The bus bars are divided into sections corresponding to the switchboard transport sections. At the joining position of the transport sections, mechanical bus connectors (screwed copper links) are installed. Earth bus bar is provided inside the panels for connecting the cable’s armour and grounding cables. They are fitted throughout the whole switchboard in conductive contact to the panel frame.

The phase mark of AC system is R-S-T (or U-V-W, L1-L2-L3), the bus bar is respectively distinguished with green-yellow-brown labels. The polarity identification of DC system is P-N, the bus bar is distinguished with red-blue labels. Earthing bar is marked with yellow/green label. The bus bar phase R-S-T and polarity P-N is arranged from left to right, top to below and front to rear.

1.1.6 Nameplates and labels

The manipulative and indicative components on the doors are distinctly marked by engraved nameplates, which are made of laminated PVC plate in flame retardant type, with black text on white background. For any nameplates used for emergency or warning purpose, white text on red All the nameplates are fastened by miniature screws.

For circuit breakers, the following information is marked on its nameplates:

- Item letter code number (identical to drawings and in accordance with IEC 750) - Service name (feeder designation or name of appliance) - Setting current / frame rated current (A)

In case of any feeder breakers equipped with emergency stop or preferential trip function, the colour coded labels are additionally added above its nameplate. For the distinguishing purpose, the colour identification nameplate will be accordingly arranged nearby.

The components located on the front doors such as change-over switches, measuring meters, pilot lamps & pushbuttons, are marked with item letter code number (identical to drawings and in accordance to IEC 750) and its service name. Other components located inside the switchboard, such as terminal blocks, transformers, relays, contactors, etc. are provided with item letter code number labels according to actual drawings.

1.2 General electrical characteristics

The switchboard structure is environmentally type-tested by authorized institutions SEARI in compliance with IEC 60439-1, IEC 60068 and IEC 60529 of following technical parameters: