NEW MEXICO LOW VOLTAGE
JOURNEYMAN ES3J STUDY GUIDE |
TESTBANK | PRACTICE QUESTIONS &
ANSWERS | CERTIFICATION EXAM
PREPARATION | ADVANCED REVIEW |
LATEST UPDATE 2026/2027 |
COMPREHENSIVE PRACTICE EXAM
SECTION 1: GENERAL REQUIREMENTS & LICENSE SCOPE
(Questions 1-25)
Question 1
According to New Mexico state rules, what is the maximum voltage scope for an ES-3J
licensee?
A) 120V
B) 240V
C) 50V or less
D) 600V
Answer: C) 50V or less
Rationale: The ES-3J license in New Mexico specifically limits the scope to special systems
operating at 50 volts or less, emphasizing safety and specialization in low-voltage work .
,Question 2
What is the minimum clearance to the edge of a wood stud for a wire hole?
A) 1/2 inch
B) 3/4 inch
C) 1 1/4 inches
D) 2 inches
Answer: C) 1 1/4 inches
Rationale: NEC 300.4(A)(1) requires that holes drilled in wood studs maintain a minimum
1 1/4 inch clearance from the edge of the stud to protect conductors from damage by nails
or screws .
Question 3
The NEC classifies Continuous Load as equipment running at a maximum load of __
_____?
A) 2 hours
B) 3 hours or more
C) 4 hours
D) 1 hour
Answer: B) 3 hours or more
Rationale: NEC 100.1 defines a continuous load as one where the maximum current is
expected to continue for 3 hours or more .
,Question 4
What is the minimum head room of working space above service equipment,
switchboards, panel boards, or motor control centers?
A) 6 feet
B) 6.5 feet
C) 7 feet
D) 8 feet
Answer: B) 6.5 feet
Rationale: Working space headroom requirements ensure safe access for maintenance and
operation of electrical equipment .
Question 5
What is the minimum width of working space required for electrical equipment that is
48 inches wide?
A) 36 inches
B) 42 inches
C) 48 inches
D) 60 inches
Answer: C) 48 inches
Rationale: The working space width must be at least the width of the equipment or 30
inches, whichever is greater. For 48-inch equipment, the working space must be at least 48
inches wide .
, Question 6
What percentage of conduit fill is allowed with three conductors?
A) 30%
B) 40%
C) 50%
D) 60%
Answer: B) 40%
Rationale: For three or more conductors in a conduit, the maximum fill is 40% of the
conduit's cross-sectional area .
Question 7
According to the NEC, electrical equipment may NOT be mounted to concrete, cinder
block, or brick walls with which of the following?
A) Expansion anchors
B) Wooden plugs
C) Toggle bolts
D) Lead anchors
Answer: B) Wooden plugs
Rationale: Wooden plugs are not permitted as a mounting method for electrical
equipment on masonry surfaces due to fire and stability concerns .
JOURNEYMAN ES3J STUDY GUIDE |
TESTBANK | PRACTICE QUESTIONS &
ANSWERS | CERTIFICATION EXAM
PREPARATION | ADVANCED REVIEW |
LATEST UPDATE 2026/2027 |
COMPREHENSIVE PRACTICE EXAM
SECTION 1: GENERAL REQUIREMENTS & LICENSE SCOPE
(Questions 1-25)
Question 1
According to New Mexico state rules, what is the maximum voltage scope for an ES-3J
licensee?
A) 120V
B) 240V
C) 50V or less
D) 600V
Answer: C) 50V or less
Rationale: The ES-3J license in New Mexico specifically limits the scope to special systems
operating at 50 volts or less, emphasizing safety and specialization in low-voltage work .
,Question 2
What is the minimum clearance to the edge of a wood stud for a wire hole?
A) 1/2 inch
B) 3/4 inch
C) 1 1/4 inches
D) 2 inches
Answer: C) 1 1/4 inches
Rationale: NEC 300.4(A)(1) requires that holes drilled in wood studs maintain a minimum
1 1/4 inch clearance from the edge of the stud to protect conductors from damage by nails
or screws .
Question 3
The NEC classifies Continuous Load as equipment running at a maximum load of __
_____?
A) 2 hours
B) 3 hours or more
C) 4 hours
D) 1 hour
Answer: B) 3 hours or more
Rationale: NEC 100.1 defines a continuous load as one where the maximum current is
expected to continue for 3 hours or more .
,Question 4
What is the minimum head room of working space above service equipment,
switchboards, panel boards, or motor control centers?
A) 6 feet
B) 6.5 feet
C) 7 feet
D) 8 feet
Answer: B) 6.5 feet
Rationale: Working space headroom requirements ensure safe access for maintenance and
operation of electrical equipment .
Question 5
What is the minimum width of working space required for electrical equipment that is
48 inches wide?
A) 36 inches
B) 42 inches
C) 48 inches
D) 60 inches
Answer: C) 48 inches
Rationale: The working space width must be at least the width of the equipment or 30
inches, whichever is greater. For 48-inch equipment, the working space must be at least 48
inches wide .
, Question 6
What percentage of conduit fill is allowed with three conductors?
A) 30%
B) 40%
C) 50%
D) 60%
Answer: B) 40%
Rationale: For three or more conductors in a conduit, the maximum fill is 40% of the
conduit's cross-sectional area .
Question 7
According to the NEC, electrical equipment may NOT be mounted to concrete, cinder
block, or brick walls with which of the following?
A) Expansion anchors
B) Wooden plugs
C) Toggle bolts
D) Lead anchors
Answer: B) Wooden plugs
Rationale: Wooden plugs are not permitted as a mounting method for electrical
equipment on masonry surfaces due to fire and stability concerns .
