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DOUBLE BUSBAR SWITCHGEAR FOR LARGE ELECTRICAL PLANTS

In the study and design phases of electrical switchgears it is fundamental to consider the circumstances related to their destination and application, in order to guarantee a greater safety and efficiency of the system.

Among the switchgears for special applications carried out by C.R. Technology Systems, the Normal Clad with Double Busbar system with power up to 36kV has unique features. It is used when the request to continuity of service, such as in large substations, in electrical service companies or in heavy industries.

In addition, it ensures access to one of the two busbar systems during maintenance operations, keeping the other active, thanks to the possibility of isolating one or more outgoing cubicles. It is also possible to extend the switchgear configuration on both ends without putting out of service the switchgear itself.

CONFIGURATION

The Normal Clad switchgear with double busbar system consists of two main units:

  • Cubicle
  • Protection, monitoring and control systems

Cubicle

Normal Clad cubicles with double busbar system are LSC2B (Loss of Service Continuity Category), in accordance with the IEC 62271-200 standard, in which the medium voltage compartments are metallically segregated (PM class), and they are divided into:

  • Double busbar system
  • N. 2 rotary disconnectors and an earthing switch
  • Circuit-breaker
  • Withdrawable VT (on request)
  • Fixed AT
  • Surge and capacitive arresters

The busbar and line compartments are accessible from the rear of the switchboard by means of removable panels. All standard operations are performed from the front, while maintenance and commissioning operations require access from both sides (front and back).

Protection, monitoring and control system

This unit includes:

  • Low-voltage section
  • Protection, monitoring and control section
  • Internal-arc protection system
  • Current transformers
  • Voltage transformers

High standard of performances

The double busbar system guarantees the following performances:

  • Continuity of service
  • Easy extension of the plant
  • Flexible and reduced maintenance operations
  • Greater safety for operators
  • Ease of carrying out load shedding, or load disconnection, carried out when there is a reduction in power available from the incoming cubicle, resulting in insufficient power to supply the whole switchgear; therefore, the non-priority units are isolated and are not powered
  • Sectioning of particular starting units from the grid
  • Motorized busbar disconnector that allows rapid switching between the two busbar systems in emergency conditions (only possible with the cross busbar closed)