Advantages of a video door intercom system with 2 wire BUS

For the wiring of a video door intercom system a so-called 2 wire system (DT system) is recommended. You can find out more about how it works in detail and what benefits are there for you. We also provide information about possible sources of error during installation.

A modern video door intercom system with 2 wire BUS from Schick-Handel realizes video, audio and the power supply via the so-called BUS and thus over two wires. To ensure a stable interfering signal, the cable cross-section should be between 0,8 and 1,5 millimeters. There is no polarity to consider - a great advantage, because the laying of the cables is thereby very simple.

An 2 wire door intercom can be easily extended

Route the two wires from the doorbell to the power distribution box (DPS powerwitch) from where the corresponding signals are sent to the video intercom points in the residential units. All devices of the respective intercom set can be encoded using the DIP code switch or via the master set-up menu so that they are recognized by the door intercom system. This allows your video door intercom with 2-wire BUS very easy to expand to up to 32 monitor video speakers and four doorbell call stations, which is another great advantage.

In addition, you can integrate intercom telephone modules (TPC) and cameras as well as image memory systems via DCU and network interfaces into your 2 wire door intercom system. If necessary, all householders will also receive a personal code card to open the front door. It is possible to allocate up to 1.000 cards in this way to a single doorknob station.

Door intercom system DM21

For the 2 wire bus, check the wire strength in the cable

During the installation of the video door intercom system with 2 wire BUS or even later, it may occasionally result in errors. If the instructions contained in the accompanying guide text are observed, however, these malfunctions can easily be avoided. The connection of an AC power supply (AC), for example, is not permissible because the system runs with direct current. Even if the wire strength in the cable used for the 2 wire bus is below 0,75 millimeters, the result is not very appealing, because the transmitted image is usually very poor or the screen only flickers. Here you will find an overview of these and other "malfunctions" of your intercom system, which will help you to find errors in the installation and to fix them without problems.