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NETA ETT Level 4 study materials
NETA ETT Level 4 study resources

NETA ETT Level 4 practice questions

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Question 1Electrical Safety and Hazard Control

Before any work begins on de-energized electrical equipment, which step must immediately follow the isolation of all energy sources in a lockout/tagout procedure?

  1. Post warning signs at the building entrance
  2. Notify the utility company of the planned outage
  3. Apply locks and tags to each energy-isolating device
  4. Verify the absence of voltage at the point of work Correct answer.

Explanation

After isolating and locking out all energy sources, the qualified person must verify the equipment is de-energized, typically by testing with a meter rated for the voltage present. Verification confirms that the correct source was isolated and that stored or backfed energy is not present before work proceeds.

Question 2Electrical Safety and Hazard Control

A worker must reset a tripped breaker in a panelboard where the cover has been removed. Which personal protective equipment is most appropriate for the task?

  1. Leather work boots and a hard hat only
  2. Non-conductive rubber-soled shoes and a dust mask
  3. Cotton work gloves and safety glasses
  4. Arc-rated face shield, arc-rated clothing, and voltage-rated gloves Correct answer.

Explanation

Working near exposed energized parts exposes the worker to arc flash and shock hazards, so arc-rated protection and voltage-rated gloves are required. Ordinary work gloves and glasses provide no arc or shock protection.

Question 3Electrical Safety and Hazard Control

What is the primary purpose of an arc flash boundary in an electrical safety program?

  1. To mark where qualified workers must wear shock-protective gloves
  2. To separate high-voltage from low-voltage equipment rooms
  3. To define the distance at which incident energy could cause a second-degree burn Correct answer.
  4. To indicate the maximum reach of a portable ladder

Explanation

The arc flash boundary is the approach limit at which a person could receive an incident energy of 1.2 cal/cm2, roughly the onset of a second-degree burn. Inside that boundary, arc-rated protection is required.

Question 4Electrical Safety and Hazard Control

Which condition most clearly indicates that a portable electrical tool must be removed from service?

  1. The tool is stored in a metal cabinet
  2. The equipment grounding conductor is missing from the plug Correct answer.
  3. The tool's cord is longer than three meters
  4. The tool has a slightly scuffed outer housing

Explanation

A missing equipment grounding conductor eliminates the fault-current path that protects the user, so the tool is unsafe and must be tagged out of service. Cosmetic damage or storage location does not by itself create a shock hazard.

Question 5Electrical Safety and Hazard Control

A worker receives a shock but is not injured and shows no symptoms. What should happen next?

  1. The worker returns to the task after a short break
  2. The circuit is reset and work continues without further action
  3. The worker is reassigned to a different crew without documentation
  4. The event is reported and the equipment is inspected before reuse Correct answer.

Explanation

Any electric shock is an incident that must be reported and investigated, because it can indicate an insulation failure or grounding defect. The equipment should be inspected and, if faulty, removed from service before reuse.

Question 6Electrical Safety and Hazard Control

Which factor most strongly increases the severity of injury from electric shock to the human body?

  1. The color of the conductor insulation
  2. The duration of current flow through the body Correct answer.
  3. The length of the extension cord
  4. The ambient noise level in the work area

Explanation

Shock severity depends mainly on current magnitude and the time the current flows through the body. Longer exposure increases the risk of ventricular fibrillation and tissue damage.

Question 7Electrical Safety and Hazard Control

What does an energized electrical work permit authorize?

  1. Any worker to perform energized work without further review
  2. Specifically identified energized work under defined safe conditions Correct answer.
  3. Work on de-energized circuits only
  4. Permanent removal of lockout devices from a panel

Explanation

An energized electrical work permit documents justification, hazard analysis, and required safeguards for a specific task. It authorizes only the identified work under the stated conditions, not open-ended energized work.

Question 8Electrical Safety and Hazard Control

A technician is measuring voltage on a 480 V panel with a multimeter. The meter's category rating is CAT II. What is the correct action?

  1. Proceed because the test leads are insulated
  2. Use a meter rated for the available fault energy and location category Correct answer.
  3. Measure only one phase to reduce exposure
  4. Proceed because the meter is digital

Explanation

Test instruments must be rated for the voltage and fault current available at the measurement point. A CAT II meter is not suitable for a 480 V panelboard, which requires a higher category rating such as CAT III or CAT IV.

Question 9Electrical Safety and Hazard Control

An employer determines that de-energizing equipment would introduce a greater hazard than working energized. What must be documented to justify energized work?

  1. A verbal agreement among the crew
  2. A note in the maintenance log after the work
  3. A purchase order for new test equipment
  4. A written justification and an energized electrical work permit Correct answer.

Explanation

Energized work is permitted only when de-energizing would increase hazard or is infeasible, and that determination must be documented with justification and a permit. The permit records the hazard analysis and required safeguards.

Question 10Electrical Safety and Hazard Control

Two workers are working near a 13.8 kV switchgear lineup. Which approach boundary requires the use of shock-protective equipment and is closest to the exposed live parts?

  1. The arc flash boundary
  2. The restricted approach boundary Correct answer.
  3. The equipment clearance boundary
  4. The limited approach boundary

Explanation

The restricted approach boundary is the closest shock boundary and requires qualified workers to use shock-protective equipment and insulated tools. Only qualified persons may cross it, and inadvertent movement must be controlled.

Question 11Electrical Safety and Hazard Control

What is the purpose of equipotential bonding around a work area near energized high-voltage equipment?

  1. To keep all conductive objects at the same potential and reduce shock risk Correct answer.
  2. To increase the fault current available to trip breakers faster
  3. To provide a low-resistance path to ground for lightning
  4. To measure the insulation resistance of the equipment

Explanation

Equipotential bonding connects conductive objects so they sit at the same electrical potential, preventing dangerous differences from developing across a worker's body. It is a key control for high-voltage work.

Question 12Electrical Safety and Hazard Control

A maintenance crew is replacing a motor. The disconnect is locked out, but a variable-frequency drive remains connected. What additional hazard control is required?

  1. Increase the lockout tag size for visibility
  2. No additional control is needed because the disconnect is locked
  3. Wait for the drive's stored energy to dissipate and verify zero voltage Correct answer.
  4. Ask the operator to watch the drive during the work

Explanation

Variable-frequency drives contain capacitors that store energy after the supply is removed. The worker must allow the drive to discharge for the manufacturer's specified time and then verify the absence of voltage before touching conductors.

Question 13Electrical Safety and Hazard Control

Which practice best reduces the risk of arc flash when racking a circuit breaker into an energized switchgear compartment?

  1. Racking the breaker quickly to minimize exposure time
  2. Using remote racking equipment and standing outside the arc flash boundary Correct answer.
  3. Wearing only safety glasses for eye protection
  4. Standing directly in front of the compartment

Explanation

Remote racking keeps the operator outside the arc flash boundary and away from the compartment door. This is a preferred engineering control for a task with high arc flash risk.

Question 14Electrical Safety and Hazard Control

What is the minimum safe practice when a worker must enter a confined space containing electrical equipment?

  1. Enter alone to reduce the number of people exposed
  2. Prop the entry hatch open and proceed
  3. Test the atmosphere, isolate energy, and use an attendant Correct answer.
  4. Rely on natural ventilation only

Explanation

Confined space entry requires atmospheric testing, energy isolation, and a trained attendant outside the space. These controls address both atmospheric and electrical hazards.

Question 15Electrical Safety and Hazard Control

A grounding conductor for a temporary power distribution system is found to be undersized for the available fault current. What is the consequence?

  1. The system will operate more efficiently
  2. Fault current may not clear quickly, prolonging shock and arc hazards Correct answer.
  3. The circuit breaker will trip more sensitively
  4. The voltage will rise above nominal

Explanation

An undersized grounding conductor has higher impedance, which limits fault current and can delay or prevent protective device operation. The result is prolonged touch voltage and greater arc exposure.

Question 16Electrical Safety and Hazard Control

Which statement correctly describes the relationship between incident energy and working distance from an arc source?

  1. Incident energy decreases as distance increases Correct answer.
  2. Incident energy is independent of distance
  3. Incident energy increases as distance increases
  4. Incident energy depends only on the source voltage

Explanation

Incident energy falls off with distance from the arc source, which is why increasing working distance is a recognized control. Arc-rated protection levels are selected for the energy at the actual working distance.

Question 17Electrical Safety and Hazard Control

A worker is using a non-contact voltage tester on a conductor that is part of a multi-wire branch circuit. The tester indicates no voltage, but the neutral is shared. What should the worker do before touching the conductor?

  1. Verify with a second method and confirm all circuit sources are isolated Correct answer.
  2. Test only the neutral conductor
  3. Assume the circuit is de-energized because the tester is new
  4. Trust the tester and proceed

Explanation

Non-contact testers can give false readings, and shared neutrals can remain energized from another circuit. A second verification method and confirmation that all sources are isolated are required before contact.

Question 18Electrical Safety and Hazard Control

Which of the following is the best example of an engineering control for electrical hazard reduction?

  1. Installing insulated barriers over exposed busbars Correct answer.
  2. Requiring arc-rated clothing
  3. Posting warning signs at the panel
  4. Training workers on arc flash awareness

Explanation

Engineering controls remove or isolate the hazard at its source, such as physical barriers over exposed conductors. Training, PPE, and signage are administrative or PPE controls that depend on human behavior.

Question 19Electrical Safety and Hazard Control

A 480 V motor circuit is locked out at the local disconnect, but the motor starter is fed from a remote MCC bucket. What is the most likely reason the circuit could still be energized?

  1. The lockout tag was the wrong color
  2. The motor is not bonded
  3. Multiple energy sources feed the equipment Correct answer.
  4. The disconnect is rated for a higher voltage

Explanation

Equipment fed from more than one source, such as a remote MCC bucket or control circuit, can remain energized even when the local disconnect is locked. All sources must be identified and isolated.

Question 20Electrical Safety and Hazard Control

A qualified worker calculates an incident energy of 8 cal/cm2 at the working distance. Which arc-rated clothing selection is appropriate?

  1. Arc-rated clothing rated for half the calculated energy
  2. Arc-rated clothing with a rating at least equal to the calculated incident energy Correct answer.
  3. No arc-rated clothing is needed
  4. Ordinary cotton coveralls with a flame-resistant treatment

Explanation

Arc-rated clothing must have an arc rating equal to or greater than the calculated incident energy at the working distance. Selecting a lower rating leaves the worker under-protected.

Question 21Electrical Safety and Hazard Control

During a fault, a grounding electrode conductor is found to be carrying significant current continuously. What does this most likely indicate?

  1. The grounding system is functioning normally
  2. A neutral-to-ground bond exists downstream of the service Correct answer.
  3. The electrode conductor is oversized
  4. The circuit breakers are coordinated correctly

Explanation

Continuous current on a grounding electrode conductor often indicates an unintended neutral-to-ground connection downstream, which creates a parallel return path. This condition is a hazard and must be corrected.

Question 22Electrical Safety and Hazard Control

A worker is troubleshooting a live control circuit at 120 V and plans to use a meter with damaged test lead insulation. What is the correct decision?

  1. Use the meter only on the lowest voltage range
  2. Wrap the damaged lead with electrical tape and proceed
  3. Hold the damaged section with an insulated glove
  4. Replace the damaged leads before performing the measurement Correct answer.

Explanation

Damaged test lead insulation compromises the only barrier between the worker and the live conductor. Leads must be replaced, not repaired with tape, before any measurement.

Question 23Electrical Safety and Hazard Control

What is the primary reason that a lockout device should be individually keyed to the worker applying it?

  1. To allow supervisors to remove any lock quickly
  2. To ensure only the person who applied the lock can remove it Correct answer.
  3. To comply with color-coding requirements
  4. To reduce the number of keys the employer must purchase

Explanation

Individual keying ensures that the worker who applied the lock controls its removal, preventing another person from re-energizing the equipment while work is in progress. Removal by others is allowed only under a documented exception procedure.

Question 24Electrical Safety and Hazard Control

An arc flash study shows that the available incident energy at a switchgear location exceeds the rating of the arc-rated clothing on site. Which control strategy is most effective?

  1. Change the equipment settings or design to reduce incident energy Correct answer.
  2. Add a second worker as a spotter
  3. Shorten the work task to reduce exposure time
  4. Post a sign warning of the high incident energy

Explanation

Reducing incident energy at the source, through protective device settings, equipment design, or maintenance mode switches, is the most effective way to lower the hazard. Administrative measures and signage do not reduce the energy.

Question 25AC and DC Circuit Theory and Analysis

In a purely resistive AC circuit, what is the phase relationship between the applied voltage and the current?

  1. Current lags voltage by 90 degrees
  2. Current and voltage are exactly in phase Correct answer.
  3. Current leads voltage by 90 degrees
  4. Current leads voltage by 45 degrees

Explanation

In a resistance, opposition to current flow does not depend on the rate of change, so the current rises and falls together with the applied voltage. The phase angle between them is zero, giving a power factor of one. Only reactive elements (inductors and capacitors) introduce a 90-degree phase shift.

Question 26AC and DC Circuit Theory and Analysis

A 12 V battery is connected across a 4 ohm resistor. What current flows through the resistor?

  1. 16 A
  2. 3 A Correct answer.
  3. 48 A
  4. 0.33 A

Explanation

Ohm's law states that current equals voltage divided by resistance, so I = 12 V / 4 ohm = 3 A. This is the fundamental relationship used to size conductors and protective devices. Multiplying or dividing the wrong quantities gives the other choices.

Question 27AC and DC Circuit Theory and Analysis

Two resistors of 6 ohm and 3 ohm are connected in parallel. What is the equivalent resistance of the combination?

  1. 9 ohm
  2. 18 ohm
  3. 4.5 ohm
  4. 2 ohm Correct answer.

Explanation

For two resistors in parallel, the reciprocal of the equivalent resistance is the sum of the reciprocals: 1/6 + 1/3 = 1/2, so Req = 2 ohm. The result is always smaller than the smallest branch resistance, which is a useful check. Series addition would give 9 ohm, which is incorrect here.

Question 28AC and DC Circuit Theory and Analysis

Which component stores energy in a magnetic field when current flows through it?

  1. Resistor
  2. Diode
  3. Inductor Correct answer.
  4. Capacitor

Explanation

An inductor stores energy in the magnetic field created by current through its coil, with energy equal to one half L times current squared. A capacitor instead stores energy in an electric field between its plates. This distinction underlies the opposite phase behavior of the two reactive elements.

Question 29AC and DC Circuit Theory and Analysis

What is the RMS value of a sinusoidal voltage whose peak value is 170 V?

  1. 170 V
  2. 120 V Correct answer.
  3. 85 V
  4. 340 V

Explanation

For a sine wave, RMS equals peak divided by the square root of two, so 170 / 1.414 is approximately 120 V. The RMS value is the equivalent DC value that produces the same heating effect. This is why nominal 120 V distribution corresponds to about a 170 V peak.

Question 30AC and DC Circuit Theory and Analysis

In a series DC circuit, how does the current behave at every point in the loop?

  1. It decreases after each resistor
  2. It is the same through every component Correct answer.
  3. It increases after each resistor
  4. It splits in proportion to resistance

Explanation

A series circuit provides only one path, so the same current must pass through every element by conservation of charge. Voltage, not current, divides across the components in proportion to their resistance. Current splitting occurs only at parallel branch points.

Question 31AC and DC Circuit Theory and Analysis

A coil has an inductive reactance of 30 ohm and is in series with a 40 ohm resistor. What is the magnitude of the total impedance?

  1. 50 ohm Correct answer.
  2. 10 ohm
  3. 35 ohm
  4. 70 ohm

Explanation

Impedance magnitude for a series R-L circuit is the square root of R squared plus XL squared, so the square root of 1600 + 900 = 50 ohm. Resistance and reactance add as perpendicular phasors, not arithmetically. This 3-4-5 relationship is a common quick check.

Question 32AC and DC Circuit Theory and Analysis

In a series RLC circuit at resonance, which statement is true?

  1. Capacitive reactance exceeds inductive reactance
  2. The circuit draws minimum current from the source
  3. Resistance equals the total reactance
  4. Inductive reactance equals capacitive reactance and they cancel Correct answer.

Explanation

At resonance XL equals XC, so their phasors cancel and the impedance reduces to resistance alone. The circuit then draws its maximum current for a given source voltage because impedance is at its minimum. The phase angle is zero at this point.

Question 33AC and DC Circuit Theory and Analysis

What is the time constant of a series RC circuit with a 100 kohm resistor and a 10 microfarad capacitor?

  1. 1 second Correct answer.
  2. 0.1 second
  3. 10 seconds
  4. 0.001 second

Explanation

The RC time constant equals R times C, so 100,000 ohm times 0.000010 F = 1 second. After one time constant the capacitor charges to about 63 percent of the supply voltage. The time constant governs how quickly the circuit responds to changes.

Question 34AC and DC Circuit Theory and Analysis

A 60 Hz source is applied to a 0.1 H inductor. What is the inductive reactance?

  1. 377 ohm
  2. 37.7 ohm Correct answer.
  3. 0.6 ohm
  4. 6 ohm

Explanation

Inductive reactance equals 2 pi f L, so 2 times 3.1416 times 60 times 0.1 gives approximately 37.7 ohm. Reactance rises with both frequency and inductance. This value sets how much the coil opposes AC while passing DC freely.

Question 35AC and DC Circuit Theory and Analysis

In a parallel circuit, how does voltage behave across each branch?

  1. It is greatest across the highest resistance branch
  2. It divides in proportion to branch resistance
  3. It equals the source voltage across every branch Correct answer.
  4. It is zero across branches with no current

Explanation

Parallel branches share the same two nodes, so each branch sees the full source voltage regardless of its resistance. Current, not voltage, divides among the branches. This is the basis for household wiring, where every outlet receives the same supply voltage.

Question 36AC and DC Circuit Theory and Analysis

A circuit has a power factor of 0.8 lagging with an apparent power of 500 VA. What is the real power consumed?

  1. 100 W
  2. 500 W
  3. 625 W
  4. 400 W Correct answer.

Explanation

Real power equals apparent power times the power factor, so 500 VA times 0.8 = 400 W. The remaining 300 var is reactive power that oscillates but does no useful work. A lagging factor indicates an inductive load.

Question 37AC and DC Circuit Theory and Analysis

What is the capacitive reactance of a 50 microfarad capacitor at 60 Hz?

  1. 18.8 ohm
  2. 188 ohm
  3. 53.1 ohm Correct answer.
  4. 0.019 ohm

Explanation

Capacitive reactance equals 1 divided by 2 pi f C, so 1 / (2 times 3.1416 times 60 times 0.000050) is approximately 53.1 ohm. Unlike inductive reactance, it decreases as frequency rises. This inverse relationship makes capacitors pass high frequencies more readily.

Question 38AC and DC Circuit Theory and Analysis

Kirchhoff's voltage law applied to a closed DC loop states that the algebraic sum of all voltages is zero. What physical principle does this express?

  1. Conservation of momentum
  2. Conservation of charge
  3. Conservation of energy Correct answer.
  4. Conservation of flux linkage

Explanation

Kirchhoff's voltage law follows from energy conservation: moving a charge around a closed loop and returning to the start must involve zero net work. The sum of source EMFs equals the sum of voltage drops. By contrast, the current law expresses conservation of charge at a node.

Question 39AC and DC Circuit Theory and Analysis

A coil with 200 turns carries a current that changes at 5 A per second, inducing 4 V. What is the inductance?

  1. 0.8 H Correct answer.
  2. 20 H
  3. 1.25 H
  4. 0.2 H

Explanation

The induced voltage equals inductance times the rate of change of current, so L = V / (di/dt) = 4 / 5 = 0.8 H. Self-induced EMF opposes the change that produced it, per Lenz's law. The number of turns affects inductance but is not needed once the voltage and current rate are known.

Question 40AC and DC Circuit Theory and Analysis

A 10 ohm resistor carries a current of 3 A. What power is dissipated?

  1. 90 W Correct answer.
  2. 30 W
  3. 9 W
  4. 300 W

Explanation

Power dissipated by a resistor equals current squared times resistance, so 3 squared times 10 = 90 W. This is the I-squared-R heating that determines component ratings. Using voltage times current would require first finding the 30 V drop, which gives the same result.

Question 41AC and DC Circuit Theory and Analysis

In an AC circuit, a capacitor's current waveform leads its voltage waveform by 90 degrees. What is the practical consequence for reactive power?

  1. The capacitor behaves as a short circuit at all frequencies
  2. The capacitor dissipates real power equal to V times I
  3. The capacitor alternately absorbs and returns energy, drawing no net real power Correct answer.
  4. The capacitor increases the total real power of the circuit

Explanation

Because current and voltage are 90 degrees out of phase, the instantaneous power alternates in sign, so energy flows into the capacitor and back to the source each half cycle. Averaged over a full cycle, the net real power is zero; only reactive power is exchanged. This phase relationship is what makes capacitors useful for power-factor correction.

Question 42AC and DC Circuit Theory and Analysis

A series circuit contains a 6 ohm resistor, an inductive reactance of 10 ohm, and a capacitive reactance of 2 ohm. What is the phase angle of the impedance?

  1. 37 degrees, current leading
  2. 30 degrees, current leading
  3. 45 degrees, current lagging
  4. 53 degrees, current lagging Correct answer.

Explanation

The net reactance is XL minus XC = 10 - 2 = 8 ohm inductive, so the angle is the arctangent of 8/6, about 53 degrees, with current lagging voltage because the net reactance is inductive. Resistance and net reactance form the legs of the impedance triangle. The inductive reactance dominates, so the circuit behaves inductively.

Question 43AC and DC Circuit Theory and Analysis

A coil with inductance L and resistance R is connected to a DC source and reaches steady state. How does the inductor then behave?

  1. It acts as an open circuit and blocks all current
  2. It continues to oppose current with reactance XL
  3. It acts as a short to DC, with current limited only by R Correct answer.
  4. It reverses the polarity of the supply

Explanation

At steady state the current is constant, so the rate of change of current is zero and the induced voltage L di/dt vanishes. The ideal inductor then presents no opposition, and the steady current is set by the series resistance as V/R. Reactance applies only to time-varying currents.

Question 44AC and DC Circuit Theory and Analysis

A sinusoidal source drives a series RLC circuit below its resonant frequency. How does the circuit behave overall?

  1. Capacitive, with current leading voltage Correct answer.
  2. Purely resistive, with current in phase with voltage
  3. Inductive, with current lagging voltage
  4. Oscillatory with zero impedance

Explanation

Below resonance, capacitive reactance exceeds inductive reactance because XC rises as frequency falls while XL falls. The net reactance is therefore capacitive, making the current lead the source voltage. Above resonance the opposite occurs and the circuit becomes net inductive.

Question 45Power System Fundamentals and Equipment

In a balanced three-phase system, what is the relationship between line voltage and phase voltage for a wye-connected source?

  1. Line voltage equals phase voltage exactly
  2. Line voltage equals phase voltage multiplied by the square root of three Correct answer.
  3. Line voltage equals phase voltage divided by the square root of three
  4. Line voltage equals phase voltage multiplied by three

Explanation

In a wye connection each line-to-line voltage spans two phase windings displaced by 120 degrees, so the phasor sum gives a factor of the square root of three. The line current, by contrast, equals the phase current.

Question 46Power System Fundamentals and Equipment

A transformer is rated 500 kVA at 13.8 kV to 480 V. Which statement correctly describes the primary and secondary current relationship in normal operation?

  1. Current is independent of voltage on both sides
  2. Primary current is larger than secondary current by roughly the turns ratio
  3. Secondary current is larger than primary current by roughly the turns ratio Correct answer.
  4. Primary and secondary currents are equal because power is conserved

Explanation

Apparent power equals voltage times current on each side, so the lower-voltage winding carries the higher current. The ratio of currents is the inverse of the voltage ratio, roughly 28.75 for this unit.

Question 47Power System Fundamentals and Equipment

Which device is designed to interrupt fault current and can also be reclosed automatically to restore service after a transient fault?

  1. Recloser Correct answer.
  2. Surge arrester
  3. Current transformer
  4. Disconnect switch

Explanation

A recloser is a self-controlled interrupting device that trips on overcurrent and recloses after a set time to clear temporary faults. Disconnect switches cannot interrupt fault current, arresters limit overvoltage, and current transformers only measure.

Question 48Power System Fundamentals and Equipment

A conductor carries 200 A through a resistance of 0.05 ohm. What is the approximate real power loss in the conductor?

  1. 1000 W
  2. 100 W
  3. 10 W
  4. 2000 W Correct answer.

Explanation

Conductor loss follows I squared R, so 200 squared times 0.05 ohm gives 2000 W. This quadratic relationship is why losses rise steeply with loading and why higher voltage reduces current for the same power.

Question 49Power System Fundamentals and Equipment

What is the primary purpose of a power transformer's conservator tank?

  1. To cool the core by forced air circulation
  2. To accommodate oil expansion and contraction while keeping the main tank full Correct answer.
  3. To increase the transformer's voltage ratio during peak load
  4. To provide a path for fault current to ground

Explanation

The conservator is an oil reservoir mounted above the main tank that absorbs volume changes as oil heats and cools, keeping the main tank full and limiting contact between oil and air. It does not affect ratio, grounding, or forced cooling.

Question 50Power System Fundamentals and Equipment

Which quantity remains essentially constant along a radial distribution feeder when only voltage drop is considered and load power is fixed?

  1. Voltage
  2. Current
  3. Apparent power delivered to the load Correct answer.
  4. Power factor

Explanation

For a fixed load, the apparent power demanded stays the same while voltage falls and current rises slightly along the feeder. Voltage drop is caused by impedance, but the load's power requirement is unchanged.