AT4 Flashcards
Protection can be afforded to both basic protection and fault protection with the use of?
A: Class 2 equipment
B: RCDS
C: Extra Low Voltage
C: extra low voltage
Clause 1.5.7
A final sub circuit supplying a single phase 8kW stove is supplied by a 6mm2 twin and earth cable, and is protected by a circuit breaker only. What is likely to occur if the protective earthing conductor is transposed with the neutral conductor and the fault is next detected
A: the final sub-circuit breaker will operate
B: no dangerous condition would exist
C: the electric stove will not operate correctly
D: the protective earthing conductor would likely overheat
D: the protective earthing conductor would likely overheat
The maximum resistance of an earth conductor accompanying a sub-mains circuit shall be:
A: less than or equal to 0.5 ohms
B: less than or equal to 2 ohms
C: less than or equal to 1 mega ohm
D: low enough to permit the passage of current necessary to operate the overcurrent protective device
D: low enough to permit the passage of current necessary to operate the overcurrent protective device
What is the maximum earth continuity reading for equipotential bonding of showers, bathrooms, swimming and spa pools?
Must not be greater than 0.5 ohms
State four methods of protection for direct contact with live parts, as stated in AS/NZS 3000 and give an example of each.
Insulation - cable insulation
Barriers - fences around transformers
Obstacles - key to the switchboard
Placing out of reach - overhead mains and power lines
State four methods to protection for indirect contact with live parts, as stated in AS/NZS 3000 and give an example of each
Automatic disconnection of supply - fuse or circuit breaker (RCD is supplementary)
Use of class 2 equipment - double insulated equipment
Separation of the system - isolating transformer
Limit to lower than shock current - RCD
Name four external influences which must be considered when selecting and installing electrical equipment, also, please provide the relevant clause
Clause 4.1.3
Mechanical damage
Weather
Water
Flora
Fauna
Excessive dampness
Corrosive fumes
Galvanic fumes
Accumulation of dust or solid foreign bodies
Steam
Oil
Temperature
Solar radiation
Vibration
Seismic activity
If a word or term is not in the definition section of AS/NZS 3000, how should that word or term be interpreted when reading the AS/NZS 3000? Please provide clause number
The commonly understood meaning applies
Clause 1.4.1
Match the following terms to the principle
A = caused by electrically actuated equipment
B = compliance with part 2 of AS/NZS 3000 is deemed to comply with part 1
C = can be induced in unused conductors
D = installations be inspected and tested
E = ignition of adjacent material
Abnormal voltages =
Spread of fire =
Injury from mechanical movement =
Means of compliance =
Verification of compliance =
Abnormal voltages = C
Spread of fire = E
Injury from mechanical movement = A
Means of compliance = B
Verification of compliance = D
What are the requirements for dealing with unused conductors? Also, please provide the relevant clause
Shall be terminated as for live conductors
1.5.11.4
A light switch is to be installed, at a height of 1.2m, on a wall where high pressure hosing is carried out. What degree of protection is required for this switch to comply with the AS/NZS 3000
IPX6
6.7.4.1
Select the appropriate minimum IP rated socket outlet, for a pool filter that has been installed 2.2m from the pool edge, at a height of 500mm. Also, please provide the relevant clause.
A = IPX3
B = IPX4
C = IPX5
D = IPX6
B = IPX4
6.3.4.1 or table 6.2
Name three means of electrical protection for a socket outlet mounted in zone 3 in a bathroom
RCD, SELV, PELV, separated circuit
Name two areas that AS/NZS 3000 defines as being ‘damp situations’, also, please provide the relevant clause
Baths, showers and other fixed water containers
Swimming pools, paddling pools and spa pools or tubs
Fountains and water features
Saunas
Refrigeration rooms
Sanitisation and general hosing operations
What are the two types of areas classified as a hazardous area if electrical equipment is to be installed? Also, please provide in the relevant clause
The presence of combustible dust or an explosive gas or vapour
AS/NZS 3000 7.7.2.2
If working on equipment in hazardous areas what additional training would you require?
Hazardous area training
Electrical equipment selected for use in hazardous areas shall comply with the applicable requirements for which standard
AS/NZS 60079.14
For insulated aerial cables, the minimum height above areas used by vehicles is:
A = 3m
B = 4.6m
C = 5.5m
D = not allowed
B = 4.6m
Clause table 3.8
Aerial wiring systems shall be of the following four types. Use the AS/NZS to complete the following
A.
B.
C.
D.
A = hard drawn bare conductors
B = polymeric insulated cables
C = neutral screened cables
D = parallel-webbed, twisted or bundled insulated cables
Where in the AS/NZS 3000 does it outline the minimum sizes of posts, poles and struts for aerial line conductors
Appendix D
AS/NZS 3000 outlines the requirements for the characteristics of catenary supports. Which of the following statements is incorrect
A) provide uniform support
B) Be effectively fixed at each end
C) Be capable of withstanding mechanical stress
D) provide uniform electrical integrity
A) provide uniform support
If category A underground wiring systems shall is being used external to a building in a location that has no surface covering. What is the minimum depth of cover? Please provide relevant clause
Depth: 500mm
AS/NZS table 3.6
What is the minimum separation of underground wiring to underground services
Gas = ?
Sanitary drainage = ?
Water service greater than DN65 = ?
Telecommunications = ?
Gas = 100mm
Sanitary drainage = 100mm
Water service greater than DN65 = 300mm
Telecommunications = 100mm
What AS/NZS 3000 clause outlines the requirements for the fundamental principle for selection and installation of equipment?
AS/NZS clause 1.7.1
What AS/NZS 3000 clause outlines the requirements for the fundamental principle for installation design?
AS/NZS 3000 clause 1.6.1
When terminating a consumes mains cable what are the maximum size cables for the following:
Mains connection box:
To the residential service pillar fuse:
Mains connection box: 95mm2
To the residential service pillar fuse: 35mm2
When terminating consumers mains cables in underground pits what environmental conditions do you need to protect from?
Ingress of water
