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Fully charged Fig 2 Minimum width of gangway (to be read with Table 1)
Table 1 Gangway minimum width and height above Gangway characteristic
Minimum applicable dimension (mm)
Gangway width including between: • barriers or enclosures (or obstacles, where applicable) and switch handles in their most onerous position, and • barriers or enclosures (or obstacles, where applicable) or switch handles in their most onerous position and the wall
700 (see Fig 2)
Gangway width between barriers or enclosures (or obstacles, where applicable) and other barriers or enclosures (or obstacles, where applicable) and the wall
700 (see Fig 2)
Height of barrier or enclosure (or obstacle, where applicable), measured from gangway floor
2000
Height of Iive parts placed out of reach (Regulation 417.3), measured from gangway floor
2500
Notes. 1) This table gives only a summary of the relevant requirements. For the full requirements, see BS 7671, Section 729. 2) Larger dimensions may be required for particular items of switchgear or controlgear (including for transport of these). 3) See Fig 3 regarding provision of space to permit 90° opening of equipment access doors or hinged panels. 4) The use of obstacles is permitted only for parts of the installation that are controlled or supervised by skilled persons (Regulations 417.1 and 729.513.2.2 refer). Obstacles are therefore unsuitable for use where an instructed person not under the supervision of a skilled person is authorised to access an area.
situations are given in Fig 729.3 of the regulation. The main evacuation requirements in Annex A729 can be summarised as: • doors of equipment must close in the direction of the evacuation route • gangways must permit at least 90° opening of equipment access doors or hinged panels • doors that can be fixed in the open position and circuit-breakers that are fully withdrawn for maintenance require at least 500 mm clearance to the opposite limitation of the gangway when the door is open or the circuit-breakers fully withdrawn (see Fig 3). Where items of switchgear or controlgear are installed face to face, it is important that if equipment doors need to be opened, or circuit-breakers need to be withdrawn, opposite each other, at least the minimum passing width shown in Fig 3 is available with doors fully open/circuitbreakers fully withdrawn.
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Summer 2012 NICEIC Connections
51_52_technical 2 operating.CC2.indd Sec2:52
Barriers or enclosures
Circuit-breaker in the position “isolation”
700 mm
700 mm
Elevation view
Fig 3 Minimum passing width (for evacuation) allowing for 90° opening of access doors and withdrawal of circuit-breakers
Plan view
Minimum passing width 500 mm*
1
2
1
Circuit-breaker in the position “completely extracted”
2
Fixing device of a door
*
The minimum width of a gangway of 500 mm shall be taken into consideration between the wall and the circuit-breaker in the position “completely extracted” and equipment door in the 90 degree position
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26/06/2012 14:33