Classic scheme of installation of door bell
Doorbells serve to signal the presence of a guest at the front door. In essence they are the most diverse – with mechanical bell melodic bells (e), wireless bells (e), etc. Here will be shown on a classical scheme such installation to which may be added and electron components. For example, to be replaced conventional electro-mechanical bells with electronic ones that have a variety of tunes.
Doorbells of an apartment consists of a bell placed in the entrance hall, two buttons – the front door of the apartment building (a boutonniere) and the front door of the apartment, connecting wires.
Power supply of doorbells for the entire building is performed by a general bell transformer. His classical performance is shown in Fig. 1. , the primary side is 220V/1A, the secondary side is with medium conclusion and accordingly 3V, 5V and 8V and power of 4VA. It is installed in the main switchboard at the entrance.
Wires are twisted pair of solid copper wire with insulation – PVU-A1-wire, insulation color blue and black. The temperature of the application it should not be less than -5 ° C. Section of the core is 0.5 – 0.75 mm ², the minimum bending radius is 10xD (for 0,5 mm ² D = 4,6 mm) the wires are as many as the number of apartments plus two. Both wires are common to all buttons respectively and all the bells. Installation of wires is hidden in the pipes through floors and junction boxes to buttons and bells for each apartment.
Bell wire is shown in Figure 2, and further details of its technical parameters can be found here.
Bells are varied and must be observed nominal secondary voltage (in case 8V), a power not exceeding 5VA as the ring volume is about 75dB. Usually it is installed above the front door in the hallway of the apartment. There are two buttons for each apartment – a button-down on the front door of the building and on the second floor near the door of the apartment. Their classic type in our country is shown in Fig. 3.
The circuit diagram of the coupling of three flats is shown in Fig. 4. And by following this principle can be made and the necessary number of units in each case.
In the next article will be shown how classical doorbells combined with one for intercom and unlock the electric lock.
