Automatic Doorphones
Introduction
The video intercom (according to the Orthography of the RAE it is incorrect to write video intercom) is an autonomous system that serves to manage calls made at the door of a building (be it a residential complex, single-family home, work centers, etc.), controlling access to it through audiovisual communication between the interior and exterior through closed circuit television (CCTV).[1]
The main feature of the video intercom is that it allows the person occupying the interior to identify the visitor, being able, if they wish (and only if they wish), to start a conversation and/or open the door to allow access to the person who called.[2][3].
The team
The video intercom is made up of elements on the street and in the home: a panel on the outside, an electric door opener and a monitor for the interior.
The exterior panel or street panel is a panel that is installed next to the entrance door and in which different elements prepared for use in any climatic circumstance are integrated: one or more buttons to make the call inside (usually one per home), a microcamera adapted for night vision that captures the image of the person calling, a microphone that picks up their voice and a speaker that reproduces, on the street, the voice of the person occupying the interior.
The video intercom monitor, which is installed inside, consists of a screen on which the image of the person who called is displayed, a microphone and headset for conversation, and a button that allows the door release to be activated. The communication established is fully duplex, two-way.
The electric door opener is the device that is installed in the door lock so that, activated from inside the building, it lifts the latch, thus allowing the visitor to enter.
Common equipment variants
There are multiple variants on this basic format. In addition to the street panels with one button per home, it is possible to find others that have a numerical keypad: in this case, adapted for large residential groups, the homes are identified by codes. Others incorporate static information plates or even small screens to guide users or to facilitate use for people with disabilities.