NEW MEXICO ES-7 TELEPHONE COMMUNICATION SYSTEMS
EXAM COMPLETE EXAM QUESTIONS AND VERIFIED
ANSWERS | 2026–2027 LATEST UPDATE | GUARANTEED
PASS | DETAILED RATIONALES | FULL STUDY GUIDE | EXAM
PREP | PRACTICE TEST | CERTIFICATION PREPARATION
SECTION ONE — QUESTIONS 1–100
1. Which New Mexico state agency administers the ES-7 Telephone Communication Systems
licensing examination?
A) New Mexico Public Regulation Commission (NMPRC)
B) New Mexico Department of Workforce Solutions
C) New Mexico Construction Industries Division (CID)
D) New Mexico Energy, Minerals and Natural Resources Department
Correct Answer: C) New Mexico Construction Industries Division (CID)
Rationale: The New Mexico Construction Industries Division (CID), operating under the Regulation
and Licensing Department, is responsible for regulating all contractor licensing in the state, including
low-voltage electrical specialties such as the ES-7 Telephone Communication Systems classification .
The CID administers licensing requirements, approves testing vendors, and enforces compliance with
state regulations.
2. What is the primary code reference governing telephone and data communication circuits in
New Mexico?
A) NEC Article 725
B) NEC Article 760
C) NEC Article 800
D) NEC Article 300
Correct Answer: C) NEC Article 800
Rationale: NEC Article 800 specifically addresses communications circuits, including telephone, data,
and similar low-voltage systems . It establishes comprehensive requirements for installation,
grounding, protection, and wiring methods for telecommunications infrastructure. This article is the
foundational code reference for all ES-7 license holders.
3. Which edition of the National Electrical Code is currently enforced for the ES-7 examination in
New Mexico?
A) 2017 NEC
B) 2020 NEC
C) 2023 NEC
D) 2007 NEC
,Correct Answer: B) 2020 NEC
Rationale: New Mexico adopted the 2020 National Electrical Code, which became effective on March
28, 2023 . The ES-7 examination is based on this code edition, making it essential for candidates to be
thoroughly familiar with the 2020 NEC requirements. The NEC Handbook is an allowable reference in
the open-book exam.
4. A technician is running Category 6 cabling through a suspended ceiling that serves as an
environmental air plenum. What cable type is required by code?
A) CM-rated UTP cable
B) CMP-rated plenum cable
C) CMR-rated riser cable
D) CMX-rated residential cable
Correct Answer: B) CMP-rated plenum cable
Rationale: NEC Article 800.113(A) requires Type CMP (communications plenum cable) in ducts,
plenums, and other environmental air-handling spaces . Standard CM-rated cable emits toxic smoke
when burned, which would circulate through the HVAC system, creating a serious fire safety hazard.
5. What is the primary purpose of the demarcation point (DEMARC) in a telephone interconnect
system?
A) To amplify the incoming telephone signal for improved clarity
B) To serve as the legal boundary between the service provider's network and customer premises
wiring
C) To filter out line noise and improve voice quality
D) To house the battery backup for the telephone system
Correct Answer: B) To serve as the legal boundary between the service provider's network and
customer premises wiring
Rationale: The demarcation point, often a Network Interface Device (NID), is the legal and
operational boundary established by the FCC . It separates the regulated telephone network from the
customer's inside wiring and equipment, which is critical for troubleshooting and determining
responsibility for service issues.
6. According to the New Mexico ES-7J journeyman licensing requirements, how many hours of
verified experience are required?
A) 2,000 hours (1 year)
B) 4,000 hours (2 years)
C) 6,000 hours (3 years)
D) 8,000 hours (4 years)
Correct Answer: B) 4,000 hours (2 years)
Rationale: The New Mexico ES-7J Journeyman Telephone Communication Systems license requires
two years (4,000 hours) of verified experience in telecommunications work performed under a
licensed contractor . This experience must be properly documented and submitted with the license
application.
, 7. A technician measures 48 volts DC on a telephone line at the NID, but there is no dial tone at the
customer-side jack. Where is the fault likely located?
A) The central office switch is malfunctioning
B) The lightning arrestor is shorted
C) The inside customer premises wiring is shorted or open
D) The voltage is too low; it should be 90V
Correct Answer: C) The inside customer premises wiring is shorted or open
Rationale: Voltage present at the NID proves the service provider's network is functioning correctly .
Since the demarcation point is the boundary of responsibility, no dial tone on the customer side
indicates a fault in the customer premises wiring, not in the carrier's network.
8. What is the minimum size copper grounding electrode conductor required for a communications
system protector bond according to NEC Article 800?
A) 14 AWG
B) 10 AWG
C) 8 AWG
D) 6 AWG
Correct Answer: D) 6 AWG
Rationale: NEC Article 800.100(A)(4) requires the bonding conductor or grounding electrode
conductor for communications systems to be no smaller than 6 AWG copper . This minimum size
ensures a low-impedance path for fault currents, providing adequate protection against electrical
hazards.
9. When communications cables penetrate a fire-rated wall, what code requirement must be
followed?
A) No fire-stopping is required for low-voltage cables
B) An approved fire-stop system must be installed at each penetration
C) Only the top and bottom penetrations require fire-stopping
D) Standard silicone caulk is acceptable
Correct Answer: B) An approved fire-stop system must be installed at each penetration
Rationale: NEC 800.152 mandates approved fire-stop systems for communication cable penetrations
through fire-rated walls and floors . This requirement maintains the fire-resistance rating of the
assembly and prevents fire and smoke from spreading between compartments.
10. Which test instrument is most appropriate for locating the exact distance to a break or
impedance change in a copper telephone cable?
A) Tone generator and probe set
B) Digital multimeter
C) Time Domain Reflectometer (TDR)
D) Megohmmeter
Correct Answer: C) Time Domain Reflectometer (TDR)
EXAM COMPLETE EXAM QUESTIONS AND VERIFIED
ANSWERS | 2026–2027 LATEST UPDATE | GUARANTEED
PASS | DETAILED RATIONALES | FULL STUDY GUIDE | EXAM
PREP | PRACTICE TEST | CERTIFICATION PREPARATION
SECTION ONE — QUESTIONS 1–100
1. Which New Mexico state agency administers the ES-7 Telephone Communication Systems
licensing examination?
A) New Mexico Public Regulation Commission (NMPRC)
B) New Mexico Department of Workforce Solutions
C) New Mexico Construction Industries Division (CID)
D) New Mexico Energy, Minerals and Natural Resources Department
Correct Answer: C) New Mexico Construction Industries Division (CID)
Rationale: The New Mexico Construction Industries Division (CID), operating under the Regulation
and Licensing Department, is responsible for regulating all contractor licensing in the state, including
low-voltage electrical specialties such as the ES-7 Telephone Communication Systems classification .
The CID administers licensing requirements, approves testing vendors, and enforces compliance with
state regulations.
2. What is the primary code reference governing telephone and data communication circuits in
New Mexico?
A) NEC Article 725
B) NEC Article 760
C) NEC Article 800
D) NEC Article 300
Correct Answer: C) NEC Article 800
Rationale: NEC Article 800 specifically addresses communications circuits, including telephone, data,
and similar low-voltage systems . It establishes comprehensive requirements for installation,
grounding, protection, and wiring methods for telecommunications infrastructure. This article is the
foundational code reference for all ES-7 license holders.
3. Which edition of the National Electrical Code is currently enforced for the ES-7 examination in
New Mexico?
A) 2017 NEC
B) 2020 NEC
C) 2023 NEC
D) 2007 NEC
,Correct Answer: B) 2020 NEC
Rationale: New Mexico adopted the 2020 National Electrical Code, which became effective on March
28, 2023 . The ES-7 examination is based on this code edition, making it essential for candidates to be
thoroughly familiar with the 2020 NEC requirements. The NEC Handbook is an allowable reference in
the open-book exam.
4. A technician is running Category 6 cabling through a suspended ceiling that serves as an
environmental air plenum. What cable type is required by code?
A) CM-rated UTP cable
B) CMP-rated plenum cable
C) CMR-rated riser cable
D) CMX-rated residential cable
Correct Answer: B) CMP-rated plenum cable
Rationale: NEC Article 800.113(A) requires Type CMP (communications plenum cable) in ducts,
plenums, and other environmental air-handling spaces . Standard CM-rated cable emits toxic smoke
when burned, which would circulate through the HVAC system, creating a serious fire safety hazard.
5. What is the primary purpose of the demarcation point (DEMARC) in a telephone interconnect
system?
A) To amplify the incoming telephone signal for improved clarity
B) To serve as the legal boundary between the service provider's network and customer premises
wiring
C) To filter out line noise and improve voice quality
D) To house the battery backup for the telephone system
Correct Answer: B) To serve as the legal boundary between the service provider's network and
customer premises wiring
Rationale: The demarcation point, often a Network Interface Device (NID), is the legal and
operational boundary established by the FCC . It separates the regulated telephone network from the
customer's inside wiring and equipment, which is critical for troubleshooting and determining
responsibility for service issues.
6. According to the New Mexico ES-7J journeyman licensing requirements, how many hours of
verified experience are required?
A) 2,000 hours (1 year)
B) 4,000 hours (2 years)
C) 6,000 hours (3 years)
D) 8,000 hours (4 years)
Correct Answer: B) 4,000 hours (2 years)
Rationale: The New Mexico ES-7J Journeyman Telephone Communication Systems license requires
two years (4,000 hours) of verified experience in telecommunications work performed under a
licensed contractor . This experience must be properly documented and submitted with the license
application.
, 7. A technician measures 48 volts DC on a telephone line at the NID, but there is no dial tone at the
customer-side jack. Where is the fault likely located?
A) The central office switch is malfunctioning
B) The lightning arrestor is shorted
C) The inside customer premises wiring is shorted or open
D) The voltage is too low; it should be 90V
Correct Answer: C) The inside customer premises wiring is shorted or open
Rationale: Voltage present at the NID proves the service provider's network is functioning correctly .
Since the demarcation point is the boundary of responsibility, no dial tone on the customer side
indicates a fault in the customer premises wiring, not in the carrier's network.
8. What is the minimum size copper grounding electrode conductor required for a communications
system protector bond according to NEC Article 800?
A) 14 AWG
B) 10 AWG
C) 8 AWG
D) 6 AWG
Correct Answer: D) 6 AWG
Rationale: NEC Article 800.100(A)(4) requires the bonding conductor or grounding electrode
conductor for communications systems to be no smaller than 6 AWG copper . This minimum size
ensures a low-impedance path for fault currents, providing adequate protection against electrical
hazards.
9. When communications cables penetrate a fire-rated wall, what code requirement must be
followed?
A) No fire-stopping is required for low-voltage cables
B) An approved fire-stop system must be installed at each penetration
C) Only the top and bottom penetrations require fire-stopping
D) Standard silicone caulk is acceptable
Correct Answer: B) An approved fire-stop system must be installed at each penetration
Rationale: NEC 800.152 mandates approved fire-stop systems for communication cable penetrations
through fire-rated walls and floors . This requirement maintains the fire-resistance rating of the
assembly and prevents fire and smoke from spreading between compartments.
10. Which test instrument is most appropriate for locating the exact distance to a break or
impedance change in a copper telephone cable?
A) Tone generator and probe set
B) Digital multimeter
C) Time Domain Reflectometer (TDR)
D) Megohmmeter
Correct Answer: C) Time Domain Reflectometer (TDR)
