TYPES OF SWITCHBOARD
2.1 TYPES OF SWITCHBOARD
The types of switchboard shall be as specified in the Bill of Quantities and/or Drawings and shall be of the following types: –
(a) Self-contained, floor mounted, flush fronted, metalclad cubicle type
suitable for front and rear access;
(b) Self-contained, floor mounted, flush fronted, metalclad cubicle type
suitable for front access;
(c) Pedestal, floor mounted, metalclad type suitable for front access;
(d) Wall mounted metalclad type suitable for front access.
The switchboards shall house their air circuit breakers, moulded case circuitbreakers, fuse switches, switch fuses, isolators, contactors, busbars, meters,protective relays, selector switches, indicating lamps, current transformers,cable terminating boxes, cable glands, anti-condensation heaters complete with automatic thermostats and isolators and all other necessary items of equipment whether specified hereinafter or in the Drawings or not, suitable for operation on a 415/240 V, 3 phase, 4 wire, 50 Hz. system with solidly earthed neutral.Unless otherwise specified elsewhere, the switchboards shall be capable of withstanding fault condition of not less than 50 kA at 415 V for 1 s as defined in IEC 60439-1. The degree of protection shall be IP42 for indoor installation and IP54 for outdoor installation in accordance to IEC 60529. The switchboards shall comply with IEC 60439-1 and outdoor switchboards shall also comply with IEC 60439-5. Routine tests on the switchboard shall be carried out before delivery to site.
The main circuits and the auxiliary circuits shall be tested to verify dielectric properties with power-frequency test voltage of 2500 Vac for 1 minute and insulation resistance under test voltage of 1000 V. Routine tests shall include inspection and checking of wiring, electrical continuity of the protective circuits, connections and effectiveness of mechanical actuating elements and interlock. Test Results or Certificate duly certified by Competent Person as in Electricity Regulations 1994 shall be issued for every switchboard supplied and installed.