The main switchboard MS is intended for reception, distribution and accounting of electric energy with voltage of 380/220 V three-phase AC with 50 HZ frequency in networks with dead-earthed neutral, for protection of lines at overloads and short circuits. The need for this switchboard arises in cases where the switchboard from the transformer substation needs to take a large power, while ensuring both the first category of reliability of power supply to the consumer, and the second category.
MS may consist of one or more shields. The purpose of the constituent parts of the main switchboard is divided into: introduction, distribution, breakout. The input elements are intended for entering electrical energy into the object. They can be used for electricity metering. The number of input panels in the MS varies from 1 to 3. Distribution panels are designed for connecting loads. They can be equipped with automatic switches of stationary type, plug-in and roll-out versions.
Features and benefits:
Products made on the basis of this metal structure are prefabricated, and therefore are easily assembled and disassembled into the parts necessary for transportation and installation on the site. Cabinets and other products are manufactured for both one-way and two-way maintenance. Cable or bus entries are provided in the panels in agreement with the customers. The input can be either top or bottom. The output can be carried out both through the panels in which the devices are installed, and through special panels, which is especially convenient for one-way maintenance. Shields are manufactured using high-precision equipment of imported production.
Usually, the MS is made with two input pull-out switches and one sectional switch, in three panels. The number of distribution panels is determined by the cross section and number of outgoing cables, the type and size of circuit breakers.
The dimensions of the input panels of the MS and the design features of the switch bushing allow the use of double and split cables to increase the cross-section of the supply cable lines. Recommended input of power cables to the MS from the bottom, as well as power to the MS from transformers can be organized using busbars, while the input of power busbars is recommended from the top.