The presence of an intercom has long been an indispensable condition for ensuring the comfort of a modern apartment. The main purpose of these devices is to enable homeowners to receive calls from visitors and open doors remotely. Intercoms have proven to be much more convenient than outdated combination locks. Let's find out how to connect the handset of the apartment intercom on your own.
Types of modern intercoms
For reliable identification of visitors, an audio or video intercom is used. The latter is more often installed in private cottages and is designed for additional visual control of the space in front of the front door. As for urban apartments in high-rise buildings, they often install an audio option, the design of which includes the following elements:
- A handset that is equipped with buttons for accepting a call and opening an input electromagnetic or electromechanical lock. The device is installed by a company providing intercom installation and maintenance services. If such devices were not installed during the equipment of the entrance in some apartments, it is possible to install them yourself. You can also use the services of a specialist service company.
- Call panel equipped with a dial pad with numbers, which allows the visitor to signal the intercom handset by pressing the required code, usually the apartment number. In addition, there is a reader on the panel, with which you can use a special key to open an electromagnetic lock blocking the entrance doors.
- Locking device with power supply. The most common type of lock today is electromagnetic. Until recently, electromechanical latches equipped with sliding mechanisms were found everywhere. Such devices are often present in the entrances of apartment buildings even now. To operate the remote-controlled unit, you must use a constant voltage of 12 or 24 V.
- Switch. This device is designed to transmit a signal from the call panel to the subscriber handset of a particular apartment.
Depending on the type of signal processing, digital and analog intercoms are distinguished.
Important! Different types of receivers are used for digital and analog models. Before purchasing such a device, you should definitely find out what type is installed in the entrance.
Digital intercom
To connect devices of this type, only a cable with two cores is used, through which an encoded signal is transmitted. The handset installed in the apartment, the number of which was dialed on the call panel, responds to the given signal. To set the correspondence between the dialed code and the handset, special jumpers are used - jumpers - which bridge the necessary contacts in the response device.
To properly program the handset, jumpers are placed between the numbered terminals in such a way that the sum of the digits is equal to the apartment number.
The advantages of such intercoms include ease of installation and connection of new subscribers.
The main disadvantage of such equipment is the influence of each tube on the operation of the entire system. When replacing a device, which is carried out due to its breakdown, as well as when connecting new subscribers, the correct installation of jumpers is extremely important.
Attention! In the event of a digital tube connection error or a short circuit in the lead wires, the system may malfunction.
Currently, to partially eliminate this drawback, floor controllers are used, which allow localizing a malfunction within one level.
Another disadvantage of digital intercoms is their relative high cost, which does not allow these devices to be widely used.
Analog intercom
Analog installations use a coordinate matrix connection and work on the principle of a telephone exchange. An additional element of such a system is a switch, which processes and analyzes the signal, as well as redirects it to a specific subscriber.
Two buses are used to connect the intercom handset to the switch. Contacts of the first of them (D0–D9) correspond to tens, and the second (E0–E9) to units. Thus, in order to connect an intercom to an apartment, the number of which, for example, is 74, you need:
- connect the conductor from the positive terminal of the subscriber tube to the contact corresponding to the number 7 on the tens bus;
- the conductor adjacent to the negative terminal - to the contact corresponding to the number 4 on the unit bus.
In the considered connection option, a device designed to serve up to 100 subscribers was used. There are models that can work with a large number of numbers, but their principle of operation is no different from that discussed above.
If the numbers of the apartments located in the entrance do not allow connection, the installer reprograms the control panel with the numbers shifted by a certain number (for example, 84 must be subtracted from each). In this case, there is some difficulty in connecting, since without consulting a specialist who installed the intercom in the entrance, it is difficult to find out the amount of offset.
Connection order
The sequence of actions will be as follows:
- At the first stage of work, the location of the intercom handset is selected, then it is fixed on the wall using quick installation.
- Next, the installation location of the switch is determined (for analog intercoms). On each floor, they are installed in a junction box for low-current circuits. All of them are connected in parallel, which greatly simplifies the installation process. In the general case, only one switch per entrance is enough, however, when using such a scheme, it is necessary to stretch wires from the apartments of the upper floors to the installation site of the device.
- After removing the protective cover of the switch, the terminals corresponding to tens and ones are determined, then the connection is made, so that the sum of the numbers of these contacts shows the serial number of the apartment.
- Wires are connected to the tube. It is extremely important to respect the polarity. The positive terminal is connected to the contact of the switch corresponding to tens, the negative terminal - to units.
Important! If the polarity is not observed during the connection of the device of the coordinate-matrix system, the operation of the devices of the entire entrance may be disrupted.
Thus, the installation of an intercom handset is not particularly difficult. However, before you start doing such work with your own hands, it is important to determine the type and brand of the device used, as well as the location of the switch and the connection diagram of subscribers.
