Comparison Hikvision DS-KH6320-TE1 vs ARNY AVD-740

— Audio intercom. Intercoms with a wired connection, providing only voice communication between the guest and the host. They have low cost, but are not as convenient as video systems, since they do not allow you to see the visitor.

— Video intercom. Wired intercoms that allow the owner not only to hear, but also to see the guest. This provides additional convenience and security, however, such models are more expensive than audio intercoms (see above). In addition, not all outdoor panels provide the cameras necessary for video surveillance; and without cameras, the main advantage of such devices is completely lost.

— Radio intercom. Intercoms in which communication between the indoor unit and the calling panel is carried out via a radio channel. Such a connection is more expensive than a wired one, but it significantly simplifies the connection: you do not need to drill walls and pull wires. By specialization, models with a radio connection can refer to both audio and video intercoms; about those and others, see above.

— IP intercom. In intercoms of this type, the indoor unit and the calling panel are connected to a local computer network and exchange data through it. And some models are generally external calling panels that use a computer or other network device as an indoor unit. Anyway, one...of the key advantages of IP intercoms is the extensive possibilities for interacting with various devices, up to controlling curtains, lighting and other smart home components. In addition, such intercoms may even provide the ability to send notifications via the Internet — thus, the user will be able to receive information about visitors anywhere in the world where there is access to the Internet. The intercom itself can be connected to the network both by wire, via LAN, and via Wi-Fi (see "Additionally").

Type of connection with additional monitors (see "Number of monitors") supported by the intercom

— Consistent. With this type of connection, all external security devices — calling panels, cameras, locks, etc. — are connected only to the main intercom. Additional monitors used in the system are connected in a "chain", one after another, and work only through the main unit; you cannot connect security equipment directly to an additional monitor. With this format of operation, the number of security devices is limited by the capabilities of the main intercom, but they can be accessed from any system monitor.

— Parallel. Like serial, this option assumes the presence of a main intercom and additional monitors. The key difference lies in the fact that you can connect your own video cameras to each controlled monitor, which will be controlled only from this monitor. This option is convenient when organizing security systems with several separate video surveillance zones: for example, the main monitor can be installed at the main entrance, and the additional monitor at the service entrance, and each of them will only work with the camera above the corresponding door.

The total number of ports for wired connection of various equipment provided in the intercom; in fact — the maximum number of wired devices that can be simultaneously connected to the intercom.

Keep in mind that this number may be less than the total amount of supported devices. This is especially true in models with the possibility of using additional monitors (see "Connected monitors"): such devices are often connected in series, "chained" and occupy only 1 port. Thus, for example, an intercom for 2 calling panels and 3 monitors can have only 3 connectors — one for calling panels and one for monitors. Note also that the LAN port in IP intercoms (see "Device type") is also taken into account in this calculation.

The number of outdoor panels that can be connected to the intercom at the same time.

The call panel is an external panel through which the guest sends a call to the owner of the intercom and communicates with him. Such a panel should be at each door "covered" by the intercom. This means that the number of supported outdoor panels corresponds to the maximum number of doors with which this model can be used. The simplest option is 1 calling panel, but in fact this is often not enough. Therefore, models that can block 2 doors at once are more popular — for example, the main and service entrances to the office. And in the most advanced intercoms, it may be possible to connect 4 calling panels at once, or even more.

The number of additional monitors that can be connected to the intercom at the same time.

This function is relevant only for video-enabled models — video intercoms and IP intercoms (see “Device type”). In such models, the intercom itself is called a monitor — an indoor unit with a screen. This paragraph indicates how many additional indoor units can be connected to this model. The need for such a connection arises in cases where access to the security system must be provided from several points at once — for example, in a private house on several floors, where it would be inconvenient to run from floor to floor to the intercom. In this case, intercoms with access to 3 monitors, 4 monitors or more are appropriate.

Note that the format of multiple monitors working together may be different, see "Connection Type" for more details.

The number of video cameras that can be simultaneously connected to the intercom. The mode of operation with these cameras can be different — a mosaic of several signals at once, switching between signals with each one displayed on the full screen, etc. However, anyway, to work with several video cameras, it is desirable that their corresponding number be directly claimed in the intercom — otherwise you will have to resort to installing additional equipment.

The simplest modern intercoms allow the connection of 1 or 2 cameras, in more advanced ones this number can reach 4 or more.

The number of alarm inputs provided in the design of the intercom.

Such inputs allow the intercom to receive service signals from other elements of the security system — various sensors (motion, opening, temperature), cameras and video surveillance recorders, etc. This provides additional features for setting up the security system for certain events: for example, you can provide automatic activation of the video intercom camera when an opening sensor on an external wicket or gate is triggered. The specific functionality of alarm inputs for each model should be specified separately; however, anyway, such connectors allow you to increase automation and reduce dependence on the human factor. And the number of such inputs corresponds to the number of control components of the security system, which can be simultaneously connected to the intercom directly, without the use of additional equipment. Most often, it ranges from 3 to 8, and in some models it reaches one and a half dozen.

The number of alarm outputs provided for in the design of the intercom.

Alarm connectors are used to exchange service signals between individual components of the security system, most often to automatically turn on a particular function. The presence of alarm outputs in the intercom allows you to transmit control signals from it to other security devices — locks, spotlights, surveillance cameras, a siren, etc. For example, you can configure the system so that when you press the call button, not only the video intercom camera, but also external surveillance cameras.

The specific functionality of alarm outputs for each model should be specified separately; however, anyway, such connectors allow you to increase automation and reduce dependence on the human factor. And the number of such outputs corresponds to the number of controlled components of the security system, which can be simultaneously connected to the intercom directly, without the use of additional equipment. However, for a number of reasons, this number rarely exceeds 1.

The longest continuous conversation that the intercom provides. Technically, this duration can be unlimited, but in fact, limits can also be set — usually from 1 to 4 minutes. This is primarily due to the fact that in systems with several call panels, a conversation through one of them may interfere with the work of the others. Limitations on the duration allow you to exclude long conversations and possible overlays, and the available time is usually enough to clarify all the necessary questions during one conversation. Also, this feature is useful in case you forget to turn off the connection (hang up) at the end of the conversation.