Built-in door intercom for installation in mailbox systems (RENZ, type RSA2) with interface for 8 call buttons for connection to the VT200 system. Reverse polarity protected 2-wire bus connection to a VT200 system power supply. Connection for analog camera (BNC coupling, PAL signal). 8 cable connections for call buttons (normally open contacts, NO). Connection for door opener (ET100A or 12V DC, max. 250mA via bus supply or via integrated potential-free relay (24V AC/DC, max. 1A). Door opening time: adjustable 1-99 sec. Without RFID reading function. Power supply: 24-29V DC, max. 3W from system power supply unit. Max. 4 door intercoms can be operated in the system. By connecting call button extensions VT200RE, up to a total of 32 call buttons can be operated in the system. Dimensions: 100 x 84 x 40mm (door intercom), 47 x 47 x 17mm (interface). Suitable accessories: call button extension for 8 call buttons VT200RE.