Main distribution boards (MDB)

Main distribution boards (GRShch) receive and distribute power (metering is also possible) in AC networks with separate earth and neutral (connection to networks with a solidly earthed neutral is also possible), and protect lines against overloads, leakage and short circuits. The most common are three-phase MDBs rated 0.4 kV with an earthed neutral. MDBs are installed in administrative, residential, retail and industrial buildings, transformer substations and other facilities to distribute power and protect both internal and external lines against short circuits and overloads.