NM ES-3 TEST (2025) EXAM
QUESTIONS AND ANSWERS
What is the minimum clearance to the edge of a wood stud for a wire hole? - ANSWER1
1/4 inches(NEC 300.4 A 1)
What is the minimum separation between a class 1 fire alarm circuit conductor and a
class 2 or class 3 circuit? - ANSWER1/4 inch
A basic alarm system will have __ power sources. - ANSWER2
What is the minimum required clearance between a receiving antenna and 250 volt line
not insulated? - ANSWER2 Feet
The minimum clearance for an antenna to other conductors is? - ANSWER2 Feet (NEC
810.13)
How far away must communications cables be from electric, light, or power conductors -
ANSWER2 inches
what is the maximum blink rate on a strobe light per second? - ANSWER2 (NFPA 72
18.5.2.1)
On a voice alarm system what is the minimum number of cycles it has to report an
evacuation procedure? - ANSWER2 (NFPA 72 24.4.1.2.1)
What is the minimum required height for a propriety manual pull fire alarm? - ANSWER3
1/2 feet or 42 inches
An overhead feeder must have a clearance of __ from chimneys, radio, and television
antennas. - ANSWER3 Feet (NEC 225.19 B)
The NEC classifies Continuous Load as equipment running at a maximum load of __
____? - ANSWER3 hours
A continuous load is a load where the maximum current is expected to continue for a
certain length of time. This amount of time is? - ANSWER3 hours or more
The minimum head room of working space above service equipment, switchboards,
panel boards, or motor control centers shall be at least: - ANSWER6.5 feet
What is the minimum required separation between communication cables and lighting
conductors? - ANSWER6 feet
, What is the minimum separation required between coaxial cable in a CATV system and
lighting conductors - ANSWER6 feet
On a radio antenna receiving station what is the minimum clearance between lead-in
conductors and conductors forming a part of a lightning protection system? - ANSWER6
feet
What is the minimum length of a grounding rod in an application of less than 50 volts? -
ANSWER8 Feet (NEC 250.5.2.5)
Utility owned low-voltage communication, radio, and television coaxial cables may pass
directly over a pool if at a minimum height of: - ANSWER10 feet
All of the following is acceptable as a ground except? - ANSWER10 foot gas pipe (NEC
250.5.2 A)
An antenna is installed on a building for signal reception, what is the smallest size
copper grounding conductor that would be permitted? - ANSWER10 Gauge (NEC
810.21.8 H)
Electrical conduit buried 18 inches below grade shall have a warning tape at how many
inches above the conduit? - ANSWER12 inches (NEC 300.5 D 3)
What is the smallest ground wire to to communications box - ANSWER14 AWG (NEC
830.100 A 3)
What is the minimum size grounding conductor for communications circuits -
ANSWER14 AWG
What is the maximum interval the fire alarm signal is allowed at the consul? -
ANSWER15 Seconds (NFPA 72 23.8.1.3.1.1)
What is the minimum wire size for connecting bells, sirens, or control circuitry? -
ANSWER18 AWG (NEC 760.49 A)
According to NEC class 3 circuits are allowed a minimum wire size of what gauge? -
ANSWER18 AWG (NEC 725.179 H)
What is the maximum number of supervisory switches permitted to be connected to a
actuate a single transmitter? - ANSWER20
Type PLTC nonmetallic sheathed shall be a minimum size ___ gauge for class 3 circuits
and have an insulation rating of atleast 300 V - ANSWER22 (NEC 725.179 E)
QUESTIONS AND ANSWERS
What is the minimum clearance to the edge of a wood stud for a wire hole? - ANSWER1
1/4 inches(NEC 300.4 A 1)
What is the minimum separation between a class 1 fire alarm circuit conductor and a
class 2 or class 3 circuit? - ANSWER1/4 inch
A basic alarm system will have __ power sources. - ANSWER2
What is the minimum required clearance between a receiving antenna and 250 volt line
not insulated? - ANSWER2 Feet
The minimum clearance for an antenna to other conductors is? - ANSWER2 Feet (NEC
810.13)
How far away must communications cables be from electric, light, or power conductors -
ANSWER2 inches
what is the maximum blink rate on a strobe light per second? - ANSWER2 (NFPA 72
18.5.2.1)
On a voice alarm system what is the minimum number of cycles it has to report an
evacuation procedure? - ANSWER2 (NFPA 72 24.4.1.2.1)
What is the minimum required height for a propriety manual pull fire alarm? - ANSWER3
1/2 feet or 42 inches
An overhead feeder must have a clearance of __ from chimneys, radio, and television
antennas. - ANSWER3 Feet (NEC 225.19 B)
The NEC classifies Continuous Load as equipment running at a maximum load of __
____? - ANSWER3 hours
A continuous load is a load where the maximum current is expected to continue for a
certain length of time. This amount of time is? - ANSWER3 hours or more
The minimum head room of working space above service equipment, switchboards,
panel boards, or motor control centers shall be at least: - ANSWER6.5 feet
What is the minimum required separation between communication cables and lighting
conductors? - ANSWER6 feet
, What is the minimum separation required between coaxial cable in a CATV system and
lighting conductors - ANSWER6 feet
On a radio antenna receiving station what is the minimum clearance between lead-in
conductors and conductors forming a part of a lightning protection system? - ANSWER6
feet
What is the minimum length of a grounding rod in an application of less than 50 volts? -
ANSWER8 Feet (NEC 250.5.2.5)
Utility owned low-voltage communication, radio, and television coaxial cables may pass
directly over a pool if at a minimum height of: - ANSWER10 feet
All of the following is acceptable as a ground except? - ANSWER10 foot gas pipe (NEC
250.5.2 A)
An antenna is installed on a building for signal reception, what is the smallest size
copper grounding conductor that would be permitted? - ANSWER10 Gauge (NEC
810.21.8 H)
Electrical conduit buried 18 inches below grade shall have a warning tape at how many
inches above the conduit? - ANSWER12 inches (NEC 300.5 D 3)
What is the smallest ground wire to to communications box - ANSWER14 AWG (NEC
830.100 A 3)
What is the minimum size grounding conductor for communications circuits -
ANSWER14 AWG
What is the maximum interval the fire alarm signal is allowed at the consul? -
ANSWER15 Seconds (NFPA 72 23.8.1.3.1.1)
What is the minimum wire size for connecting bells, sirens, or control circuitry? -
ANSWER18 AWG (NEC 760.49 A)
According to NEC class 3 circuits are allowed a minimum wire size of what gauge? -
ANSWER18 AWG (NEC 725.179 H)
What is the maximum number of supervisory switches permitted to be connected to a
actuate a single transmitter? - ANSWER20
Type PLTC nonmetallic sheathed shall be a minimum size ___ gauge for class 3 circuits
and have an insulation rating of atleast 300 V - ANSWER22 (NEC 725.179 E)
