The emDC* data concentrator is a device intended for data transmission from the mine underground to the surface. It is an underground telecommunication node enabling connection of multiple IT systems with such interfaces as: intrinsically safe serial transmission RS422 or RS485, intrinsically safe Ethernet. Data transmission is conducted via SHDSL modems. Additionally, it is possible to connect the emDC data concentrator to the underground fiberoptic network through the application of an intrinsically safe mediaconverter.