Communication equipment, which performs the function of distributing and amplifying the control bus signal to 4 outputs of the subcentral C2200, in the facilities that require it (up to 3 in cascade). The extension of the control bus is carried out by optical fiber, with two devices required for the connection (one as an emitter and the other as a receiver). It allows to extend the bus to another module D204F to a maximum of 2,000 m, by means of a pair of multimode fibers (850 Nm - 62.5 / 125) with ST connectors. The connection to fiber is indicated for reasons of distance and / or insulation against electrical disturbances of the bus. Each module can distribute the control bus in four copper branches, called Bus1 to Bus4 of 600 m each. 12V DC power supply (30 mA). Led indicators for diagnosis during start-up. Connection via plug-in strips (for 1.5 mm2 cable). Dimensions 101 x 105.5 x 24 mm, anchoring by DIN rail (35 mm symmetrical). Weight 133, 3 g. Temperature range -10 to 55ºC, relative humidity without condensation <93%.