electrician Exam Just Released Page 3
ELECTRICIAN EXAM
QUESTIONS AND
VERIFIED ANSWERS
WITH RATIONALES
JUST RELEASED
EXAM SPECIFICATIONS
Time Allocation: 4 Hours
Total Questions: 100 Questions
Question Format: Multiple Choice with Calculations
Minimum Competency: 75% Required to Pass
Core Focus: NEC Code, Calculations, Motors, Grounding, Iowa Law
Iowa Master Electrician Exam Just Released Page 1
, Exam Overview & Content Outline
EXAM PURPOSE
Iowa Master Electrician Exam validates competency for unlimited electrical contracting per Iowa
Electrical Examining Board. Covers NEC 2023, calculations, motors, transformers, grounding, and
Iowa Administrative Code Chapter 661.
CONTENT DISTRIBUTION
• NEC Code & Theory (35%) — Articles 90-110, 210, 220, 250, 310, 430, 440, 450
• Calculations (30%) — Load calculations, conductor sizing, conduit fill, voltage drop, box fill
• Motors & Equipment (20%) — Article 430, motor circuits, overload protection, disconnects
• Iowa Law & Safety (15%) — Iowa Code Chapter 103A, IAC 661, licensing, OSHA, business
practices
QUESTION FORMAT & SCORING
Each item presents four options with NEC calculations. Correct answers are highlighted in green
with checkmark (✓). Every question includes detailed solution with NEC article citations. Requires
75% to pass.
STUDY STRATEGY
Master NEC 2023: Article 220 load calculations, Article 250 grounding, Article 310 ampacity, Article
430 motors. Know Iowa amendments. Practice calculations: dwelling unit loads, commercial loads,
motor circuits, transformer sizing, voltage drop. Study Iowa Code Chapter 103A and IAC 661
licensing requirements.
CURRICULUM ALIGNMENT
Questions reflect current standards: NEC 2023, Iowa Code Chapter 103A (State Building Code), IAC
661 (Electrical Examining Board), NFPA 70E, and OSHA 29 CFR 1926.
Iowa Master Electrician Exam Just Released Page 2
, SECTION I: NEC Code & Theory
1. NEC Article 250 covers:
A. Branch circuits
✓ B. Grounding and bonding
C. Motors
D. Lighting
Rationale: NEC Article 250: Grounding and Bonding. Covers: grounding electrode system, equipment
grounding conductors, bonding jumpers, ground fault protection. Key sections: 250.50 (electrodes), 250.66
(GEC sizing), 250.122 (EGC sizing). IA Master exam requires grounding calculations. Grounding electrodes
must be bonded together.
2. GFCI protection required for dwelling unit receptacles in:
A. Bedrooms only
✓ B. Bathrooms, kitchens, garages, outdoors, basements, laundry
C. Living rooms only
D. No GFCI required
Rationale: NEC 210.8(A): GFCI required for 125V-250V, 15A-20A receptacles in: bathrooms, garages,
outdoors, crawl spaces, basements, kitchens (countertops), sinks (within 6 ft), laundry areas. IA enforces
NEC 2023. AFCI required in bedrooms, living rooms per 210.12. Test monthly.
3. Service disconnecting means maximum number:
A. Unlimited
✓ B. Six switches or breakers
C. One only
D. Twelve
Rationale: NEC 230.71: Service disconnecting means shall consist of not more than six switches or sets of
circuit breakers. Single enclosure or separate enclosures grouped. 2020 NEC: One service disconnect
preferred, six-handle rule being phased out. IA still allows six disconnect rule. Must be readily accessible.
4. Conductor ampacity for 3/0 THHN copper in raceway:
A. 100A
✓ B. 200A at 75°C
C. 400A
D. 50A
Rationale: NEC Table 310.16: 3/0 THHN copper: 75°C column = 200A. 60°C = 165A, 90°C = 225A. Use
75°C column for terminations unless marked 90°C. IA Master must know ampacity table. Adjustment factors
for >3 CCC or ambient >30°C. THHN is 90°C rated but terminations limit to 75°C.
5. Equipment grounding conductor for 40A circuit:
A. #14 AWG
✓ B. #10 AWG copper
Iowa Master Electrician Exam Just Released Page 3
