2VOICE, two wires throughout the system for quick and easy installation. Maximum flexibility: from single-family homes to larger building complexes.Product features:Riser interfacefor max. 128 devices in one riser (with VV 1083/55) max. 4 risers can be connected for top hat rail mountingTechnical data:Compatible with System 2VOICESupply voltage: 36 - 48V DC (via bus) Width: 10 sub-units (180mm) Installation instructions:Note: