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PD 7639-2:1994

Superseded
Superseded

A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.

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superseded

A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.

Short-circuit current calculation in three-phase a.c. systems Data for electrical equipment for short-circuit current calculations in accordance with BS 7639
Available format(s)

Hardcopy , PDF

Superseded date

31-01-2009

Language(s)

English

Published date

15-04-1994

Committees responsible
National foreword
Section 1. General
1.1 Scope and object
1.2 Reference documents
Section 2. Data for electrical equipment
2.1 General
2.2 Data on typical synchronous machines
2.3 Data on typical transformers, two-winding, three-
     winding and auto-transformers
2.4 Data on typical overhead lines, single and double
     circuits
2.5 Data on typical low- and high-voltage cables
2.6 Data on typical asynchronous motors
2.7 Busbars
Tables
1 Information received from National Committees
2 Actual data of typical synchronous generators,
     condensers and motors
3A Actual data of typical two-winding transformers
3B Actual data of typical three-winding transformers
3C Actual data of typical autotransformers with and
     without tertiary winding
4 Actual data of typical overhead lines (single and
     double circuit 50 and 60 Hz) per circuit
5 Actual data of typical electric cables
6 Actual data of typical asynchronous motors
7 Actual data of distribution busbar
Figures
1 Subtransient reactance of synchronous machines
     (motors SM, condensers SC, turbogenerators and
     salient pole generators) 50 Hz and 60 Hz
2 Rated voltage UrG and rated power factor cos phi rG
     of synchronous machines (motors, condensers,
     turbogenerators and salient pole generators) 50 Hz
     and 60 Hz
3 Unsaturated and saturated synchronous reactances of
     two-pole turbogenerators 50 Hz (n = 3 000 /min)
     and 60 Hz (n = 3 600 /min)
4 Rated short-circuit voltage ukr of power station
     generator transformers (PT) with or without tap-
     changer
5 Rated short-circuit voltage ukr of network
     transformers
6 Positive-sequence reactance X'(1)L of low-voltage
     and medium-voltage overhead lines 50 Hz, Cu or Al
7 Positive-sequence reactance X'(1)L of overhead
     lines 50 Hz
8 Type of line
9 Positive-sequence reactance X'(1) of low-voltage
     cables Cu or Al, 50 Hz (Germany)
10 Positive-sequence reactance X'(1) of medium-voltage
     cables, 50 Hz
11 Low-voltage cables 0,6/1kV, positive-sequence
     reactance X'(1) and ratios R(0)/R(1) and X(0)/X(1).
     Copper conductors and return circuits a, b, c, d
12 Low-voltage cables 0,6/1kV, positive-sequence
     reactance X'(1) and ratios R(0)/R(1) and X(0)/X(1).
     Aluminium conductors and return circuits a, b, c, d
13 Low-voltage cables 0,6/1kV, type A, with four
     conductors Cu or Al (Germany), R(0)/R(1) and
     X(0)/X(1)
14 Low-voltage cables 0,6/1kV, type A, with three and
     a half copper conductors (Germany), R(0)/R(1) and
     X(0)/X(1)
15 Low-voltage cables 0,6/1kV, type B, with four
     conductors Cu or Al and a concentric conductor Cu
     (Germany), R(0)/R(1) and X(0)/X(1)
16 Low-voltage cables 0,6/1kV, type B, with three
     conductors Cu or Al and a concentric conductor Cu
     (Germany), R(0)/R(1) and X(0)/X(1). The concentric
     conductor has the same cross-section as the main
     conductor
17 Low-voltage cables 0,6/1kV, type B, with three
     conductors Cu or Al and a concentric conductor Cu
     (Germany), R(0)/R(1) and X(0)/X(1). The concentric
     conductor has half the cross-section as the
     main conductor
18 Low-voltage cables 0,6/1kV, type C, with three
     conductors Cu or Al and aan aluminium sheath
     (Germany), R(0)/R(1) and X(0)/X(1)
19 Low-voltage cables 0,6/1kV, type D, with four
     conductors Cu or Al and a lead sheath with steel
     armouring (Germany), R(0)/R(1) and X(0)/X(1)
20 Low-voltage cables 0,6/1kV, type D, with three and
     a half conductors Cu or Al and a lead sheath with
     steel armouring (Germany), R(0)/R(1) and X(0)/X(1)
21 Locked-rotor currents ILR/IrM of low-voltage and
     medium-voltage asynchronous motors, 50 Hz and 60 Hz
22 Product cos phi rM.eta r of low-voltage and medium-
     voltage asynchronous motors, 50 Hz and 60 Hz

Comprises data collected from different countries to be used when necessary for calculating short-circuit currents in accordance with BS 7638:1993 and BS 7639:1994.

Committee
W/-
DocumentType
Standard
Pages
48
PublisherName
British Standards Institution
Status
Superseded
SupersededBy

BS 4727(1971) : LATEST
BS 7639:1993 Short-circuit current calculation in three-phase a.c. systems
BS 7638:1993 Application guide for calculation of short-circuit currents in low-voltage radial systems

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£262.00
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