BS EN 61439-6:2012 Low-voltage switchgear and controlgear assemblies Part 6: Busbar trunking systems (busways)

BS EN 61439-6:2012 pdf free download.Low-voltage switchgear and controlgear assemblies Part 6: Busbar trunking systems (busways).
This clause of Part 1 is applicable except as follows. Additional definitions:
3.101 busbar trunking system BTS busway enclosed ASSEMBLY used to distribute and control electrical energy for all types of loads, intended for industrial, commercial and similar applications, in the form of a conductor system comprising busbars which are spaced and supported by insulating material in a duct, trough or similar enclosure
[SOURCE: IEC 60050-441 :1984. 441-12-07 modifiedj
Note ito entry: See 3.1.1 of Part 1 for the definition of ASSEMBLY.
Note 2 to entry; The BTS may consist of a full range of mechanical and electrical components such as;
— busbar trunking units with or without tap-off facilities;
— phase transposition, expansion, flexible, feeder and adapter units:
— tap-off units;
— addilional conductors for communication and/or control.
Note 3 to entry: The term busbar” does not presuppose the geometrical shape, size and dimensions of the conductor.
3.102 busbar trunking unit BTU unit of a BTS complete with busbars. their supports and insulation, external enclosure and any fixing and connecting means to other units, with or without tap-off facilities
Note I to entry: BTU5 may have different geometrical shapes such as straight length, elbow, tee or cross.
3.103 busbar trunking run BT run
number of BTUs connected together to form the BTS, excluding the tap-off units
3.104 busbar trunking unit with tap-off facilities BTU with tap-off facilities BTU designed to enable tap-off units to be installed at one or more points as predetermined by the original manufacturer
4 Symbols and abbreviations
This clause of Part 1 is applicable except as follows.
5 Interface characteristics
This clause of Part us applicable except as follows,
5.1 General
Replacement:
The characteristics of the BTS shall ensure compatibility with the ratings of the circuits to which it is connected and the installation conditions and shall be declared by the BTS manufacturer using the criteria identified in 5.2 to 5.6 and 5.101 to 5.102.
The specification schedule according to informative Annex C is intended to help the user and the BTS manufacturer to meet this objective, whether the user:
• select catalogue products the characteristics of which meet their needs, and the requirements of this standard,
• andlor make a specific agreement with the manufacturer.
NOTE Annex C also relates to the topics dealt with in Clauses 6 and 7.
In some cases information provided by the BTS manufacturer may take the place of an
agreement.
5.2.4 Rated impulse withstand voltage (Uimp) (of the ASSEMBLY)
Replacement of the NOTE:
NOTE Unless otherwise specified, the rated impulse withstand voltage is selected according to overvoltage category IV (origin of installation level) or Ill (distribution circuit level) as given in Table G.1 of Part 1.
5.3.1 Rated current of the ASSEMBLY (mA)
Addition:
NOTE 4 Where the BTS is not equipped with a single incoming unit at one end of the BT run. (e.g. incoming unit not installed at one end of the BTS, or more than one incoming unit), the rated currents will be subject to agreement between the user and the manufacturer.
The rated current shall apply for a specified mounting orientation (see 5.3.2). However the influence of the mounting orientation may be ignored for short (e.g. less than 3 m long) vertical sections in a horizontal BTS.
The BTS manufacturer may state the rated currents of the BTS for different ambient temperatures for example by means of the following formula:
where kiA is a temperature factor, equal to 1 at an ambient air temperature of 35 °C.
In case of significant harmonic currents, special agreement shall be made for a reduction factor, if necessary.
5.3.2 Rated current of a circuit
Addition:
The rated current (‘) of each circuit (i.e. incoming unit, BTU, tap-off unit, outgoing circuit) shall be equal to or higher than its assumed loading. For tap-off units provided with more than one main outgoing circuit, see also 5.4.
The rated current shall apply for specified mounting conditions. Mounting conditions may include orientation and position, as follows:
a) orientation
Orientation may be horizontal or vertical.
Unless otherwise specified, the reference orientation is horizontal.
b) position
Position may be for example edgewise or flatwise for a BT run, and/or below or on top of the BTU for a tap-off unit.
The BTS manufacturer may state different rated currents for different ambient temperatures and/or mounting conditions, where applicable, for example by means of the following formula:
= k k2 1 where
is a temperature factor, equal to 1 at an ambient air temperature of 35 C; k2c is a mounting factor, equal to 1 in the reference mounting conditions.
In case of significant harmonic currents, special agreement shall be made for a reduction factor, if necessary.
5.4 Rated diversity factor (RDF)
Replacement:
For the whole BTS. unless otherwise specified, the RDF (see 3.8.11 of Part 1) shall be equal to 1, I.e. all tap-off units can be continuously and simultaneously loaded with their full rated current, within the limit of the rated current of the BT run(s) and feeder BTU(s)
NOTE 1 This is because thermal influence between tap-off units is considered negligible.
For tap-off units provided with more than one main outgoing circuit, these circuits shall be
able to be continuously and simultaneously loaded at their rated current multiplied by the
RDF, within the limit of the rated current of the tap-off unit. Unless otherwise specified, the
RDF of such tap-off units shall be equal to the values given in Table 101.
5.102 Electromagnetic field
The strength of the power frequency magnetic field in the vicinity of the BT run may be stated
by the BTS manufacturer.
NOTE The magnetic field is a fast-decreasing function of the distance.
A method for measurement and calculation of the modulus of the magnetic field around the BTS is given in Annex EE.
6 Information
This clause of Part 1 is applicable except as follows.
6.1 ASSEMBLY designation marking Addition after the first paragraph:
One nameplate shall be located near one end of each BTU and one on each tap-off unit.
Replacement:
d) IEC 61439-6.
7 Service conditions
This clause of Part 1 is applicable except as follows.
7.2 Special service conditions
Addition:
aa) exposure to special mechanical loads, such as lighting apparatus, additional cables. ladder supports, etc.;
bb) applications with high repetitive overcurrent, for example resistance welding;
cc) installation near highly sensitive IT equipment, such as high-speed data networks, radiology apparatus, workstation monitors, etc.;BS EN 61439-6 pdf download.BS EN 61439-6:2012 Low-voltage switchgear and controlgear assemblies Part 6: Busbar trunking systems (busways)BS EN 61439-6:2012 Low-voltage switchgear and controlgear assemblies Part 6: Busbar trunking systems (busways)