AS 3851-1991
Current
The latest, up-to-date edition.
The calculation of short-circuit currents in three-phase a.c. systems (Reconfirmed 2015)
Hardcopy , PDF 1 User , PDF 3 Users , PDF 5 Users , PDF 9 Users
13-05-1991
Important note : Users cannot be edited or removed once added to your Multi user PDF.Specifies standard methods for the calculation of short-circuit currents in three-phase a.c. systems, both radial and meshed with and without contribution from generators and motors, which are suitable for either computer or manual calculation.
| Committee |
EL/7
|
| DocumentType |
Standard
|
| ISBN |
0 7262 6515 2
|
| Pages |
88
|
| ProductNote |
Reconfirmed 18/05/2015.This standard as been reconfirmed in Australia in 2015 and remains current in New Zealand. Reconfirmation Notice 18/05/2015
|
| PublisherName |
Standards Australia
|
| Status |
Current
|
| Supersedes |
This Standard specifies a standardized procedure for the calculation of prospective short-circuit currents in the fault for-(a) low voltage a.c. systems; and (b) high voltage three-phase a.c. systems, operating at a nominal frequency of 50 Hz.The procedure is intended to be, as far as possible, in a form to facilitate its use by non-specialist engineers.NOTE: The procedure is applicable generally to other frequencies close to 50 Hz; however, care should be exercised in the use of frequency-dependent factors.Except in Appendix A, the basis of the calculation procedure in this Standard is ohmic. Appendix A converts this procedure to per-unit calculation.NOTE: Worked examples are provided in Appendices D and E on ohmic and per unit basis respectively.The current, calculated in this Standard forms the basis for the determination of the currents in the paths feeding the fault.This Standard specifies a standardized method for the calculation of the joule integral (I2t) of a short-circuit current.This Standard does not cover-(i) short-circuits deliberately created under controlled conditions as in short-circuit testing stations; (ii) short-circuits in the electrical installations of ships and aircraft; (iii) non-simultaneous short-circuits, which can lead to higher aperiodic components of short-circuit current; or (iv) methods for analysis of short-circuit currents in non-linear systems.
First published as AS 3851-1991.
Incorporating: Amdt 1-1992
| AS 1824.1-1995 | Insulation co-ordination Definitions, principles and rules |
| AS 2926-1987 | Standard voltages - Alternating (50 Hz) and direct |
| AS 2374.1-1997 | Power transformers General |
| AS 3008.1-1989 | Electrical installations - Selection of cables - Cables for alternating voltages up to and including 0.6/1 kV |
| AS/NZS 3439.2:2002 | Low-voltage switchgear and controlgear assemblies Particular requirements for busbar trunking systems (busways) |
| AS 2374.8-2000 | Power transformers Application guide (Reconfirmed 2016) (Reconfirmed 2024) |
| AS 2067-2008 | Substations and high voltage installations exceeding 1 kV a.c. |
| AS 3865-1991 | Calculation of the effects of short-circuit currents |
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