NEW MEXICO EL-1J ELECTRICAL
DISTRIBUTION JOURNEYMAN EXAM
QUESTIONS AND ANSWERS
1. According to the NESC, what is the minimum vertical clearance for a 12.47 kV phase-to-
ground conductor over a road subject to truck traffic?
A. 15.5 feet
B. 20.0 feet
C. 18.5 feet
D. 22.5 feet
Answer: C
Conceptual Explanation: NESC Table 232-1 specifies 18.5 feet for voltages between 750V
and 22kV over roads subject to truck traffic.
2. What is the standard depth for setting a 40-foot utility pole in firm soil?
A. 4 feet
B. 5 feet
C. 6 feet
,D. 7 feet
Answer: C
Conceptual Explanation: The general rule for pole setting depth is 10% of the pole length
plus 2 feet. (40 * 0.10) + 2 = 6 feet.
3. Which transformer connection is most prone to ferroresonance in a distribution system?
A. Wye-Wye
B. Ungrounded Wye-Delta
C. Delta-Delta
D. Grounded Wye-Grounded Wye
Answer: B
Conceptual Explanation: Ungrounded primary connections, especially Wye-Delta
configurations, are highly susceptible to ferroresonance during single-phase switching.
4. Under NESC rules, what is the maximum resistance to ground for a single made electrode?
A. 5 Ohms
B. 10 Ohms
C. 50 Ohms
D. 25 Ohms
Answer: D
, Conceptual Explanation: NESC Rule 096B states that if the resistance exceeds 25 ohms, an
additional electrode must be used, though 25 ohms is the threshold for a single electrode.
5. What is the primary purpose of a ‘Creep’ calculation in overhead conductor installation?
A. To measure electrical resistance over time
B. To account for permanent elongation of the conductor under tension
C. To determine the leakage current of insulators
D. To calculate the swing of the conductor in high winds
Answer: B
Conceptual Explanation: Creep is the non-elastic, permanent stretch of a conductor that
occurs over time under tension, which affects final sag.
6. In a three-phase Delta system, if one phase-to-ground voltage is 0V, what does this
indicate?
A. A normal operating condition
B. A blown transformer fuse
C. An open neutral
D. A ground fault on that phase
Answer: D
Conceptual Explanation: In an ungrounded or corner-grounded Delta system, a 0V
reading to ground indicates that the specific phase is electrically connected to earth.
DISTRIBUTION JOURNEYMAN EXAM
QUESTIONS AND ANSWERS
1. According to the NESC, what is the minimum vertical clearance for a 12.47 kV phase-to-
ground conductor over a road subject to truck traffic?
A. 15.5 feet
B. 20.0 feet
C. 18.5 feet
D. 22.5 feet
Answer: C
Conceptual Explanation: NESC Table 232-1 specifies 18.5 feet for voltages between 750V
and 22kV over roads subject to truck traffic.
2. What is the standard depth for setting a 40-foot utility pole in firm soil?
A. 4 feet
B. 5 feet
C. 6 feet
,D. 7 feet
Answer: C
Conceptual Explanation: The general rule for pole setting depth is 10% of the pole length
plus 2 feet. (40 * 0.10) + 2 = 6 feet.
3. Which transformer connection is most prone to ferroresonance in a distribution system?
A. Wye-Wye
B. Ungrounded Wye-Delta
C. Delta-Delta
D. Grounded Wye-Grounded Wye
Answer: B
Conceptual Explanation: Ungrounded primary connections, especially Wye-Delta
configurations, are highly susceptible to ferroresonance during single-phase switching.
4. Under NESC rules, what is the maximum resistance to ground for a single made electrode?
A. 5 Ohms
B. 10 Ohms
C. 50 Ohms
D. 25 Ohms
Answer: D
, Conceptual Explanation: NESC Rule 096B states that if the resistance exceeds 25 ohms, an
additional electrode must be used, though 25 ohms is the threshold for a single electrode.
5. What is the primary purpose of a ‘Creep’ calculation in overhead conductor installation?
A. To measure electrical resistance over time
B. To account for permanent elongation of the conductor under tension
C. To determine the leakage current of insulators
D. To calculate the swing of the conductor in high winds
Answer: B
Conceptual Explanation: Creep is the non-elastic, permanent stretch of a conductor that
occurs over time under tension, which affects final sag.
6. In a three-phase Delta system, if one phase-to-ground voltage is 0V, what does this
indicate?
A. A normal operating condition
B. A blown transformer fuse
C. An open neutral
D. A ground fault on that phase
Answer: D
Conceptual Explanation: In an ungrounded or corner-grounded Delta system, a 0V
reading to ground indicates that the specific phase is electrically connected to earth.
