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HSC Electrotechnology (VET) study materials
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HSC Electrotechnology (VET) practice questions

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Question 1Electrotechnology (Stage 6 VET Board Endorsed Course)

Which document must be consulted before starting work on an electrical installation to identify the required cable size and protective device rating?

  1. The site safety induction record
  2. The toolbox talk sign-off sheet
  3. The electrical installation design documentation Correct answer.
  4. The manufacturer's warranty card

Explanation

Electrical work must follow the design documentation for the installation, which specifies cable sizes, protective devices, and circuit arrangements so the work complies with the wiring rules. Other site paperwork records safety compliance but does not define the technical design.

Question 2Electrotechnology (Stage 6 VET Board Endorsed Course)

Before using a portable electric drill on a construction site, a worker inspects the lead and finds the outer sheath cut through to the conductors. What is the correct action?

  1. Tag the tool out of service and report the damage Correct answer.
  2. Wrap the damaged section with insulation tape and continue
  3. Continue using the drill but keep the lead off the ground
  4. Use the drill only for short periods of low load

Explanation

Damaged supply leads expose live conductors and defeat the protection relied on for safety, so the equipment must be withdrawn from service, tagged, and reported for repair or replacement. Taping or restricting use does not restore the integrity of the insulation.

Question 3Electrotechnology (Stage 6 VET Board Endorsed Course)

In a three-pin plug, what is the function of the earth pin on a Class I appliance?

  1. It reduces the current drawn by the appliance
  2. It carries the operating current back to the supply
  3. It provides a low-resistance path for fault current to operate the protective device Correct answer.
  4. It balances the voltage between active and neutral

Explanation

The protective earth connects exposed conductive parts to the installation earthing system so that a fault creates a low-impedance path that quickly operates the circuit protection. It does not normally carry operating current.

Question 4Electrotechnology (Stage 6 VET Board Endorsed Course)

Which instrument is used to verify that a circuit is de-energised before work begins?

  1. Continuity buzzer
  2. Voltage tester or proving unit combination Correct answer.
  3. Insulation resistance tester
  4. Clamp meter on the highest range

Explanation

A voltage tester, proven on a known live source or proving unit before and after the test, confirms the absence of voltage at the point of work. Insulation and continuity tests do not prove a circuit is isolated from supply.

Question 5Electrotechnology (Stage 6 VET Board Endorsed Course)

A 240 V single-phase circuit draws 10 A. What is the apparent power consumed by the load?

  1. 24 W
  2. 240 W
  3. 24000 W
  4. 2400 W Correct answer.

Explanation

Apparent power for a single-phase circuit equals voltage multiplied by current, so 240 V times 10 A gives 2400 VA, which equals 2400 W for a unity power factor resistive load. The other values result from misplacing the decimal point or using the wrong formula.

Question 6Electrotechnology (Stage 6 VET Board Endorsed Course)

Which of the following is a recognised electrical hazard control measure at the highest level of the hierarchy of control?

  1. Providing rubber gloves to workers
  2. Conducting regular toolbox talks
  3. Eliminating the hazard by de-energising and isolating the circuit Correct answer.
  4. Placing warning signs near the switchboard

Explanation

The hierarchy of control ranks elimination of the hazard highest, and for electrical work that means removing the supply through isolation and de-energisation. Personal protective equipment and signage are lower-order controls used when the hazard cannot be eliminated.

Question 7Electrotechnology (Stage 6 VET Board Endorsed Course)

What does the term 'current-carrying capacity' of a cable refer to?

  1. The maximum current the cable can carry continuously without exceeding its temperature rating Correct answer.
  2. The total length of cable permitted on a circuit
  3. The peak voltage the insulation can withstand
  4. The number of conductors contained in the cable

Explanation

Current-carrying capacity is the maximum continuous current a conductor can carry under stated installation conditions while staying within its rated temperature. Exceeding it causes overheating and insulation degradation.

Question 8Electrotechnology (Stage 6 VET Board Endorsed Course)

Why must electrical workers follow the tag-out and lock-out procedure when isolating a circuit?

  1. To measure the insulation resistance of the circuit
  2. To record the time spent on maintenance
  3. To prevent the circuit being re-energised by another person while work is in progress Correct answer.
  4. To satisfy the manufacturer's warranty conditions

Explanation

Lock-out and tag-out physically prevent others from restoring supply while a person is working on the isolated circuit. This protects the worker from electric shock caused by unexpected re-energisation.

Question 9Electrotechnology (Stage 6 VET Board Endorsed Course)

A resistor of 12 ohms carries a current of 0.5 A. What is the voltage across it?

  1. 0.04 V
  2. 24 V
  3. 6 V Correct answer.
  4. 12 V

Explanation

Ohm's law states that voltage equals current multiplied by resistance, so 0.5 A times 12 ohms gives 6 V. Dividing instead of multiplying, or omitting the decimal, produces the other answers.

Question 10Electrotechnology (Stage 6 VET Board Endorsed Course)

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

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

Explanation

For two resistors in parallel the total resistance is the product divided by the sum, so 6 times 3 divided by 9 gives 2 ohms. The result is always less than the smallest individual resistance, which confirms the calculation.

Question 11Electrotechnology (Stage 6 VET Board Endorsed Course)

A circuit has a power factor of 0.8 and draws 15 A at 240 V. What is the true power?

  1. 1800 W
  2. 2880 W Correct answer.
  3. 3600 W
  4. 4500 W

Explanation

True power equals voltage times current times power factor, so 240 times 15 times 0.8 gives 2880 W. Ignoring the power factor would overstate the real power consumed by the load.

Question 12Electrotechnology (Stage 6 VET Board Endorsed Course)

Why is a residual current device used in addition to a circuit breaker on a final subcircuit?

  1. It detects small earth leakage currents that a circuit breaker will not respond to Correct answer.
  2. It disconnects on overload current faster than a circuit breaker
  3. It replaces the need for an earthing system
  4. It reduces the voltage supplied to the circuit

Explanation

A residual current device monitors the balance between active and neutral current and trips on small earth leakage, protecting people from shock. A circuit breaker responds to overload and short-circuit current, not low-level leakage.

Question 13Electrotechnology (Stage 6 VET Board Endorsed Course)

A cable is installed in a ceiling space where the ambient temperature is significantly higher than the standard reference. What effect does this have on the cable's current-carrying capacity?

  1. Capacity doubles to compensate for the heat
  2. Capacity decreases because the cable reaches its temperature limit at a lower current Correct answer.
  3. Capacity increases because heat escapes more readily
  4. Capacity remains unchanged because only cable size matters

Explanation

Higher ambient temperature means the conductor starts closer to its maximum rated temperature, so less current is needed to reach the limit. Correction factors are applied to reduce the tabulated current-carrying capacity.

Question 14Electrotechnology (Stage 6 VET Board Endorsed Course)

What is the purpose of a voltage drop calculation for a final subcircuit?

  1. To determine the insulation resistance of the cable
  2. To calculate the prospective short-circuit current
  3. To confirm the load will receive adequate voltage at the point of use Correct answer.
  4. To select the colour of the switchboard indicator lamps

Explanation

Voltage drop calculations check that the voltage at the load stays within acceptable limits so equipment operates correctly. Excessive drop can cause motors to overheat and lamps to dim.

Question 15Electrotechnology (Stage 6 VET Board Endorsed Course)

Which test confirms that the protective earthing conductor of a final subcircuit has a continuous low-resistance path back to the main earthing terminal?

  1. Polarity test of the active conductor
  2. Prospective short-circuit current test
  3. Earth continuity test Correct answer.
  4. Insulation resistance test between active and neutral

Explanation

An earth continuity test measures the resistance of the protective earthing path from the point of use back to the main earthing terminal. A low reading confirms the fault-current path required for protective device operation.

Question 16Electrotechnology (Stage 6 VET Board Endorsed Course)

A worker is required to work near exposed live parts and cannot isolate the supply. What is the most appropriate control?

  1. Ask a colleague to watch from a distance
  2. Proceed quickly to minimise exposure time
  3. Use insulated tools and gloves with a documented risk assessment and supervision Correct answer.
  4. Turn off the main switch for the whole building without notice

Explanation

Where isolation is not practicable, the risk must be assessed and controlled with insulated tools, personal protective equipment, and supervision under a documented safe work method. Speed and observation alone do not reduce the electrical hazard.

Question 17Electrotechnology (Stage 6 VET Board Endorsed Course)

Which of the following best describes the role of a competent person in electrical work?

  1. A worker who owns their own tools
  2. Any worker who has completed a site induction
  3. A supervisor who holds a first-aid certificate
  4. A person with the training, qualification, and experience to perform the task safely Correct answer.

Explanation

Competency in electrical work requires a combination of formal training, recognised qualifications, and relevant experience so the person can identify hazards and perform the task safely. Induction, first aid, or tool ownership alone do not confer electrical competency.

Question 18Electrotechnology (Stage 6 VET Board Endorsed Course)

A single-phase circuit is protected by a 16 A circuit breaker and uses a cable with a tabulated current-carrying capacity of 20 A. What is the primary purpose of checking that the protective device rating does not exceed the cable capacity?

  1. To guarantee the circuit will never trip
  2. To reduce the cost of the installation
  3. To ensure the cable is protected against sustained overload current Correct answer.
  4. To increase the voltage available at the load

Explanation

The protective device must operate before the cable is damaged by sustained overload, so its rating must not exceed the cable's current-carrying capacity. This coordination protects the insulation and prevents fire risk.

Question 19Electrotechnology (Stage 6 VET Board Endorsed Course)

A three-phase 400 V motor draws a line current of 10 A at a power factor of 0.85. Using the relationship for balanced three-phase power, what is the approximate true power?

  1. 5889 W Correct answer.
  2. 6800 W
  3. 10200 W
  4. 3400 W

Explanation

Balanced three-phase true power equals the square root of three times line voltage times line current times power factor, giving approximately 1.732 times 400 times 10 times 0.85, or about 5889 W. Omitting the square root term or the power factor gives the other values.

Question 20Electrotechnology (Stage 6 VET Board Endorsed Course)

During an insulation resistance test on a new final subcircuit, the reading is well below the minimum acceptable value. Which condition is the most likely cause?

  1. The load is switched off at the point of use
  2. The test instrument battery is fully charged
  3. The circuit is correctly connected and the result is normal
  4. There is moisture, damage, or a low-resistance path between conductors or to earth Correct answer.

Explanation

A low insulation resistance reading indicates an unwanted conductive path, commonly caused by moisture ingress, cable damage, or a wiring error connecting conductors together or to earth. The circuit must be investigated and the fault rectified before energising.

Question 21Electrotechnology (Stage 6 VET Board Endorsed Course)

A cable is run through thermal insulation batts in a ceiling. Why must a derating factor be applied to its current-carrying capacity?

  1. The insulation changes the supply frequency
  2. The insulation restricts heat dissipation, causing the conductor to run hotter for a given current Correct answer.
  3. The insulation adds resistance to the conductor itself
  4. The insulation increases the mechanical load on the cable

Explanation

Thermal insulation traps heat around the cable so the conductor reaches its rated temperature at a lower current. Applying a derating factor ensures the cable is not overloaded under these installation conditions.

Question 22Electrotechnology (Stage 6 VET Board Endorsed Course)

A circuit has a total load of 3.6 kW at 240 V. Which standard circuit breaker rating would be the minimum suitable choice if the next standard sizes above the calculated current are 16 A and 20 A?

  1. 32 A
  2. 20 A
  3. 10 A
  4. 16 A Correct answer.

Explanation

The load current is 3600 divided by 240, which equals 15 A. The smallest standard rating that is not less than this current is 16 A, provided the cable capacity and other conditions are satisfied.

Question 23Electrotechnology (Stage 6 VET Board Endorsed Course)

An apprentice is asked to connect a new socket outlet to an existing circuit. Which sequence best reflects correct safe practice?

  1. Isolate and lock out, prove dead, connect, then restore supply and test Correct answer.
  2. Test the outlet first, then isolate and connect
  3. Isolate without proving dead, connect, and restore supply
  4. Connect the outlet live, then isolate to test it

Explanation

Safe practice requires isolating and locking out the circuit, proving the point of work is de-energised, completing the connection, and then restoring supply and verifying the installation by testing. Proving dead is essential before touching conductors.

Question 24Electrotechnology (Stage 6 VET Board Endorsed Course)

A residual current device rated at 30 mA protects a final subcircuit. What does the 30 mA value represent?

  1. The prospective short-circuit current at the outlet
  2. The rated residual operating current at which the device is designed to trip Correct answer.
  3. The insulation resistance value required for the circuit
  4. The maximum load current the circuit may carry

Explanation

The 30 mA figure is the rated residual operating current, the earth leakage level at which the device is intended to operate to protect people. It is not a load rating or an insulation value.

Question 25Electrotechnology (Stage 6 VET Board Endorsed Course)

Which document sets out the minimum requirements for the safe installation and maintenance of electrical installations in Australia and New Zealand?

  1. AS/NZS 4836, safe electrical work
  2. AS 1674, welding safety
  3. AS/NZS 3000, the Wiring Rules Correct answer.
  4. AS/NZS 3760, in-service testing

Explanation

AS/NZS 3000 is the joint Australian/New Zealand Wiring Rules and provides the minimum mandatory requirements for the design, selection, installation and verification of electrical installations. Other standards such as AS/NZS 3760 and AS/NZS 4836 deal with in-service testing and safe working practices respectively, not general installation design.

Question 26Electrotechnology (Stage 6 VET Board Endorsed Course)

Which of the following is the standard colour used for the active conductor in a single-phase flexible cord in Australia?

  1. Brown Correct answer.
  2. Green/yellow
  3. Black
  4. Blue

Explanation

In Australian single-phase flexible cords, brown identifies the active, blue identifies the neutral and green/yellow identifies the protective earth. Black is used for the active in fixed wiring, not flexible cord.

Question 27Electrotechnology (Stage 6 VET Board Endorsed Course)

What is the primary purpose of an electrical switchboard schedule?

  1. To record the price of each installed circuit breaker
  2. To show the earth resistance of the installation
  3. To document the apprentice's training progress
  4. To list each circuit, its rating, purpose and protective device Correct answer.

Explanation

A switchboard schedule identifies each circuit by number, rating, purpose and the protective device that protects it. This allows a worker to isolate the correct circuit safely and assists future maintenance and fault finding.

Question 28Electrotechnology (Stage 6 VET Board Endorsed Course)

Which instrument is used to measure the resistance of a protective earth conductor during verification of a final subcircuit?

  1. Insulation resistance tester
  2. Voltage tester
  3. Clamp meter
  4. Low-resistance ohmmeter Correct answer.

Explanation

A low-resistance ohmmeter passes a test current through the conductor to measure its continuity and resistance accurately. A standard multimeter may not supply sufficient current to detect a poor connection reliably.

Question 29Electrotechnology (Stage 6 VET Board Endorsed Course)

What is the function of a fuse in an electrical circuit?

  1. To provide a low-impedance path to earth during a fault
  2. To interrupt the circuit when current exceeds a set value Correct answer.
  3. To improve the power factor of the load
  4. To reduce the voltage supplied to the load

Explanation

A fuse contains a fusible element that melts when the current exceeds its rating, opening the circuit and protecting conductors and equipment from overcurrent. It does not regulate voltage or power factor.

Question 30Electrotechnology (Stage 6 VET Board Endorsed Course)

Which of the following best describes the meaning of the term 'extra-low voltage' in an electrical installation?

  1. A voltage exceeding 1000 V AC
  2. A voltage between 50 V and 1000 V AC
  3. A voltage not exceeding 50 V AC or 120 V ripple-free DC Correct answer.
  4. A voltage equal to the supply voltage of the premises

Explanation

Extra-low voltage is defined as a voltage not exceeding 50 V AC or 120 V ripple-free DC. Voltages above extra-low but not exceeding 1000 V AC are classified as low voltage.

Question 31Electrotechnology (Stage 6 VET Board Endorsed Course)

Which personal protective equipment is specifically required when working with energised low-voltage equipment that cannot be isolated?

  1. Insulating gloves rated for the voltage Correct answer.
  2. Leather work gloves
  3. Safety glasses only
  4. Cotton overalls

Explanation

When live work is unavoidable, insulating gloves rated for the working voltage provide a barrier against electric shock. Ordinary leather or cotton items do not provide electrical insulation.

Question 32Electrotechnology (Stage 6 VET Board Endorsed Course)

What does the term 'single point of isolation' mean in electrical work?

  1. Isolating the installation at one point that removes supply from all relevant circuits Correct answer.
  2. Isolating each circuit at every outlet
  3. Isolating the neutral conductor only
  4. Isolating the circuit using a switch that is not lockable

Explanation

Single point of isolation means the supply is removed at one point, such as the main switch, so that all circuits to be worked on are de-energised. This simplifies isolation and reduces the risk of accidentally leaving a circuit energised.

Question 33Electrotechnology (Stage 6 VET Board Endorsed Course)

A 12 V lamp has a resistance of 24 ohms. What current flows through the lamp?

  1. 0.5 A Correct answer.
  2. 2.0 A
  3. 0.05 A
  4. 288 A

Explanation

Ohm's law gives current as voltage divided by resistance, so 12 V divided by 24 ohms equals 0.5 A. The value is obtained by dividing, not multiplying, the given quantities.

Question 34Electrotechnology (Stage 6 VET Board Endorsed Course)

Three resistors of 2 ohms, 4 ohms and 6 ohms are connected in series across a 24 V supply. What is the voltage across the 6 ohm resistor?

  1. 24 V
  2. 8 V
  3. 12 V Correct answer.
  4. 4 V

Explanation

The total resistance is 12 ohms, so the circuit current is 24 V divided by 12 ohms, which is 2 A. The voltage across the 6 ohm resistor is 2 A multiplied by 6 ohms, giving 12 V.

Question 35Electrotechnology (Stage 6 VET Board Endorsed Course)

A 240 V single-phase appliance draws 8 A and has a power factor of 0.75. What is the apparent power drawn by the appliance?

  1. 1920 VA Correct answer.
  2. 1080 W
  3. 2560 VA
  4. 1440 VA

Explanation

Apparent power is voltage multiplied by current, so 240 V times 8 A equals 1920 VA. Power factor is used to find true power, not apparent power.

Question 36Electrotechnology (Stage 6 VET Board Endorsed Course)

A circuit has a true power of 2.4 kW and an apparent power of 3.0 kVA. What is the power factor?

  1. 0.8 Correct answer.
  2. 1.25
  3. 0.75
  4. 0.6

Explanation

Power factor is true power divided by apparent power, so 2.4 divided by 3.0 equals 0.8. A power factor must be between zero and one for a passive load.

Question 37Electrotechnology (Stage 6 VET Board Endorsed Course)

A 400 V three-phase balanced load draws a line current of 20 A at unity power factor. What is the total power drawn?

  1. 4.6 kW
  2. 8 kW
  3. 13.9 kW Correct answer.
  4. 24 kW

Explanation

For a balanced three-phase load, power equals the square root of three multiplied by line voltage, line current and power factor. This gives 1.732 times 400 times 20 times 1, which is approximately 13.9 kW.

Question 38Electrotechnology (Stage 6 VET Board Endorsed Course)

A final subcircuit has a calculated voltage drop of 9 V on a 240 V supply. What percentage voltage drop does this represent?

  1. 2.7 %
  2. 3.75 % Correct answer.
  3. 9 %
  4. 0.375 %

Explanation

Percentage voltage drop is the drop divided by the supply voltage, multiplied by 100. Nine volts divided by 240 V gives 0.0375, which is 3.75 %.

Question 39Electrotechnology (Stage 6 VET Board Endorsed Course)

A cable has a tabulated current-carrying capacity of 30 A and is subject to a derating factor of 0.8 for ambient temperature. What is the effective current-carrying capacity?

  1. 24 A Correct answer.
  2. 30.8 A
  3. 22 A
  4. 37.5 A

Explanation

Derating factors are multiplied by the tabulated capacity, so 30 A times 0.8 gives 24 A. This reduced value must be at least equal to the design current for the circuit.

Question 40Electrotechnology (Stage 6 VET Board Endorsed Course)

A 240 V single-phase circuit draws 15 A. What is the minimum standard circuit breaker rating that can protect it?

  1. 32 A
  2. 10 A
  3. 20 A
  4. 16 A Correct answer.

Explanation

The protective device rating must be at least equal to the design current of 15 A. The next standard rating above 15 A is 16 A, provided the cable capacity is adequate.

Question 41Electrotechnology (Stage 6 VET Board Endorsed Course)

Why is a switch required to be connected in the active conductor rather than the neutral conductor?

  1. To improve the earth fault loop impedance
  2. To allow the neutral to be used as an earth return
  3. To reduce the current drawn by the circuit
  4. To ensure the load is de-energised when the switch is open Correct answer.

Explanation

Switching the active removes the supply potential from the load so that it is safe to work on when the switch is open. A neutral-switched circuit leaves the load connected to the active and therefore still energised.

Question 42Electrotechnology (Stage 6 VET Board Endorsed Course)

A residual current device with a rated residual current of 30 mA is installed on a final subcircuit. What does this value indicate?

  1. The voltage at which the device resets automatically
  2. The insulation resistance of the protected circuit
  3. The current imbalance at which the device is intended to operate Correct answer.
  4. The maximum load current the circuit may carry

Explanation

The rated residual current is the leakage current imbalance to earth at which the RCD is designed to trip. A 30 mA device provides additional protection against electric shock by operating at low leakage levels.

Question 43Electrotechnology (Stage 6 VET Board Endorsed Course)

During a fault, the earth fault loop impedance is measured as 1.5 ohms on a 240 V circuit. What fault current would flow, ignoring other impedances?

  1. 160 A Correct answer.
  2. 360 A
  3. 16 A
  4. 36 A

Explanation

The prospective earth fault current is the supply voltage divided by the earth fault loop impedance. Dividing 240 V by 1.5 ohms gives 160 A, which must be sufficient to operate the protective device within the required time.

Question 44Electrotechnology (Stage 6 VET Board Endorsed Course)

Which of the following is the most appropriate action before commencing work on a circuit that has been isolated and locked out?

  1. Check that the light switch is in the off position
  2. Assume the circuit is safe because the breaker is off
  3. Test the circuit for the absence of voltage at the point of work Correct answer.
  4. Ask a workmate whether the circuit is off

Explanation

After isolation and lock-out, the circuit must be proved de-energised by testing for the absence of voltage at the point of work with a suitable tester. Assumptions or second-hand information are not acceptable verification.

Question 45Electrotechnology (Stage 6 VET Board Endorsed Course)

A single-phase motor has a full-load current of 12 A and a starting current of six times full load. Which protective device characteristic is most suitable for this motor circuit?

  1. A device with no overload protection at all
  2. A device with a delayed overload characteristic to ride through starting current Correct answer.
  3. A device with an instantaneous trip at 12 A
  4. A device with a rating below the full-load current

Explanation

Motor starting currents are several times full load and last briefly, so the protective device must tolerate this inrush without tripping. A delayed overload characteristic provides this while still protecting against sustained overloads.

Question 46Electrotechnology (Stage 6 VET Board Endorsed Course)

A circuit is protected by a 20 A circuit breaker but the connected cable has a current-carrying capacity of 16 A. What is the main risk of this arrangement?

  1. The earth fault loop impedance will increase
  2. The circuit breaker will trip too often during normal operation
  3. The cable may overheat before the breaker operates Correct answer.
  4. The voltage drop will be too low for the load

Explanation

The protective device must not allow a sustained current greater than the cable's capacity, otherwise the cable can overheat and its insulation may be damaged. Coordination requires the device rating to be no greater than the cable capacity after derating.

Question 47Electrotechnology (Stage 6 VET Board Endorsed Course)

Which of the following is the correct sequence for safe isolation of an electrical circuit before maintenance?

  1. Test for dead, isolate, work, then lock and tag
  2. Isolate, work, then test for dead
  3. Lock and tag, work, then isolate
  4. Identify, isolate, lock and tag, test for dead, then work Correct answer.

Explanation

Safe isolation follows a defined sequence: identify the circuit, isolate the supply, secure with lock and tag, then prove the circuit de-energised by testing before work begins. Working before testing or securing isolation risks contact with live parts.

Question 48Electrotechnology (Stage 6 VET Board Endorsed Course)

An insulation resistance test on a new 230/400 V final subcircuit returns a value of 0.5 megohm. How should this result be interpreted?

  1. The result is normal for a new installation
  2. The result is below the minimum requirement and the circuit requires investigation Correct answer.
  3. The result is acceptable because any reading above zero is satisfactory
  4. The result is too high and indicates a short circuit

Explanation

Insulation resistance for a low-voltage installation must meet the minimum value specified in the Wiring Rules, typically 1 megohm for the whole installation. A reading of 0.5 megohm is below this minimum and indicates moisture, damage or a faulty component that must be located and rectified.

Question 49Electrotechnology (Stage 6 VET Board Endorsed Course)

Which of the following best explains why an equipotential bonding conductor is installed between metallic water pipes and the main earthing terminal?

  1. To reduce the power consumed by the installation
  2. To keep exposed and extraneous conductive parts at a similar potential Correct answer.
  3. To increase the current-carrying capacity of the active conductor
  4. To carry the normal load current of the installation

Explanation

Equipotential bonding connects extraneous conductive parts to the earthing system so that they remain at a similar potential during a fault. This minimises the voltage difference a person could contact and reduces shock risk.

Question 50Electrotechnology (Stage 6 VET Board Endorsed Course)

Which document type provides the minimum legal requirements for electrical installation work in Australia and is given legal force through state and territory legislation?

  1. An Australian/New Zealand Standard
  2. A workplace safe work method statement
  3. A manufacturer's installation instruction
  4. An Act of Parliament with accompanying Regulations Correct answer.

Explanation

Legislation, meaning Acts and the Regulations made under them, creates legally enforceable duties, while Standards such as AS/NZS 3000 are only given legal effect when a Regulation or other instrument calls them up. A Standard on its own is a consensus technical document and is not law.