Abstract: An energy supply train for under-ground mining has several universal transport unit frames (UTU frames) (1) inter-connected by drawbars and useful as elements of a suspended monorail. At least one of the U68TU frames carries a heavy-duty transformer and at least another UTU frame carries a compact station (4, 5) arranged in a pressure-resistant housing (2, 3) with switchgear (13, 14, 15, 16) for supplying electric energy to underground working means and with electric connection devices (10, 11) at the input and output side of the pressure-resistant housing (2, 3). Each UTU frame (1) carries two compact stations (4, 5) mechanically interconnected by a box (6) and electrically interconnected by electric lines (17) that extend through said box (6) so as to form a single device. The electric connection devices are verified by means of authorised power outlets directly arranged on the walls of the pressure-resistant housings (2, 3) of the compact stations (4, 5).