This diagram shows a switchgear layout with two main busbars (B.B1 and B.B2), a main distribution board (MDB-1), two motorized vacuum circuit breakers (M.V.C1 and M.V.C2) connected to transformers (T1), and overcurrent relays (OCR-1 and OCR-2) protecting circuits connected to busbar B.B1 and the 1-3/C 150 kV circuit breaker.