Main switchboard (MSB) is an electrotechnical device that designed to supply, account and distribute electricity. Also, the main switchboard serves to protect against short circuits and overloads in networks with voltage up to 380 V AC, frequency 50 Hz. The main difference between the main switchboard from the switchgear (input distribution switchgear) is that the main switchboard is the first device in the switchboard equipment hierarchy after the step-down transformer 6-10 / 0.4 kV and therefore, most often, it is located on the territory of the transformer substation (TP 6-10 kV) and is part of it.
The main switchboard consists of panels that are divided according to their functional purpose into the following types:
– supply panels;
– line panels;
– sectional panels.
Depending on the tasks set by the Customer, the switchboard of the main switchboard can include in its structure an automatic transfer switch built, as a rule, on the basis of input and sectional automatic devices with motor drives.