The Prisma TT functional system can be used for all types of low-voltage distribution switchboards and motor control centers up to 4000A, in buildings and industrial environments. The switchboard is made up of a single framework combined side-by-side, on which complete selection of cover panels and doors can be mounted. Horizontal busbars or vertical busbars positioned in a lateral compartment or at the rear of the cubicle are used to distribute electricity throughout the switchboard. Each device is part of a functional unit comprising of a dedicated mounting plate for device installation, a partial door and Busbar connections. Each functional unit contributes to a function in the switchboard. The functional units are modular and are arranged rationally, one on top of another, within the enclosure. The system includes everything required for functional unit mounting, supply and on-site connection. The components of the Prisma TT system and those of the functional units in particular have been designed and tested taking into account device characteristics. This design approach ensures a high degree of reliability in system operation and optimum safety of personnel.