An intercom is a device designed to minimize the possibility of unauthorized entry into houses, apartments or other territory. Previously, this kind of equipment was called an intercom locking device (ROM), and this name is still sometimes found in receipts for payment of housing and communal services..
Today, such equipment is presented in a wide range by a large number of companies, so sometimes it is very difficult to choose one or another intercom model.
When choosing such a device, it should be borne in mind that any, even a time-tested IP intercom, must include a call unit, an apartment intercom, locks and keys. With the help of the call block, you can call the required apartment and communicate with it, and the intercom allows you to maintain communication between the visitor and the tenant. Locks block the front door, and keys allow residents to open the locks. In addition, intercoms can be equipped with a separate power supply, emergency battery, switch and electronics unit.
The choice of an intercom device should be based on the conditions of its operation and the requirements for it. Based on the features, such equipment is divided into simplex and duplex, digital and coordinate. Duplex doorphones allow communication in both directions (similar to a telephone). In this regard, in such equipment, handsets are usually used as apartment intercom devices..
Simplex systems allow communication in each direction in turn. With this technology, loudspeaker modules are used as apartment units. Currently mainly used duplex type systems.
As for the technological construction of such systems, digital intercoms are more reliable and easier to install and operate, since they provide for the use of a two-core cable. As the disadvantages of such devices, experts note the higher cost of the handset compared to coordinate-type intercoms, since it contains a decoder for the apartment call code.
Coordinate systems are more complex and material-intensive, but due to the cheapness of the tubes, they are in great demand..
