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Georgia Low Voltage Practice study materials
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Georgia Low Voltage Practice practice questions

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Question 1General Electrical Theory and Fundamentals

In a low voltage circuit, what does the term 'voltage' describe?

  1. The electrical potential difference that drives current between two points Correct answer.
  2. The total resistance offered by the conductors
  3. The thermal energy dissipated by a load over time
  4. The rate at which charge flows past a point in the circuit

Explanation

Voltage is the difference in electric potential between two points, and that potential difference is what pushes charge through a circuit. It is measured in volts and exists even when no current flows, unlike current or power.

Question 2General Electrical Theory and Fundamentals

A low voltage installer needs to express a load of 1,500 milliamperes in amperes. Which value is correct?

  1. 0.15 A
  2. 0.015 A
  3. 1.5 A Correct answer.
  4. 15 A

Explanation

One ampere equals 1,000 milliamperes, so dividing 1,500 mA by 1,000 gives 1.5 A. Metric prefixes in electrical work shift the decimal by powers of ten, and milli means one-thousandth.

Question 3General Electrical Theory and Fundamentals

A 12-volt DC circuit draws 2 amperes. Using Ohm's law relationships, what is the resistance of the load?

  1. 24 ohms
  2. 10 ohms
  3. 6 ohms Correct answer.
  4. 0.167 ohms

Explanation

Ohm's law states that resistance equals voltage divided by current (R = V / I). Substituting 12 V and 2 A gives 6 ohms.

Question 4General Electrical Theory and Fundamentals

Which unit is used to express electrical power in a low voltage system?

  1. Coulomb
  2. Watt Correct answer.
  3. Farad
  4. Ohm

Explanation

Power is the rate of energy transfer and is measured in watts, equal to one joule per second. In electrical terms it equals voltage multiplied by current.

Question 5General Electrical Theory and Fundamentals

A 24-volt power supply feeds a device drawing 0.5 amperes. How much power does the device consume?

  1. 12 W Correct answer.
  2. 0.02 W
  3. 24 W
  4. 48 W

Explanation

Electrical power equals voltage multiplied by current (P = V x I). Multiplying 24 V by 0.5 A yields 12 W.

Question 6General Electrical Theory and Fundamentals

Which material is classified as a conductor in low voltage wiring practice?

  1. Hard-drawn copper Correct answer.
  2. Borosilicate glass
  3. Vulcanized rubber
  4. Dry oak

Explanation

Copper has loosely bound outer electrons that move freely, making it an excellent conductor and the standard material for low voltage conductors. The other listed materials are insulators that impede charge movement.

Question 7General Electrical Theory and Fundamentals

In a series circuit containing three resistors, which statement about current is true?

  1. The same current flows through every resistor Correct answer.
  2. Current is highest through the largest resistor
  3. Current splits proportionally to resistance at each resistor
  4. Current is zero in the segment after the last resistor

Explanation

A series circuit provides only one path for charge, so the same current passes through every element in that path. Voltage divides across the resistors, but current does not.

Question 8General Electrical Theory and Fundamentals

A low voltage circuit has two 8-ohm resistors connected in parallel. What is the equivalent resistance?

  1. 4 ohms Correct answer.
  2. 2 ohms
  3. 16 ohms
  4. 8 ohms

Explanation

For two equal resistors in parallel, the equivalent resistance is half the value of one resistor. Two 8-ohm resistors therefore combine to 4 ohms, matching the product-over-sum formula (64/16).

Question 9General Electrical Theory and Fundamentals

Kirchhoff's current law, applied at a junction in a low voltage circuit, states that:

  1. The total current entering a junction equals the total current leaving it Correct answer.
  2. The current through a branch is proportional to its resistance
  3. The total resistance equals the sum of branch resistances
  4. The sum of voltage drops around any closed loop equals zero

Explanation

Kirchhoff's current law is a statement of charge conservation: charge cannot accumulate at a node, so current in equals current out. It is the basis for analyzing parallel branches and node voltages.

Question 10General Electrical Theory and Fundamentals

A 120-volt source is connected across a 40-ohm load. What current flows?

  1. 4,800 A
  2. 160 A
  3. 3 A Correct answer.
  4. 0.33 A

Explanation

Ohm's law gives current as voltage divided by resistance (I = V / R). Dividing 120 V by 40 ohms yields 3 A.

Question 11General Electrical Theory and Fundamentals

Why is alternating current rather than direct current used for utility power distribution to low voltage transformers?

  1. AC produces no magnetic fields
  2. AC travels only through insulators
  3. AC eliminates the need for grounding
  4. AC can be stepped up or down efficiently with transformers Correct answer.

Explanation

Transformers only change voltage levels with a changing magnetic flux, which requires alternating current. Stepping voltage up for transmission reduces line losses, which is why distribution systems use AC.

Question 12General Electrical Theory and Fundamentals

What is the effective value (RMS) relationship for a sinusoidal voltage in low voltage AC work?

  1. RMS equals the peak-to-peak value
  2. RMS equals half the peak value
  3. RMS equals the peak value multiplied by the square root of two
  4. RMS equals the peak value divided by the square root of two Correct answer.

Explanation

For a sine wave, the RMS value is the peak value divided by approximately 1.414, or about 0.707 times the peak. RMS is used because it represents the equivalent heating effect of the waveform.

Question 13General Electrical Theory and Fundamentals

A resistor with color bands brown, black, red, and gold is read in that order. What is its nominal value?

  1. 1,000 ohms with 5 percent tolerance Correct answer.
  2. 100 ohms with 5 percent tolerance
  3. 1,000 ohms with 10 percent tolerance
  4. 10 ohms with 5 percent tolerance

Explanation

Brown is 1, black is 0, and red as a multiplier means two additional zeros, giving 1,000 ohms. A gold fourth band indicates plus or minus 5 percent tolerance.

Question 14General Electrical Theory and Fundamentals

Which statement correctly distinguishes a short circuit from an open circuit?

  1. A short has near-infinite resistance, while an open has near-zero resistance
  2. Both conditions result in normal current flow
  3. A short occurs only in AC circuits and an open only in DC circuits
  4. A short has near-zero resistance across the source, while an open has near-infinite resistance Correct answer.

Explanation

A short circuit provides an unintended low-resistance path, allowing excessive current that can damage equipment or start a fire. An open circuit breaks the path entirely, so resistance is effectively infinite and no current flows.

Question 15General Electrical Theory and Fundamentals

In a 12-volt DC circuit, three 4-ohm resistors are connected in series. What is the total current?

  1. 36 A
  2. 3 A
  3. 0.33 A
  4. 1 A Correct answer.

Explanation

Series resistances add, giving 12 ohms total. Dividing the 12 V source by 12 ohms yields 1 A, which flows through every resistor.

Question 16General Electrical Theory and Fundamentals

What is the primary purpose of grounding in a low voltage installation?

  1. To convert alternating current into direct current
  2. To increase the current-carrying capacity of conductors
  3. To reduce the resistance of the load
  4. To provide a low-impedance path to earth that limits voltage and clears faults Correct answer.

Explanation

Grounding establishes a reference potential and creates a low-impedance return path so fault current can trip protective devices and limit hazardous voltage on metal parts. It is a safety function, not a performance enhancement.

Question 17General Electrical Theory and Fundamentals

A 60-watt low voltage load operates at 12 volts. What current does it draw?

  1. 72 A
  2. 5 A Correct answer.
  3. 720 A
  4. 0.2 A

Explanation

Rearranging P = V x I gives I = P / V. Dividing 60 W by 12 V yields 5 A, which is the current the supply must deliver.

Question 18General Electrical Theory and Fundamentals

Two resistors of 6 ohms and 3 ohms are connected in parallel across a 12-volt source. What is the total current drawn from the source?

  1. 1.33 A
  2. 6 A Correct answer.
  3. 9 A
  4. 4 A

Explanation

The equivalent resistance of 6 and 3 ohms in parallel is (6 x 3)/(6 + 3) = 2 ohms. Dividing 12 V by 2 ohms gives 6 A total, which also equals the sum of branch currents (2 A plus 4 A).

Question 19General Electrical Theory and Fundamentals

A conductor carrying 10 amperes experiences a voltage drop of 0.5 volts over its length. What is the resistance of that conductor section?

  1. 5 ohms
  2. 20 ohms
  3. 0.05 ohms Correct answer.
  4. 0.5 ohms

Explanation

Resistance equals voltage drop divided by current, so 0.5 V divided by 10 A equals 0.05 ohms. This small value illustrates why long low voltage runs still produce noticeable voltage drop at higher currents.

Question 20General Electrical Theory and Fundamentals

A low voltage lamp rated 24 volts and 12 watts is connected to a 24-volt supply. What is its resistance at rated operation?

  1. 288 ohms
  2. 48 ohms Correct answer.
  3. 2 ohms
  4. 24 ohms

Explanation

First find current: I = P / V = 12 W / 24 V = 0.5 A. Then R = V / I = 24 V / 0.5 A = 48 ohms, or equivalently R = V squared / P.

Question 21General Electrical Theory and Fundamentals

In a circuit with a 24-volt source, a 4-ohm resistor, and a 12-ohm resistor in series, what is the voltage across the 12-ohm resistor?

  1. 24 V
  2. 6 V
  3. 18 V Correct answer.
  4. 12 V

Explanation

Total resistance is 16 ohms, so current is 24 V / 16 ohms = 1.5 A. The voltage across the 12-ohm resistor is 1.5 A x 12 ohms = 18 V, showing that the larger resistance drops more voltage in series.

Question 22General Electrical Theory and Fundamentals

A 12-volt battery delivers 3 amperes for 4 hours. How much energy is delivered?

  1. 12 watt-hours
  2. 576 watt-hours
  3. 36 watt-hours
  4. 144 watt-hours Correct answer.

Explanation

Power is 12 V x 3 A = 36 W, and energy is power multiplied by time: 36 W x 4 h = 144 watt-hours. Energy accounting matters for battery-backed low voltage systems.

Question 23General Electrical Theory and Fundamentals

A technician measures 0 volts across an energized 24-volt DC load while the supply reads 24 volts. Which condition best explains this?

  1. The load resistance is too high
  2. The load is drawing excessive current
  3. The circuit is open between the supply and the load Correct answer.
  4. The supply voltage is too low

Explanation

If the supply is at 24 V but no voltage appears across the load, the conductive path is broken and no current flows, so there is no drop across the load. Voltage appears across an open, not across the intended load.

Question 24General Electrical Theory and Fundamentals

Which statement correctly describes the relationship between resistance and conductor cross-sectional area?

  1. Resistance decreases as conductor length increases
  2. Resistance increases as cross-sectional area increases
  3. Resistance is independent of cross-sectional area
  4. Resistance decreases as cross-sectional area increases Correct answer.

Explanation

Resistance is inversely proportional to cross-sectional area, so a larger conductor offers more paths for charge and lower resistance. It is directly proportional to length and to the material's resistivity.

Question 25Low Voltage Cabling and Wiring Methods

When installing Cat 6 horizontal cable through a metal stud bay in a commercial building, which practice keeps the cable within its listed bend radius and protects it from abrasion?

  1. Bundle the cable tightly with zip ties cinched to the stud
  2. Run the cable diagonally across the stud opening under tension
  3. Route the cable through a listed metal grommet or protective sleeve Correct answer.
  4. Secure the cable with a staple driven snug against the jacket

Explanation

Metallic framing openings can abrade the jacket and violate the manufacturer's minimum bend radius. A listed grommet or protective sleeve shields the cable and preserves the bend radius. Tension and tight bundling also risk deformation of the cable geometry.

Question 26Low Voltage Cabling and Wiring Methods

Which cable jacket rating is required for a cable installed in a plenum air-handling space?

  1. CMX
  2. CMR
  3. CMP Correct answer.
  4. CMG

Explanation

Plenum spaces require cables listed for plenum use, identified by the CMP marking. CMP jackets have limited smoke and flame spread characteristics suitable for air-handling spaces. Other ratings are intended for riser, general, or outdoor use.

Question 27Low Voltage Cabling and Wiring Methods

A technician is terminating Cat 6A cable on a patch panel and must limit untwisting of the pairs at the termination point. Which practice best supports this?

  1. Maintain pair twists as close to the termination as the connector allows Correct answer.
  2. Separate all four pairs and fan them out before punching down
  3. Strip the jacket back several inches to expose more conductor length
  4. Untwist each pair back to the jacket to make conductor placement easier

Explanation

Untwisting pairs introduces crosstalk and impedance changes near the termination. Keeping the twists intact up to the connector limits near-end crosstalk and preserves the cable's performance margin. Excess jacket removal and fanning the pairs increase the exposed parallel conductor length.

Question 28Low Voltage Cabling and Wiring Methods

Which conductor size is commonly specified for horizontal twisted-pair cabling in a commercial low-voltage installation?

  1. 12 AWG
  2. 18 AWG
  3. 8 AWG
  4. 24 AWG Correct answer.

Explanation

Horizontal twisted-pair cable typically uses 24 AWG conductors, with some products using 23 AWG. Larger sizes such as 18 or 12 AWG are used for power and low-voltage control circuits, not data horizontal runs. The smaller 24 AWG size balances flexibility and electrical performance.

Question 29Low Voltage Cabling and Wiring Methods

A low-voltage installer is routing cable above a suspended ceiling that is used as an air return. Which rating should the installer select?

  1. Cable listed only for riser use
  2. Cable listed for plenum spaces Correct answer.
  3. Cable with no jacket marking
  4. Any cable with a CMG marking

Explanation

A ceiling used as an air return creates a plenum air-handling space, so plenum-listed cable is required. The CMP marking identifies cable with suitable smoke and flame spread characteristics. Riser and general-purpose ratings do not satisfy plenum requirements.

Question 30Low Voltage Cabling and Wiring Methods

Which wiring method is acceptable for protecting exposed low-voltage cable in a finished office area where the cable runs along the wall to a workstation?

  1. Cable laid loosely across the floor
  2. Cable suspended from the ceiling grid
  3. Cable stapled directly to the drywall
  4. Surface-mounted raceway or molding Correct answer.

Explanation

Surface raceway or molding provides physical protection and a finished appearance for exposed cable runs. Loose floor cable and cables suspended from the ceiling grid create trip and strain hazards and are not proper support methods. Direct stapling can damage the jacket.

Question 31Low Voltage Cabling and Wiring Methods

What is the primary purpose of a cable support such as J-hooks in a low-voltage installation?

  1. To serve as a substitute for a grounding conductor
  2. To provide a return path for signal current
  3. To electrically bond the cable to the building structure
  4. To carry the cable weight and control bend radius without crushing it Correct answer.

Explanation

J-hooks support cable weight and maintain a controlled bend radius while avoiding the crushing that tight fasteners cause. They are not electrical bonding components. Support spacing and load limits are governed by the manufacturer and applicable codes.

Question 32Low Voltage Cabling and Wiring Methods

Which practice is correct when pulling cable through a conduit run that contains multiple bends?

  1. Tie the pull rope directly to the conductors
  2. Exceed the bend radius to shorten the pull path
  3. Use pulling lubricant and avoid exceeding the cable's tension limit Correct answer.
  4. Pull as fast as possible to reduce friction time

Explanation

Lubricant reduces friction and helps keep pulling tension within the cable manufacturer's limit. Exceeding tension or bend radius can stretch conductors and permanently degrade performance. The pull rope should be attached to the jacket or a pulling grip, not directly to conductors.

Question 33Low Voltage Cabling and Wiring Methods

A pathway crosses a corridor above a removable ceiling and must support several bundled Cat 6 cables over a long span. Which method best maintains support and separation?

  1. Suspend the bundle from independent supports at intervals set by the manufacturer Correct answer.
  2. Rest the bundle on ductwork
  3. Lay the bundle on the ceiling tile grid
  4. Tie the bundle to a sprinkler pipe

Explanation

Independent supports spaced per the manufacturer carry the load and maintain cable geometry. Ceiling grid, sprinkler pipe, and ductwork are not intended to carry cable loads and may violate code or damage those systems. Separation from other trades also eases future maintenance.

Question 34Low Voltage Cabling and Wiring Methods

When is it acceptable to use an abandoned cable pathway in a commercial building for new low-voltage cabling?

  1. Whenever the pathway appears physically intact
  2. Only when the pathway is concealed in a wall
  3. Only if the original cable is left in place
  4. After confirming the pathway is suitable, accessible, and code-compliant for the new cable Correct answer.

Explanation

Reusing a pathway requires verifying that it is suitable for the new cable type, remains accessible where required, and complies with applicable codes. Visual appearance alone does not establish suitability. Abandoned cable may also need removal per local rules.

Question 35Low Voltage Cabling and Wiring Methods

Which condition requires firestopping of a low-voltage cable penetration?

  1. A cable passing through a rated fire-resistive wall assembly Correct answer.
  2. A cable entering a surface raceway on a drywall partition
  3. A cable terminated on a patch panel in a rack
  4. A cable supported by a J-hook in an open ceiling

Explanation

Penetrations of rated fire-resistive assemblies must be sealed with a listed firestop system to maintain the assembly's rating. Surface raceway entry, J-hook support, and rack termination do not breach a rated assembly. Firestop systems must match the assembly and penetration type.

Question 36Low Voltage Cabling and Wiring Methods

A technician must route a cable through a rated wall and finds no listed firestop system for the specific cable and wall combination on hand. What is the appropriate action?

  1. Enlarge the opening so the cable fits loosely
  2. Leave the penetration open until a later maintenance visit
  3. Select a listed firestop system evaluated for that assembly and cable type Correct answer.
  4. Seal the opening with general-purpose caulk and proceed

Explanation

Firestop systems are tested as assemblies and must be listed for the specific wall type, penetration, and cable. General caulk is not a substitute for a listed system. Leaving a rated penetration open compromises the fire-resistive assembly.

Question 37Low Voltage Cabling and Wiring Methods

Which separation practice is recommended when routing low-voltage communications cable parallel to branch-circuit power conductors in a ceiling space?

  1. Wrap the communications cable around the power conduit
  2. Maintain the manufacturer's or applicable separation distance to limit interference Correct answer.
  3. Cross the power conductors at many points along the run
  4. Bundle the cables together to save space

Explanation

Maintaining separation between communications and power conductors limits electromagnetic interference and is often required by code or manufacturer guidance. Bundling together and repeated crossing increase coupling. Wrapping around conduit maximizes interference.

Question 38Low Voltage Cabling and Wiring Methods

Which marking on a cable jacket indicates it is suitable for use in a riser shaft?

  1. CL3P
  2. CMX
  3. CMP
  4. CMR Correct answer.

Explanation

The CMR marking identifies communications riser cable intended for vertical shafts between floors. CMP is a plenum rating and CMX is a limited-use rating. CL3P is a Class 3 plenum-rated cable marking, not a communications riser marking.

Question 39Low Voltage Cabling and Wiring Methods

A low-voltage installer is asked to install cable in a wet location outdoors. Which cable characteristic is most important?

  1. A jacket listed and marked for wet or outdoor use Correct answer.
  2. A plenum-rated jacket only
  3. A jacket with no UV resistance
  4. A conductor size of 24 AWG only

Explanation

Wet and outdoor locations require cable listed and marked for that environment, including moisture and sunlight resistance. Plenum ratings address smoke and flame spread, not water exposure. Conductor size alone does not establish suitability for wet locations.

Question 40Low Voltage Cabling and Wiring Methods

Which practice is correct when installing cable in a cable tray that also carries power conductors?

  1. Use a barrier or maintain the required separation within the tray Correct answer.
  2. Remove tray covers to improve airflow
  3. Lay communications cable loosely across the power conductors
  4. Tie communications cable to the power conductors

Explanation

Where communications and power cables share a tray, a listed barrier or required separation must be maintained to limit interference and meet code. Laying cable across power conductors and tying them together create coupling and safety hazards. Tray covers serve physical protection and are not removed for airflow.

Question 41Low Voltage Cabling and Wiring Methods

A technician is installing cable in a metal raceway and must calculate fill. Which consideration applies to low-voltage communications cable?

  1. Only the largest cable in the bundle counts toward fill
  2. Fill is unlimited because communications cable carries no power
  3. The number of cables must not exceed the raceway's permitted fill for the cable type Correct answer.
  4. Fill is determined solely by the raceway color

Explanation

Raceway fill limits apply to communications cable to prevent jacket damage during pulls and to preserve performance. Fill is based on cable cross-sectional area and the applicable code or manufacturer allowance. Raceway color and cable count alone do not determine fill.

Question 42Low Voltage Cabling and Wiring Methods

What is the main reason to avoid sharp bends at the point where cable exits a conduit into a junction box?

  1. To increase signal attenuation intentionally
  2. To allow the cable to be stapled more easily
  3. To prevent exceeding the bend radius and damaging conductors or jacket Correct answer.
  4. To reduce the cable's electrical resistance

Explanation

Sharp bends at conduit exits can exceed the minimum bend radius, kinking the cable and damaging conductors or the jacket. Resistance and attenuation are not intentionally altered by bend geometry. Proper bend control preserves the cable's electrical performance.

Question 43Low Voltage Cabling and Wiring Methods

Which item is required to bond metallic communications raceway and cable sheath to the building grounding system?

  1. A cable label
  2. A patch cord
  3. A plastic tie wrap
  4. A listed bonding conductor sized per code Correct answer.

Explanation

Metallic raceway and cable sheath must be bonded to the building grounding system using a listed bonding conductor sized per code. Plastic ties, labels, and patch cords do not provide electrical bonding. Proper bonding limits potential differences and protects equipment.

Question 44Low Voltage Cabling and Wiring Methods

A customer wants cable concealed in a wall with no accessible pathway. Which method is appropriate for future serviceability and code compliance?

  1. Install a listed raceway or conduit within the wall Correct answer.
  2. Bury the cable loosely in the wall cavity with no support
  3. Staple the cable to the exterior siding
  4. Run the cable through the attic and drop it outside the wall

Explanation

A listed raceway or conduit within the wall provides physical protection and a pathway for future cable replacement. Loose unsupported cable in a cavity is not a proper wiring method. Routing outside the wall does not meet the customer's concealment request.

Question 45Low Voltage Cabling and Wiring Methods

Which statement about the minimum bend radius of a twisted-pair cable is accurate?

  1. It is typically expressed as a multiple of the cable's outside diameter Correct answer.
  2. It can be ignored if the cable is supported by J-hooks
  3. It is the same for all cable types regardless of diameter
  4. It applies only during termination, not during pulling

Explanation

Minimum bend radius is generally specified as a multiple of the cable's outside diameter and applies during pulling, routing, and termination. Larger-diameter cables therefore have larger absolute bend radii. Support by J-hooks does not exempt the installer from bend radius limits.

Question 46Low Voltage Cabling and Wiring Methods

During a site survey, an installer finds existing Cat 5e cable stapled tightly to wood studs. Which concern is most relevant to the new cabling plan?

  1. Staples improve crosstalk performance
  2. Compression from staples may have degraded the existing cable, so replacement should be considered Correct answer.
  3. The cable is automatically plenum-rated
  4. The staples guarantee proper support and can be reused

Explanation

Tight staples compress the cable and can deform the pair geometry, degrading performance over time. Existing cable that has been compressed should be evaluated and often replaced. Staples do not improve performance or establish a plenum rating.

Question 47Low Voltage Cabling and Wiring Methods

Which practice best protects a cable during a long horizontal pull through multiple J-hooks?

  1. Allow the cable to drag over the hooks without a pulling lubricant
  2. Use a cable pulling lubricant and support the cable to avoid abrasion Correct answer.
  3. Pull the cable with a vehicle to increase speed
  4. Pull the cable at an angle across the hook openings

Explanation

Lubricant and proper support reduce friction and abrasion during long pulls. Dragging over hooks and pulling at an angle abrade the jacket and stress the conductors. Vehicle-assisted pulling can easily exceed the cable's tension limit.

Question 48Low Voltage Cabling and Wiring Methods

Which condition indicates that a low-voltage cable pathway must be re-evaluated before installation?

  1. The pathway is shared with high-temperature steam piping without separation Correct answer.
  2. The pathway is supported at manufacturer intervals
  3. The pathway is listed for the cable type
  4. The pathway is a dedicated communications raceway

Explanation

Proximity to high-temperature piping can exceed the cable's temperature rating and degrade the jacket, so separation or rerouting is needed. Dedicated raceway, proper support, and correct listing are desirable conditions. Temperature and separation must be verified during design.

Question 49Low Voltage Cabling and Wiring Methods

Which marking indicates a communications cable suitable for general-purpose commercial use in non-plenum, non-riser spaces?

  1. CM Correct answer.
  2. CMX
  3. CMP
  4. CMR

Explanation

The CM marking identifies general-purpose communications cable for use in non-plenum, non-riser locations. CMP and CMR indicate plenum and riser suitability, respectively. CMX is a limited-use rating and is not the general commercial marking.

Question 50Low Voltage Cabling and Wiring Methods

A low-voltage installer is choosing a cable for a return-air plenum ceiling in a commercial building. Which cable rating is specifically listed for use in that air-handling space?

  1. CMG
  2. CMP Correct answer.
  3. CMX
  4. CMR

Explanation

CMP is the plenum-rated communications cable designation, meaning it has passed the appropriate flame and smoke test for installation in air-handling spaces such as return-air plenums. CMR, CMG, and CMX are rated for other locations and do not carry the plenum listing required in that environment.