Capstone - Max Demand Flashcards
AS/NZS 3000 clause 2.2.2 states which four acceptable methods that are acceptable to determine max demand?
1 - Calculation
2 - Assessment
3 - Measurement
4 - Limitation
Which appendix of the AS/NZS 3000 will assist with calculating max demand?
Appendix C
Which table is used for calculating single and domestic max demand?
Table C1
Which table is used for calculating non-domestic installations?
Table C2
Which table is used for calculating final sub-circuits?
Table C9
What steps should you take when calculating max demand?
1 - Divide into load groups
2 - Distribute across phases
3 - Perform calculations per phase
4 - Total each phase
5 - Check balance
The relationship between operating characteristics of a protective device and a conductor against overload is known as what?
Coordination
IB ≤ IN ≤ IZ refers to which type of protective device?
Circuit breaker
IB ≤ IN ≤ 0.9 x IZ refers to which type of protective device?
HRC fuse
The 0.9 derating factor when using an HRC fuse applies to the CCC of the cable, True or False?
False
Which standard is used to calculate current carrying capacity for cable selection?
AS/NZS 3008
Which version of the AS/NZS 3008 is used in Australia?
1.1
What is the default Ambient Air and Soil temperatures used in Australia?
Air - 40C, Soil - 25C
What is the definition of current carrying capacity?
Maximum continuous current that a cable may carry without exceeding it’s maximum permissible temperature
What characteristic produces heat in a conductor when it is carrying current?
Resistance
Which de-rating tables are used for grouping of cables?
T22-26
Which de-rating table is used for ambient temperature?
T27
Which de-rating table is used for depth of cables?
T28
Which de-rating table is used for resistivity of soil?
T29
Current carrying capacity must be (greater than, less than) the maximum demand of the circuit.
Greater than
Tables 3.1-3.4 are used to determine what information?
Installation method
Tables 16 & 17 are used in relation to which type of cable?
Flexible cord that is not fixed wiring
Tables 18 & 19 are used in relation to which type of cable?
MIMS
Tables 20 & 21 are used in relation to which type of cable?
Aerial
Tables 4-15 are used in relation to which type of cable?
Thermoplastic / XLPE
What is the standard depth of burial for cable?
500mm
When multiple de-rating factors apply to determine cable current carrying capacity, you may use only the one which has the highest de-rating to satisfy the standard - True or False?
False - all de-rating factors apply by compounding
